id
stringlengths 9
16
| submitter
stringlengths 1
64
⌀ | authors
stringlengths 3
62.8k
| title
stringlengths 1
382
| comments
stringlengths 1
1.15k
⌀ | journal-ref
stringlengths 1
557
⌀ | doi
stringlengths 7
153
⌀ | report-no
stringlengths 1
509
⌀ | categories
stringlengths 5
125
| license
stringclasses 9
values | abstract
stringlengths 6
6.09k
| versions
listlengths 1
187
| update_date
timestamp[s]date 2007-05-23 00:00:00
2025-04-04 00:00:00
| authors_parsed
sequencelengths 1
2.83k
|
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
quant-ph/9609010 | Vladimir Privman | Dima Mozyrsky, Vladimir Privman | Quantum signal splitting that avoids initialization of the targets | 16 pages in plain TeX and one Postscript figure | Mod.Phys.Lett.B11:1277-1283,1997 | 10.1142/S0217984997001523 | null | quant-ph cond-mat | null | The classical signal splitting and copying are not possible in quantum
mechanics. Specifically, one cannot copy the basis up and down states of the
input (I) two-state system (qubit, spin) into the copy (C) and duplicate-copy
(D) two-state systems if the latter systems are initially in an arbitrary
state. We consider instead a quantum evolution in which the basis states of I
at time t are duplicated in at least two of the systems I, C, D, at time t +
Delta t. In essence, the restriction on the initial target states is exchanged
for uncertainty as to which two of the three qubits retain copies of the
initial source state.
| [
{
"version": "v1",
"created": "Mon, 16 Sep 1996 16:55:52 GMT"
},
{
"version": "v2",
"created": "Sun, 31 Aug 1997 15:01:27 GMT"
}
] | 2014-11-18T00:00:00 | [
[
"Mozyrsky",
"Dima",
""
],
[
"Privman",
"Vladimir",
""
]
] |
quant-ph/9609011 | Andreas Fring | C. Figueira de Morisson Faria, A. Fring and R. Schrader | On the Influence of Pulse Shapes on Ionization Probability | 21 pages LateX, 10 figures | J.Phys. B31 (1998) 449 | 10.1088/0953-4075/31/3/013 | SfB-288 Preprint No.224, Berlin | quant-ph atom-ph chem-ph | null | We investigate analytical expressions for the upper and lower bounds for the
ionization probability through ultra-intense shortly pulsed laser radiation. We
take several different pulse shapes into account, including in particular those
with a smooth adiabatic turn-on and turn-off. For all situations for which our
bounds are applicable we do not find any evidence for bound-state
stabilization.
| [
{
"version": "v1",
"created": "Mon, 16 Sep 1996 17:26:44 GMT"
},
{
"version": "v2",
"created": "Thu, 10 Apr 1997 15:25:01 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Faria",
"C. Figueira de Morisson",
""
],
[
"Fring",
"A.",
""
],
[
"Schrader",
"R.",
""
]
] |
quant-ph/9609012 | Zdenek Hradil | Zdenek Hradil, (Department of Optics, Olomouc) | Quantum state estimation | 4 pages, twocolumn Revtex | null | 10.1103/PhysRevA.55.R1561 | null | quant-ph | null | New algorithm for quantum state estimation based on the maximum likelihood
estimation is proposed. Existing techniques for state reconstruction based on
the inversion of measured data are shown to be overestimated since they do not
guarantee the positive definiteness of the reconstructed density matrix.
| [
{
"version": "v1",
"created": "Tue, 17 Sep 1996 10:07:00 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Hradil",
"Zdenek",
""
]
] |
quant-ph/9609013 | N. David Mermin | N. David Mermin | The Ithaca Interpretation of Quantum Mechanics | 21 pages, plain TEX. Notes for a lecture given at the Golden Jubilee
Workshop on Foundations of Quantum Theory, Tata Institute, Bombay, September
9-12, 1996 | Pramana 51:549-565,1998 | 10.1007/BF02827447 | null | quant-ph | null | I list several strong requirements for what I would consider a sensible
interpretation of quantum mechanics and I discuss two simple theorems. One, as
far as I know, is new; the other was only noted a few years ago. Both have
important implications for such a sensible interpretation. My talk will not
clear everything up; indeed, you may conclude that it has not cleared anything
up. But I hope it will provide a different perspective from which to view some
old and vexing puzzles (or, if you believe nothing needs to be cleared up, some
ancient verities.)
| [
{
"version": "v1",
"created": "Tue, 17 Sep 1996 17:43:34 GMT"
}
] | 2011-04-11T00:00:00 | [
[
"Mermin",
"N. David",
""
]
] |
quant-ph/9609014 | null | Giuseppe Vitiello (Dipartimento di Fisica, Universita' di Salerno,
Italia) | Structure and Function | to appear in Proceed. of the Tucson 1996 Conference "Towards a
Science of Consciousness" Latex file | null | null | null | quant-ph | null | I discuss the role of quantum dynamics in brain and living matter physics.
The paper is presented in the form of a letter to Patricia S. Churchland.
| [
{
"version": "v1",
"created": "Wed, 18 Sep 1996 17:57:14 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Vitiello",
"Giuseppe",
"",
"Dipartimento di Fisica, Universita' di Salerno,\n Italia"
]
] |
quant-ph/9609015 | Asher Peres | Asher Peres | Unitary dynamics for quantum codewords | 10 pages LaTeX, to appear in proceedings of symposium on quantum
communication and measurement (Plenum) | "Quantum Communication, Computing and Measurement" ed. by O.
Hirota, A.S. Holevo, and C.M. Caves (Plenum, 1997) pp.171-179 | null | null | quant-ph | null | A quantum codeword is a redundant representation of a logical qubit by means
of several physical qubits. It is constructed in such a way that if one of the
physical qubits is perturbed, for example if it gets entangled with an unknown
environment, there still is enough information encoded in the other physical
qubits to restore the logical qubit, and disentangle it from the environment.
The recovery procedure may consist of the detection of an error syndrome,
followed by the correction of the error, as in the classical case. However, it
can also be performed by means of unitary operations, without having to know
the error syndrome. Since quantum codewords span only a restricted subspace of
the complete physical Hilbert space, the unitary operations that generate
quantum dynamics (that is, the computational process) are subject to
considerable arbitrariness, similar to the gauge freedom in quantum field
theory. Quantum codewords can thus serve as a toy model for investigating the
quantization of constrained dynamical systems.
| [
{
"version": "v1",
"created": "Wed, 18 Sep 1996 23:59:57 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Peres",
"Asher",
""
]
] |
quant-ph/9609016 | Asher Peres | Asher Peres | Quantum nonlocality and inseparability | 14 pages LaTeX, to appear in proceedings of symposium on fundamental
problems in quantum physics, Oviedo 1996 (Kluwer Academic Publishers). One
figure may be requested from the author | "New Developments on Fundamental Problems in Quantum Physics" ed.
by M. Ferrero and A. van der Merwe (Kluwer, 1997) pp.301-310 | null | null | quant-ph | null | A quantum system consisting of two subsystems is separable if its density
matrix can be written as $\rho=\sum w_K \rho_K'\otimes \rho_K''$, where
$\rho_K'$ and $\rho_K''$ are density matrices for the two subsytems, and the
positive weights $w_K$ satisfy $\sum w_K=1$. A necessary condition for
separability is derived and is shown to be more sensitive than Bell's
inequality for detecting quantum inseparability. Moreover, collective tests of
Bell's inequality (namely, tests that involve several composite systems
simultaneously) may sometimes lead to a violation of Bell's inequality, even if
the latter is satisfied when each composite system is tested separately.
| [
{
"version": "v1",
"created": "Thu, 19 Sep 1996 00:36:45 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Peres",
"Asher",
""
]
] |
quant-ph/9609017 | null | D.A. Trifonov | Schr\"{o}dinger Intelligent States and Linear and Quadratic Amplitude
Squeezing | 33 pages, latex, 4 figures available upon request. In the replaced
version 2 references (the last ones) are added | null | null | Preprint INRNE-TH-96/6 | quant-ph | null | A complete set of solutions |z,u,v>_{sa} of the eigenvalue equation
(ua^2+va^{dagger 2})|z,u,v> = z|z,u,v> ([a,a^{dagger}]=1) are constructed and
discussed. These and only these states minimize the Schr\"{o}dinger uncertainty
inequality for the squared amplitude (s.a.) quadratures. Some general
properties of Schr\"{o}dinger intelligent states (SIS) |z,u,v> for any two
observables X, Y are discussed, the sets of even and odd s.a. SIS |z,u,v;+,->
being studied in greater detail. The set of s.a. SIS contain all even and odd
coherent states (CS) of Dodonov, Malkin and Man'ko, the Perelomov SU(1,1) CS
and the squeezed Hermite polynomial states of Bergou, Hillery and Yu. The even
and odd SIS can exhibit very strong both linear and quadratic squeezing (even
simultaneously) and super- and subpoissonian statistics as well. A simple
sufficient condition for superpoissonian statistics is obtained and the
diagonalization of the amplitude and s.a. uncertainty matrices in any pure or
mixed state by linear canonical transformations is proven.
| [
{
"version": "v1",
"created": "Thu, 19 Sep 1996 16:45:31 GMT"
},
{
"version": "v2",
"created": "Mon, 23 Sep 1996 15:02:49 GMT"
}
] | 2008-02-03T00:00:00 | [
[
"Trifonov",
"D. A.",
""
]
] |
quant-ph/9609018 | Vladimir Privman | Dima Mozyrsky, Vladimir Privman, Mark Hillery | A Hamiltonian for quantum copying | 16 pages in plain TeX | Phys.Lett.A226:253-256,1997 | 10.1016/S0375-9601(96)00939-5 | null | quant-ph cond-mat.mtrl-sci | null | We derive an explicit Hamiltonian for copying the basis up and down states of
a quantum two-state system - a qubit - onto n "copy" qubits initially all
prepared in the down state. In terms of spin components, for spin-1/2 particle
spin states, the resulting Hamiltonian involves n- and (n+1)-spin interactions.
The case n=1 also corresponds to a quantum-computing controlled-NOT gate.
| [
{
"version": "v1",
"created": "Tue, 24 Sep 1996 22:00:00 GMT"
},
{
"version": "v2",
"created": "Sat, 10 May 1997 12:19:10 GMT"
}
] | 2014-11-18T00:00:00 | [
[
"Mozyrsky",
"Dima",
""
],
[
"Privman",
"Vladimir",
""
],
[
"Hillery",
"Mark",
""
]
] |
quant-ph/9609019 | null | Andrew J. Bordner | Operator Transformations Between Exactly Solvable Potentials and Their
Lie Group Generators | 13 pages with one Postscript figure, uses LaTeX2e with revtex | J.Phys.A30:3927,1997 | 10.1088/0305-4470/30/11/020 | KUNS-1410, HE(TH) 96/11 | quant-ph | null | One may obtain, using operator transformations, algebraic relations between
the Fourier transforms of the causal propagators of different exactly solvable
potentials. These relations are derived for the shape invariant potentials.
Also, potentials related by real transformation functions are shown to have the
same spectrum generating algebra with Hermitian generators related by this
operator transformation.
| [
{
"version": "v1",
"created": "Thu, 26 Sep 1996 13:25:35 GMT"
},
{
"version": "v2",
"created": "Fri, 27 Sep 1996 06:09:28 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Bordner",
"Andrew J.",
""
]
] |
quant-ph/9609020 | Alan Kostelecky | Robert Bluhm, Alan Kostelecky, and Bogdan Tudose | Wave-Packet Revivals for Quantum Systems with Nondegenerate Energies | accepted for publication in Physics Letters A | Phys.Lett.A222:220,1996 | 10.1016/0375-9601(96)00641-X | IUHET 338, July 1996 | quant-ph | null | The revival structure of wave packets is examined for quantum systems having
energies that depend on two nondegenerate quantum numbers. For such systems,
the evolution of the wave packet is controlled by two classical periods and
three revival times. These wave packets exhibit quantum beats in the initial
motion as well as new types of long-term revivals. The issue of whether
fractional revivals can form is addressed. We present an analytical proof
showing that at certain times equal to rational fractions of the revival times
the wave packet can reform as a sum of subsidiary waves and that both
conventional and new types of fractional revivals can occur.
| [
{
"version": "v1",
"created": "Thu, 26 Sep 1996 17:35:58 GMT"
}
] | 2009-09-25T00:00:00 | [
[
"Bluhm",
"Robert",
""
],
[
"Kostelecky",
"Alan",
""
],
[
"Tudose",
"Bogdan",
""
]
] |
quant-ph/9609021 | Mark J. Hadley | Mark J. Hadley | A Gravitational Explanation for Quantum Mechanics | 10 pages Latex2e, talk given at the 5th UK Conference on Conceptual
and Philosophical Problems in Physics held in Oxford, 10th-14th September
1996 | null | null | null | quant-ph gr-qc | null | It is shown that certain structures in classical General Relativity can give
rise to non-classical logic, normally associated with Quantum Mechanics. A
4-geon model of an elementary particle is proposed which is asymptotically
flat, particle-like and has a non-trivial causal structure. The usual Cauchy
data are no longer sufficient to determine a unique evolution. The measurement
apparatus itself can impose non-redundant boundary conditions. Measurements of
such an object would fail to satisfy the distributive law of classical physics.
This model reconciles General Relativity and Quantum Mechanics without the need
for Quantum Gravity. The equations of Quantum Mechanics are unmodified but it
is not universal; classical particles and waves could exist and there is no
graviton.
| [
{
"version": "v1",
"created": "Fri, 27 Sep 1996 12:19:18 GMT"
}
] | 2024-01-03T00:00:00 | [
[
"Hadley",
"Mark J.",
""
]
] |
quant-ph/9609022 | M. Czachor | Marek Czachor | Einstein-Podolsky-Rosen-Bohm experiment with relativistic massive
particles | Figures added as appeared in PRA, two typos corrected (one important
in the formula for eigenvector in Sec. IV); link to the unpublished 1984
paper containing the results (without typos!) of Sec. IV is added | Phys.Rev. A55 (1997) 72 | 10.1103/PhysRevA.55.72 | null | quant-ph | null | The EPRB experiment with massive partcles can be formulated if one defines
spin in a relativistic way. Two versions are discussed: The one using the spin
operator defined via the relativistic center-of-mass operator, and the one
using the Pauli-Lubanski vector. Both are shown to lead to the SAME prediction
for the EPRB experiment: The degree of violation of the Bell inequality
DECREASES with growing velocity of the EPR pair of spin-1/2 particles. The
phenomenon can be physically understood as a combined effect of the Lorentz
contraction and the Moller shift of the relativistic center of mass. The effect
is therefore stronger than standard relativistic phenomena such as the Lorentz
contraction or time dilatation. The fact that the Bell inequality is in general
less violated than in the nonrelativistic case will have to be taken into
account in tests for eavesdropping if massive particles will be used for a key
transfer.
| [
{
"version": "v1",
"created": "Fri, 27 Sep 1996 13:40:53 GMT"
},
{
"version": "v2",
"created": "Sat, 1 Nov 2003 18:09:21 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Czachor",
"Marek",
""
]
] |
quant-ph/9609023 | Olavo Leopoldino Da Silva Filho | L.S.F. Olavo | Quantum Mechanics as a Classical Theory XIV: Connection with Stochastic
Processes | plain latex, no figures, 15 pages | null | null | unb-014 | quant-ph | null | In this paper we are interested in unraveling the mathematical connections
between the stochastic derivation of Schr\"odinger equation and ours. It will
be shown that these connections are given by means of the time-energy
dispersion relation and will allow us to interpret this relation on more
sounded grounds. We also discuss the underlying epistemology.
| [
{
"version": "v1",
"created": "Fri, 27 Sep 1996 18:23:19 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Olavo",
"L. S. F.",
""
]
] |
quant-ph/9609024 | Chris Adami | C. Adami and N.J. Cerf (California Institute of Technology) | On the von Neumann capacity of noisy quantum channels | 15 pages RevTeX with psfig, 13 figures. Revised interpretation of
capacity, added section, changed title | Phys.Rev.A56:3470,1997 | 10.1103/PhysRevA.56.3470 | KRL MAP-206 | quant-ph | null | We discuss the capacity of quantum channels for information transmission and
storage. Quantum channels have dual uses: they can be used to transmit known
quantum states which code for classical information, and they can be used in a
purely quantum manner, for transmitting or storing quantum entanglement. We
propose here a definition of the von Neumann capacity of quantum channels,
which is a quantum mechanical extension of the Shannon capacity and reverts to
it in the classical limit. As such, the von Neumann capacity assumes the role
of a classical or quantum capacity depending on the usage of the channel. In
analogy to the classical construction, this capacity is defined as the maximum
von Neumann mutual entropy processed by the channel, a measure which reduces to
the capacity for classical information transmission through quantum channels
(the "Kholevo capacity") when known quantum states are sent. The quantum mutual
entropy fulfills all basic requirements for a measure of information, and
observes quantum data-processing inequalities. We also derive a quantum Fano
inequality relating the quantum loss of the channel to the fidelity of the
quantum code. The quantities introduced are calculated explicitly for the
quantum "depolarizing" channel. The von Neumann capacity is interpreted within
the context of superdense coding, and an "extended" Hamming bound is derived
that is consistent with that capacity.
| [
{
"version": "v1",
"created": "Fri, 27 Sep 1996 23:17:08 GMT"
},
{
"version": "v2",
"created": "Wed, 23 Oct 1996 02:27:50 GMT"
},
{
"version": "v3",
"created": "Tue, 3 Jun 1997 02:35:23 GMT"
}
] | 2008-12-18T00:00:00 | [
[
"Adami",
"C.",
"",
"California Institute of Technology"
],
[
"Cerf",
"N. J.",
"",
"California Institute of Technology"
]
] |
quant-ph/9609025 | Mark J. Gotay | Mark J. Gotay, Hendrik B. Grundling | On Quantizing $T^*S^1$ | LaTeX, 19 pps | Rept.Math.Phys. 40 (1997) 107-123 | 10.1016/S0034-4877(97)85622-4 | null | quant-ph dg-ga hep-th math.DG | null | In this paper we continue our study of Groenewold-Van Hove obstructions to
quantization. We show that there exists such an obstruction to quantizing the
cylinder $T^*S^1.$ More precisely, we prove that there is no quantization of
the Poisson algebra of $T^*S^1$ which is irreducible on a naturally defined
$e(2) \times R$ subalgebra. Furthermore, we determine the maximal
``polynomial'' subalgebras that can be consistently quantized, and completely
characterize the quantizations thereof. This example provides support for one
of the conjectures in Gotay et al 1996, but disproves part of another. Passing
to coverings, we also derive a no-go result for $R^2$ which is comparatively
stronger than those originally found by Groenewold and Van Hove.
| [
{
"version": "v1",
"created": "Sat, 28 Sep 1996 00:15:28 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Gotay",
"Mark J.",
""
],
[
"Grundling",
"Hendrik B.",
""
]
] |
quant-ph/9609026 | null | Stefano Mancini, Vladimir I. Man'ko, and Paolo Tombesi | Classical-Like Description of Quantum Dynamics by Means of Symplectic
Tomography | 29 pages,LATEX,accepted by Foundations of Physics | Found.Phys. 27 (1997) 801 | 10.1007/BF02550342 | null | quant-ph | null | The dynamical equation of quantum mechanics are rewritten in form of
dynamical equations for the measurable, positive marginal distribution of the
shifted, rotated and squeezed quadrature introduced in the so called
"symplectic tomography". Then the possibility of a purely classical description
of a quantum system as well as a reinterpretation of the quantum measurement
theory is discussed and a comparision with the well known quasi-probabilities
approach is given. Furthermore, an analysis of the properties of this marginal
distribution, which contains all the quantum information, is performed in the
framework of classical probability theory. Finally examples of harmonic
oscillator's states dynamics are treated.
| [
{
"version": "v1",
"created": "Sat, 28 Sep 1996 11:17:00 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Mancini",
"Stefano",
""
],
[
"Man'ko",
"Vladimir I.",
""
],
[
"Tombesi",
"Paolo",
""
]
] |
quant-ph/9609027 | Wolfhard Janke | Wolfhard Janke, Hagen Kleinert (JGU Mainz, FU Berlin) | Convergence Behavior of Variational Perturbation Expansions | 5 pages, LaTeX + 2 postscript figures. Talk presented by WJ at "Path
Integrals from meV to MeV: Dubna '96". See also
http://www.cond-mat.physik.uni-mainz.de/~janke/doc/home_janke.html | null | null | KOMA-96-35 | quant-ph | null | Variational weak-coupling perturbation theory yields converging
approximations, uniformly in the coupling strength. This allows us to calculate
directly the coefficients of `strong-coupling' expansions. For the anharmonic
oscillator we explain the physical origin of the empirically observed
convergence behavior which is exponentially fast with superimposed
oscillations.
| [
{
"version": "v1",
"created": "Sat, 28 Sep 1996 22:57:51 GMT"
}
] | 2016-09-08T00:00:00 | [
[
"Janke",
"Wolfhard",
"",
"JGU Mainz, FU Berlin"
],
[
"Kleinert",
"Hagen",
"",
"JGU Mainz, FU Berlin"
]
] |
quant-ph/9610001 | Michael Nielsen | Isaac L. Chuang and M. A. Nielsen | Prescription for experimental determination of the dynamics of a quantum
black box | 6 pages, Revtex. Submitted to J. Mod. Opt | null | 10.1080/09500349708231894 | null | quant-ph | null | We give an explicit prescription for experimentally determining the evolution
operators which completely describe the dynamics of a quantum mechanical black
box -- an arbitrary open quantum system. We show necessary and sufficient
conditions for this to be possible, and illustrate the general theory by
considering specifically one and two quantum bit systems. These procedures may
be useful in the comparative evaluation of experimental quantum measurement,
communication, and computation systems.
| [
{
"version": "v1",
"created": "Tue, 1 Oct 1996 16:21:11 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Chuang",
"Isaac L.",
""
],
[
"Nielsen",
"M. A.",
""
]
] |
quant-ph/9610002 | Funahashi Kunio | Kazuyuki Fujii and Kunio Funahashi | Multi-Periodic Coherent States and the WKB-Exactness II ``Non-compact
Case and Classical theories Revisited'' | LaTeX, 29 pages | J.Math.Phys. 38 (1997) 2812-2831 | 10.1063/1.532021 | null | quant-ph | null | We show that the WKB approximation gives the exact result in the trace
formula of ``$CQ^N$'', which is the non-compact counterpart of $CP^N$, in terms
of the ``multi-periodic'' coherent state. We revisit the symplectic 2-forms on
$CP^N$ and $CQ^N$ and, especially, construct that on $CQ^N$ with the unitary
form. We also revisit the exact calculation of the classical patition functions
of them.
| [
{
"version": "v1",
"created": "Wed, 2 Oct 1996 04:20:42 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Fujii",
"Kazuyuki",
""
],
[
"Funahashi",
"Kunio",
""
]
] |
quant-ph/9610003 | Dirk Sondermann | Almut Beige, Gerhard C. Hegerfeldt, Dirk G. Sondermann | Atomic Quantum Zeno Effect for Ensembles and Single Systems | 19 pages, LaTeX, a4.sty | Found.Phys.27:1671-1688,1997 | 10.1007/BF02551444 | null | quant-ph | null | The so-called quantum Zeno effect is essentially a consequence of the
projection postulate for ideal measurements. To test the effect Itano et al.
have performed an experiment on an ensemble of atoms where rapidly repeated
level measurements were realized by means of short laser pulses. Using
dynamical considerations we give an explanation why the projection postulate
can be applied in good approximation to such measurements. Corrections to ideal
measurements are determined explicitly. This is used to discuss in how far the
experiment of Itano et al. can be considered as a test of the quantum Zeno
effect. We also analyze a new possible experiment on a single atom where
stochastic light and dark periods can be interpreted as manifestation of the
quantum Zeno effect. We show that the measurement point of view gives a quick
and intuitive understanding of experiments of the above type, although a finer
analysis has to take the corrections into account.
| [
{
"version": "v1",
"created": "Wed, 2 Oct 1996 10:55:47 GMT"
}
] | 2014-11-18T00:00:00 | [
[
"Beige",
"Almut",
""
],
[
"Hegerfeldt",
"Gerhard C.",
""
],
[
"Sondermann",
"Dirk G.",
""
]
] |
quant-ph/9610004 | Marc Jaekel | Marc-Thierry Jaekel (Laboratoire de Physique Th\'eorique de l'Ecole
Normale Sup\'erieure) and Serge Reynaud (Laboratoire Kastler-Brossel) | Mass as a Relativistic Quantum Observable | 5 pages, revised version | Europhys.Lett.38:1,1977 | 10.1209/epl/i1997-00108-7 | LPTENS 96/53 | quant-ph gr-qc | null | A field state containing photons propagating in different directions has a
non vanishing mass which is a quantum observable. We interpret the shift of
this mass under transformations to accelerated frames as defining space-time
observables canonically conjugated to energy-momentum observables. Shifts of
quantum observables differ from the predictions of classical relativity theory
in the presence of a non vanishing spin. In particular, quantum redshift of
energy-momentum is affected by spin. Shifts of position and energy-momentum
observables however obey simple universal rules derived from invariance of
canonical commutators.
| [
{
"version": "v1",
"created": "Thu, 3 Oct 1996 10:46:45 GMT"
},
{
"version": "v2",
"created": "Mon, 16 Jun 1997 10:03:12 GMT"
}
] | 2010-12-17T00:00:00 | [
[
"Jaekel",
"Marc-Thierry",
"",
"Laboratoire de Physique Théorique de l'Ecole\n Normale Supérieure"
],
[
"Reynaud",
"Serge",
"",
"Laboratoire Kastler-Brossel"
]
] |
quant-ph/9610005 | Nicolas Cerf | Nicolas J. Cerf, Chris Adami (California Institute of Technology) | Negative entropy in quantum information theory | 8 pages LaTeX, 2 figures, to appear in the Proceedings of the 2nd
International Symposium on Fundamental Problems in Quantum Physics, Oviedo 96
(Kluwer Academic Publishers) | null | null | null | quant-ph | null | We present a quantum information theory that allows for the consistent
description of quantum entanglement. It parallels classical (Shannon)
information theory but is based entirely on density matrices, rather than
probability distributions, for the description of quantum ensembles. We find
that, unlike in Shannon theory, conditional entropies can be negative when
considering quantum entangled systems such as an Einstein-Podolsky-Rosen pair,
which leads to a violation of well-known bounds of classical information
theory. Negative quantum entropy can be traced back to ``conditional'' density
matrices which admit eigenvalues larger than unity. A straightforward
definition of mutual quantum entropy, or ``mutual entanglement'', can also be
constructed using a ``mutual'' density matrix. Such a unified
information-theoretic description of classical correlation and quantum
entanglement clarifies the link between them: the latter can be viewed as
``super-correlation'' which can induce classical correlation when considering a
ternary or larger system.
| [
{
"version": "v1",
"created": "Thu, 3 Oct 1996 17:52:33 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Cerf",
"Nicolas J.",
"",
"California Institute of Technology"
],
[
"Adami",
"Chris",
"",
"California Institute of Technology"
]
] |
quant-ph/9610006 | Henrik Carlsen | Erik Sjoeqvist, Henrik Carlsen and Harvey R. Brown | Galilean non-invariance of geometric phase | LaTeX, 6 pages, no figures | null | 10.1016/S0375-9601(97)00214-4 | null | quant-ph | null | It is shown that geometric phase in non-relativistic quantum mechanics is not
Galilean invariant.
| [
{
"version": "v1",
"created": "Sun, 6 Oct 1996 18:59:25 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Sjoeqvist",
"Erik",
""
],
[
"Carlsen",
"Henrik",
""
],
[
"Brown",
"Harvey R.",
""
]
] |
quant-ph/9610007 | Ken Umeno | Ken Umeno | Integrability and Computability in Simulating Quantum Systems | 9 pages, Latex, Related papers are on
http://www.bip.riken.go.jp/irl/chaosken/quantum.html | in "Quantum Communication, Computing, and Measurement", Edited by
O. Hirota, A.S.Holevo and C.M. Caves, p.p.195-201(Plenum Press, 1997). | null | null | quant-ph | null | An impossibility theorem on approximately simulating quantum non-integrable
Hamiltonian systems is presented here. This result shows that there is a
trade-off between the unitary property and the energy expectation conservation
law in time-descretization of quantum non-integrable systems, whose classical
counterpart is Ge-Marsden's impossibility result about simulating classically
non-integrable Hamiltonian systems using integration schemes preserving
symplectic (Lie-Poisson) property.
| [
{
"version": "v1",
"created": "Fri, 4 Oct 1996 22:33:40 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Umeno",
"Ken",
""
]
] |
quant-ph/9610008 | Vladimir Privman | Dima Mozyrsky, Vladimir Privman, Steven P. Hotaling | Extended Quantum XOR Gate in Terms of Two-Spin Interactions | 15 pages in plain TeX with 1 Postscript figure | Int.J.Mod.Phys.B12:591-600,1998 | 10.1142/S0217979298000351 | null | quant-ph | null | Considerations of feasibility of quantum computing lead to the study of
multispin quantum gates in which the input and output two-state systems (spins)
are not identical. We provide a general discussion of this approach and then
propose an explicit two-spin interaction Hamiltonian which accomplishes the
quantum XOR gate function for a system of three spins: two input and one
output.
| [
{
"version": "v1",
"created": "Sat, 5 Oct 1996 13:07:43 GMT"
}
] | 2014-11-18T00:00:00 | [
[
"Mozyrsky",
"Dima",
""
],
[
"Privman",
"Vladimir",
""
],
[
"Hotaling",
"Steven P.",
""
]
] |
quant-ph/9610009 | Steven Brumby | S.P. Brumby and G.C. Joshi | Experimental status of quaternionic quantum mechanics | 8 pages, no figures, revtex. An update of paper appearing in journal
reference given below, with minor amendments and latest additional references | Chaos Solitons Fractals 7 (1996) 747-752 | 10.1016/0960-0779(95)00001-1 | UM-P-94/120; RCHEP-94/34 | quant-ph hep-ph hep-th | null | Analysis of the logical foundations of quantum mechanics indicates the
possibility of constructing a theory using quaternionic Hilbert spaces. Whether
this mathematical structure reflects reality is a matter for experiment to
decide. We review the only direct search for quaternionic quantum mechanics yet
carried out and outline a recent proposal by the present authors to look for
quaternionic effects in correlated multi-particle systems. We set out how such
experiments might distinguish between the several quaternionic models proposed
in the literature.
| [
{
"version": "v1",
"created": "Tue, 8 Oct 1996 01:20:43 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Brumby",
"S. P.",
""
],
[
"Joshi",
"G. C.",
""
]
] |
quant-ph/9610010 | Gary Oas | Patrick Suppes, J. Acacio de Barros, Gary Oas | A Collection of Probabilistic Hidden-Variable Theorems and
Counterexamples | 20 pages latex. To appear in Nuovo Cimento. Presented Sept. 17, 1996
in Florence at a symposium in honor of Giuliano Toraldo di Francia.
Significant additions and corrections have been made. Additional conditions
on the existence of joint probability distributions as well as theorems on
mapping from higher spin systems to two state variables | null | null | null | quant-ph | null | The purpose of this article is to formulate a number of probabilistic
hidden-variable theorems, to provide proofs in some cases, and counterexamples
to some conjectured relationships. The first theorem is the fundamental one. It
asserts the general equivalence of the existence of a hidden variable and the
existence of a joint probability distribution of the observed quatities,
whether finite or continuous.
| [
{
"version": "v1",
"created": "Tue, 8 Oct 1996 23:05:12 GMT"
},
{
"version": "v2",
"created": "Tue, 18 Feb 1997 19:37:57 GMT"
}
] | 2008-02-03T00:00:00 | [
[
"Suppes",
"Patrick",
""
],
[
"de Barros",
"J. Acacio",
""
],
[
"Oas",
"Gary",
""
]
] |
quant-ph/9610011 | Emanuel Knill | E. Knill, R. Laflamme, W. Zurek | Threshold Accuracy for Quantum Computation | 20 pages. 10/15/96: Added references to threshold results by Aharanov
and Ben-Or and by Kitaev | null | null | null | quant-ph | null | We have previously (quant-ph/9608012) shown that for quantum memories and
quantum communication, a state can be transmitted over arbitrary distances with
error $\epsilon$ provided each gate has error at most $c\epsilon$. We discuss a
similar concatenation technique which can be used with fault tolerant networks
to achieve any desired accuracy when computing with classical initial states,
provided a minimum gate accuracy can be achieved. The technique works under
realistic assumptions on operational errors. These assumptions are more general
than the stochastic error heuristic used in other work. Methods are proposed to
account for leakage errors, a problem not previously recognized.
| [
{
"version": "v1",
"created": "Tue, 8 Oct 1996 19:50:12 GMT"
},
{
"version": "v2",
"created": "Wed, 9 Oct 1996 05:07:19 GMT"
},
{
"version": "v3",
"created": "Tue, 15 Oct 1996 23:27:18 GMT"
}
] | 2008-02-03T00:00:00 | [
[
"Knill",
"E.",
""
],
[
"Laflamme",
"R.",
""
],
[
"Zurek",
"W.",
""
]
] |
quant-ph/9610012 | Emanuel Knill | E. Knill | Quantum Randomness and Nondeterminism | 8 pages | null | null | null | quant-ph | null | Does the notion of a quantum randomized or nondeterministic algorithm make
sense, and if so, does quantum randomness or nondeterminism add power? Although
reasonable quantum random sources do not add computational power, the
discussion of quantum randomness naturally leads to several definitions of the
complexity of quantum states. Unlike classical string complexity, both
deterministic and nondeterministic quantum state complexities are interesting.
A notion of \emph{total quantum nondeterminism} is introduced for decision
problems. This notion may be a proper extension of classical nondeterminism.
| [
{
"version": "v1",
"created": "Wed, 9 Oct 1996 16:32:10 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Knill",
"E.",
""
]
] |
quant-ph/9610013 | Salman Habib | Fred Cooper, John Dawson, Salman Habib, and Robert D. Ryne | Chaos in Time Dependent Variational Approximations to Quantum Dynamics | 10 pages (12 figures), RevTeX (plus macro), uses epsf, minor typos
corrected | Phys.Rev.E57:1489-1498,1998 | 10.1103/PhysRevE.57.1489 | LA-UR-96-3335 | quant-ph chao-dyn nlin.CD | null | Dynamical chaos has recently been shown to exist in the Gaussian
approximation in quantum mechanics and in the self-consistent mean field
approach to studying the dynamics of quantum fields. In this study, we first
show that any variational approximation to the dynamics of a quantum system
based on the Dirac action principle leads to a classical Hamiltonian dynamics
for the variational parameters. Since this Hamiltonian is generically nonlinear
and nonintegrable, the dynamics thus generated can be chaotic, in distinction
to the exact quantum evolution. We then restrict attention to a system of two
biquadratically coupled quantum oscillators and study two variational schemes,
the leading order large N (four canonical variables) and Hartree (six canonical
variables) approximations. The chaos seen in the approximate dynamics is an
artifact of the approximations: this is demonstrated by the fact that its onset
occurs on the same characteristic time scale as the breakdown of the
approximations when compared to numerical solutions of the time-dependent
Schrodinger equation.
| [
{
"version": "v1",
"created": "Wed, 9 Oct 1996 17:12:42 GMT"
},
{
"version": "v2",
"created": "Wed, 16 Oct 1996 23:19:38 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Cooper",
"Fred",
""
],
[
"Dawson",
"John",
""
],
[
"Habib",
"Salman",
""
],
[
"Ryne",
"Robert D.",
""
]
] |
quant-ph/9610014 | H. Dieter Zeh | H. D. Zeh (University of Heidelberg, Germany) | What is achieved by decoherence? | 10 pages, Latex | null | null | null | quant-ph gr-qc hep-ph | null | A short critical review of the concept of decoherence, its consequences, and
its possible implications for the interpretation of quantum theory is given.
| [
{
"version": "v1",
"created": "Thu, 10 Oct 1996 09:33:18 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Zeh",
"H. D.",
"",
"University of Heidelberg, Germany"
]
] |
quant-ph/9610015 | Martin Plenio | M.B. Plenio and P.L. Knight (Imperial College, London, England) | Decoherence limits to quantum computation using trapped ions | 23 pages + 11 pictures | Proc.Roy.Soc.Lond. A453 (1997) 2017-2041 | 10.1098/rspa.1997.0109 | null | quant-ph | null | We investigate the problem of factorization of large numbers on a quantum
computer which we imagine to be realized within a linear ion trap. We derive
upper bounds on the size of the numbers that can be factorized on such a
quantum computer. These upper bounds are independent of the power of the
applied laser. We investigate two possible ways to implement qubits, in
metastable optical transitions and in Zeeman sublevels of a stable ground
state, and show that in both cases the numbers that can be factorized are not
large enough to be of practical interest. We also investigate the effect of
quantum error correction on our estimates and show that in realistic systems
the impact of quantum error correction is much smaller than expected. Again no
number of practical interest can be factorized.
| [
{
"version": "v1",
"created": "Thu, 10 Oct 1996 18:45:47 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Plenio",
"M. B.",
"",
"Imperial College, London, England"
],
[
"Knight",
"P. L.",
"",
"Imperial College, London, England"
]
] |
quant-ph/9610016 | Vladimir Kisil | Oleg V. Prezhdo and Vladimir V. Kisil | Mixing Quantum and Classical Mechanics | 31 pages, LaTeX2e | Phys.Rev. A56 (1997) 162-176 | 10.1103/PhysRevA.56.162 | null | quant-ph funct-an math.FA | null | Using a group theoretical approach we derive an equation of motion for a
mixed quantum-classical system. The quantum-classical bracket entering the
equation preserves the Lie algebra structure of quantum and classical
mechanics: The bracket is antisymmetric and satisfies the Jacobi identity, and,
therefore, leads to a natural description of interaction between quantum and
classical degrees of freedom. We apply the formalism to coupled quantum and
classical oscillators and show how various approximations, such as the
mean-field and the multiconfiguration mean-field approaches, can be obtained
from the quantum-classical equation of motion.
| [
{
"version": "v1",
"created": "Fri, 11 Oct 1996 13:20:12 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Prezhdo",
"Oleg V.",
""
],
[
"Kisil",
"Vladimir V.",
""
]
] |
quant-ph/9610017 | Emily Kracklauer | A. F. Kracklauer | Dichotomic Functions and Bell's Theorems | 4 pages, plain.tex, to appear in the Proceedings of the II Int.
Symposium on Fundamental Problems in Quantum Physics, Kluwer AP | null | null | null | quant-ph | null | It is shown that correlations of dichotomic functions can not conform to
results from Quantum Mechanics. Also, it is seen that the assumptions attendant
to optical tests of Bell's Inequalities actually are consistent with classical
physics so that in conclusion, Bell's Theorems do not preclude hidden variable
interpretations of Quantum Mechanics.
| [
{
"version": "v1",
"created": "Fri, 11 Oct 1996 16:15:28 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Kracklauer",
"A. F.",
""
]
] |
quant-ph/9610018 | null | Y. S. Kim | Wavelets and Information-preserving Transformations | 8 pages, latex, no figures; presented at the 3rd International
Conference on Quantum Communications and Measurements (Fiji-Hakone Land,
Japan, September, 1996), to be published in the Proceedings | null | null | null | quant-ph hep-th | null | The underlying mathematics of the wavelet formalism is a representation of
the inhomogeneous Lorentz group or the affine group. Within the framework of
wavelets, it is possible to define the ``window'' which allows us to introduce
a Lorentz-covariant cut-off procedure. The window plays the central role in
tackling the problem of photon localization. It is possible to make a
transition from light waves to photons through the window. On the other hand,
the windowed wave function loses analyticity. This loss of analyticity can be
measured in terms of entropy difference. It is shown that this entropy
difference can be defined in a Lorentz-invariant manner within the framework of
the wavelet formalism.
| [
{
"version": "v1",
"created": "Sun, 13 Oct 1996 22:08:42 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Kim",
"Y. S.",
""
]
] |
quant-ph/9610019 | Bronius Kaulakys | B. Kaulakys | Quantum dynamics with intermediate measurements in agreement with the
classical dynamics | 5 pages, LaTex, no figures, to be published in Quantum Systems: New
Trends and Methods, World Scientific, Proc. of the Intern. Workshop, Minsk,
Belarus, June 3 - 7, 1996 | null | null | null | quant-ph chao-dyn nlin.CD | null | The effect of repetitive measurement for quantum dynamics of driven by an
intensive external force of the simple few-level systems as well as of the
multilevel systems that exhibit the quantum localisation of classical chaos is
investigated. Frequent measurement of the simple system yields to the quantum
Zeno effect while that of the suppressed quantum system, which classical
counterpart exhibits chaos, results in the delocalisation of the quantum
suppression. From the analysis we may conclude that continuously observable
quasiclassical system evolves essentially classically-like.
| [
{
"version": "v1",
"created": "Mon, 14 Oct 1996 13:23:12 GMT"
}
] | 2008-02-03T00:00:00 | [
[
"Kaulakys",
"B.",
""
]
] |
quant-ph/9610020 | Marcelo Trindade dos Santos S. | M. Trindade dos Santos and M. C. Nemes | Quantum Corrections to the Classical Dynamics: Application to the SU(2)
Lipkin Model | 25 pages, LaTeX, 11 (new version) figures | null | null | IFUSP/P-1235 | quant-ph chao-dyn hep-th nlin.CD | null | We show how nonrelativistic many body techniques can be used to study quantum
corrections to the classical limit, in particular of the $SU(2)$ Lipkin Model.
We show that the quantum corrections are essentially of two types: unitary and
nonunitary. In this work we perform a detailed study of the unitary
corrections. They can be cast in Hamiltonian form and are shown to double the
number of degrees of freedom. As a consequence chaotic behavior emerges. We
show that this semiquantal chaos is the mechanism trough which tunneling is
effected. We also show that these corrections systematically improve the
classical results and propose some quantitative measure of this improvement.
| [
{
"version": "v1",
"created": "Mon, 14 Oct 1996 18:26:39 GMT"
},
{
"version": "v2",
"created": "Tue, 15 Oct 1996 17:29:27 GMT"
},
{
"version": "v3",
"created": "Wed, 16 Oct 1996 19:38:49 GMT"
},
{
"version": "v4",
"created": "Fri, 18 Oct 1996 15:34:31 GMT"
}
] | 2008-02-03T00:00:00 | [
[
"Santos",
"M. Trindade dos",
""
],
[
"Nemes",
"M. C.",
""
]
] |
quant-ph/9610021 | Hong-Chen FU | Hong-Chen Fu and Ryu Sasaki | Hypergeometric States and Their Nonclassical Properties | 17 pages, latex, 7 EPS figures | J.Math.Phys.38:2154-2166,1997 | 10.1063/1.531965 | YITP-96-52 | quant-ph | null | `Hypergeometric states', which are a one-parameter generalization of binomial
states of the single-mode quantized radiation field, are introduced and their
nonclassical properties are investigated. Their limits to the binomial states
and to the coherent and number states are studied. The ladder operator
formulation of the hypergeometric states is found and the algebra involved
turns out to be a one-parameter deformation of $su(2)$ algebra. These states
exhibit highly nonclassical properties, like sub-Poissonian character,
antibunching and squeezing effects. The quasiprobability distributions in phase
space, namely the $Q$ and the Wigner functions are studied in detail. These
remarkable properties seem to suggest that the hypergeometric states deserve
further attention from theoretical and applicational sides of quantum optics.
| [
{
"version": "v1",
"created": "Wed, 16 Oct 1996 01:17:32 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Fu",
"Hong-Chen",
""
],
[
"Sasaki",
"Ryu",
""
]
] |
quant-ph/9610022 | Hong-Chen FU | Hong-Chen Fu and Ryu Sasaki | Negative Binomial and Multinomial States: probability distributions and
coherent states | 24 pages, latex, no figures | J.Math.Phys. 38 (1997) 3968-3987 | 10.1063/1.532102 | YITP-96-53 | quant-ph | null | Following the relationship between probability distribution and coherent
states, for example the well known Poisson distribution and the ordinary
coherent states and relatively less known one of the binomial distribution and
the $su(2)$ coherent states, we propose ``interpretation'' of $su(1,1)$ and
$su(r,1)$ coherent states ``in terms of probability theory''. They will be
called the ``negative binomial'' (``multinomial'') ``states'' which correspond
to the ``negative'' binomial (multinomial) distribution, the non-compact
counterpart of the well known binomial (multinomial) distribution. Explicit
forms of the negative binomial (multinomial) states are given in terms of
various boson representations which are naturally related to the probability
theory interpretation. Here we show fruitful interplay of probability theory,
group theory and quantum theory.
| [
{
"version": "v1",
"created": "Wed, 16 Oct 1996 01:59:50 GMT"
}
] | 2016-09-08T00:00:00 | [
[
"Fu",
"Hong-Chen",
""
],
[
"Sasaki",
"Ryu",
""
]
] |
quant-ph/9610023 | Chau Hoi Fung | H. F. Chau | Correcting Quantum Errors In Higher Spin Systems | In REVTEX 3.0, requires AMS fonts. Typos corrected. To appear in PRA
(Rapid Comm.) | null | 10.1103/PhysRevA.55.R839 | HKUPHYS-HFC-01 | quant-ph | null | I consider the theory of quantum error correcting code (QECC) where each
quantum particle has more than two possible eigenstates. In this higher spin
system, I report an explicit QECC that is related to the symmetry group ${\Bbb
Z}_2^{\otimes (N-1)} \otimes S_N$. This QECC, which generalizes Shor's simple
majority vote code, is able to correct errors arising from exactly one quantum
particle. I also provide a simple encoding algorithm.
| [
{
"version": "v1",
"created": "Wed, 16 Oct 1996 09:51:50 GMT"
},
{
"version": "v2",
"created": "Sun, 1 Dec 1996 06:34:12 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Chau",
"H. F.",
""
]
] |
quant-ph/9610024 | Hong-Chen FU | Hong-Chen Fu and Ryu Sasaki | Negative Binomial States of Quantized Radiation Fields | 10 pages, latex2e, 2 EPS figures | J.Phys.Soc.Jap.66:1989-1994,1997 | 10.1143/JPSJ.66.1989 | YITP-96-54 | quant-ph | null | We introduce the negative binomial states with negative binomial distribution
as their photon number distribution. They reduce to the ordinary coherent
states and Susskind-Glogower phase states in different limits. The ladder and
displacement operator formalisms are found and they are essentially the
Perelomov's su(1,1) coherent states via its Holstein-Primakoff realisation.
These states exhibit strong squeezing effect and they obey the super-Poissonian
statistics. A method to generate these states is proposed.
| [
{
"version": "v1",
"created": "Thu, 17 Oct 1996 01:40:26 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Fu",
"Hong-Chen",
""
],
[
"Sasaki",
"Ryu",
""
]
] |
quant-ph/9610025 | Larry Horwitz | L.P. Horwitz, E. Eisenberg and Y. Strauss | Lax-Phillips Theory and Quantum Evolution | TeX, 16 pages. Proceedings of Quantum Structures '96 Berlin, July
29-Aug. 3, 1996, Technische Univ. Berlin. Report TAUP 2378-96 | null | null | null | quant-ph | null | The scattering theory of Lax and Phillips, designed primarily for hyperbolic
systems, such as electromagnetic or acoustic waves, is described. This theory
provides a realization of the theorem of Foias and Nagy; there is a subspace of
the Hilbert space in which the unitary evolution of the system, restricted to
this subspace, is realized as a semigroup. The embedding of the quantum theory
into this structure, carried out by Flesia and Piron, is reviewed. We show how
the density matrix for an effectively pure state can evolve to an effectively
mixed state (decoherence) in this framework. Necessary conditions are given for
the realization of the relation between the spectrum of the generator of the
semigroup and the singularities of the $S$-matrix (in energy representation).
It is shown that these conditions may be met in the Liouville space formulation
of quantum evolution, and in the Hilbert space of relativistic quantum theory.
| [
{
"version": "v1",
"created": "Thu, 17 Oct 1996 10:29:57 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Horwitz",
"L. P.",
""
],
[
"Eisenberg",
"E.",
""
],
[
"Strauss",
"Y.",
""
]
] |
quant-ph/9610026 | Paul Benioff | Paul Benioff (Argonne National Lab) | Tight Binding Hamiltonians and Quantum Turing Machines | 4 pages Latex, 2 postscript figures, submitted to Phys Rev Letters | Phys.Rev.Lett.78:590-593,1997 | 10.1103/PhysRevLett.78.590 | null | quant-ph cond-mat | null | This paper extends work done to date on quantum computation by associating
potentials with different types of computation steps. Quantum Turing machine
Hamiltonians, generalized to include potentials, correspond to sums over tight
binding Hamiltonians each with a different potential distribution. Which
distribution applies is determined by the initial state. An example, which
enumerates the integers in succession as binary strings, is analyzed. It is
seen that for some initial states the potential distributions have
quasicrystalline properties and are similar to a substitution sequence.
| [
{
"version": "v1",
"created": "Thu, 17 Oct 1996 15:21:21 GMT"
}
] | 2009-01-23T00:00:00 | [
[
"Benioff",
"Paul",
"",
"Argonne National Lab"
]
] |
quant-ph/9610027 | Dr. Luca Salasnich, . D. | Marko Robnik and Luca Salasnich | WKB to all orders and the accuracy of the semiclassical quantization | Latex, 11 pages, submitted to J. Phys. A | J.Phys.A30:1711-1718,1997 | 10.1088/0305-4470/30/5/031 | Preprint CAMTP/96-5, University of Maribor | quant-ph hep-th nucl-th | null | We perform a systematic WKB expansion to all orders for a one-dimensional
system with potential $V(x)=U_0/\cos^2{(\alpha x)}$. We are able to sum the
series to the exact energy spectrum. Then we show that at any finite order the
error of the WKB approximation measured in the natural units of the mean energy
level spacing does not go to zero when the quantum number goes to infinity.
Therefore we make the general conclusion that the semiclassical approximations
fail to predict the individual energy levels within a vanishing fraction of the
mean energy level spacing.
| [
{
"version": "v1",
"created": "Fri, 18 Oct 1996 16:32:25 GMT"
}
] | 2016-09-08T00:00:00 | [
[
"Robnik",
"Marko",
""
],
[
"Salasnich",
"Luca",
""
]
] |
quant-ph/9610028 | Arkadiusz Jadczyk | Ph. Blanchard (Bielefeld) and A. Jadczyk (Wroclaw) | Relativistic Quantum Events | 17 pages, Latex, submitted to Found.Phys | Found.Phys. 26 (1996) 1669-1681 | 10.1007/BF02282128 | BiBoS 737/10/96 | quant-ph | null | We extend the ideas of L.P. Horwitz and C. Piron and we propose a
relativistic version of Event Enhanced Quantum Theory, with an event generating
algorithm for spin one-half particle detectors. The algorithm is based on
proper time formulation of the relativistic quantum theory. Although we use
indefinite metric, all the probabilities controlling the random process of the
detector clicks are non--negative.
| [
{
"version": "v1",
"created": "Fri, 18 Oct 1996 18:23:22 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Blanchard",
"Ph.",
"",
"Bielefeld"
],
[
"Jadczyk",
"A.",
"",
"Wroclaw"
]
] |
quant-ph/9610029 | Haret Rosu | H.C. Rosu, J. Socorro | Note on the Demkov-Ostrovsky nodeless sector | 6 pages, LaTex, 3 figs included | Nuovo Cimento B 113 (February 1998) 267-270 | null | null | quant-ph | null | We briefly tackle the following concepts in the Demkov-Ostrovsky (DO)
nodeless sector: (i) orbital impedance, (ii) orbital capacity, (iii) closeness
to reflectionlessness. Moreover, using previous supersymmetric results for the
DO problem, a strictly isospectral effect in the DO orbital impedances is
discussed and explicit plots are displayed for the Maxwell fisheye lens. This
effect, though rather small, is general, that is, it may apply to any focusing
structure.
| [
{
"version": "v1",
"created": "Sat, 19 Oct 1996 19:48:00 GMT"
},
{
"version": "v2",
"created": "Tue, 22 Oct 1996 23:41:00 GMT"
},
{
"version": "v3",
"created": "Wed, 23 Oct 1996 00:52:00 GMT"
},
{
"version": "v4",
"created": "Sat, 25 Oct 1997 18:54:47 GMT"
},
{
"version": "v5",
"created": "Fri, 17 Apr 1998 18:57:43 GMT"
}
] | 2008-02-03T00:00:00 | [
[
"Rosu",
"H. C.",
""
],
[
"Socorro",
"J.",
""
]
] |
quant-ph/9610030 | Peter Leifer | Peter Leifer | Superrelativity as a unification of quantum theory and relativity | 21 pages,Latex | null | null | TAUP 10-96 | quant-ph | null | Principle of ``Superrelativity'' has been proposed in order to avoid the
contradiction between principle of relativity and foundations of quantum
theory. Solutions of a newly derived non-linear Klein-Gordon equation
presumably may be treated as primordial nonlocal elements of quantum theory. It
is shown that in the framework of CP(N-1) model supplementary elements which
are non-local in spacetime but local in the projective Hilbert space permit us
to avoid at least one of the main difficulties of quantum theory-the necessity
to relate the ``reality'' of a quantum state with a measuring process. In the
framework of superrelativity the geometry of the projective Hilbert space
(Fubini-Study metric and connection) together with the non-linear wave equation
are full and closed quantum scheme.
| [
{
"version": "v1",
"created": "Sun, 20 Oct 1996 21:03:31 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Leifer",
"Peter",
""
]
] |
quant-ph/9610031 | Cassius D'Helon | C. D'Helon and G.J. Milburn | Correcting the effects of spontaneous emission on cold trapped ions | 19 pages; 2 figures; RevTex; The quantum codewords are extended to
achieve invariance under the conditional time evolution between jumps | null | 10.1103/PhysRevA.56.640 | null | quant-ph | null | We propose two quantum error correction schemes which increase the maximum
storage time for qubits in a system of cold trapped ions, using a minimal
number of ancillary qubits. Both schemes consider only the errors introduced by
the decoherence due to spontaneous emission from the upper levels of the ions.
Continuous monitoring of the ion fluorescence is used in conjunction with
selective coherent feedback to eliminate these errors immediately following
spontaneous emission events, and the conditional time evolution between quantum
jumps is removed by symmetrizing the quantum codewords.
| [
{
"version": "v1",
"created": "Mon, 21 Oct 1996 05:10:09 GMT"
},
{
"version": "v2",
"created": "Mon, 13 Jan 1997 07:09:52 GMT"
},
{
"version": "v3",
"created": "Mon, 19 May 1997 06:02:13 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"D'Helon",
"C.",
""
],
[
"Milburn",
"G. J.",
""
]
] |
quant-ph/9610032 | Colin Wilkin | Goeran Faeldt, Colin Wilkin | Scattering Wave Functions at Bound State Poles | 15 pages Latex. No graphs | null | 10.1088/0031-8949/56/6/004 | TSL/ISV-96-0152 | quant-ph nucl-th | null | The normalisation relation between the bound and scattering S-state wave
functions, extrapolated to the bound state pole, is derived from the
Schroedinger equation. It is shown that, unlike previous work, the result does
not depend on the details of the potential through the corresponding Jost
function but is given uniquely in terms of the binding energy. The
generalisations to higher partial waves and one-dimensional scattering are
given.
| [
{
"version": "v1",
"created": "Mon, 21 Oct 1996 09:21:25 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Faeldt",
"Goeran",
""
],
[
"Wilkin",
"Colin",
""
]
] |
quant-ph/9610033 | Lev Vaidman | Lev Vaidman | Interaction-Free Measurements | 7 pages, LaTeX2e, multi3.sty, 5 eps figures | null | null | TAUP 2382-96 | quant-ph | null | A brief review of interaction-free measurements (IFM) is presented. The IFM
is a solution of a quantum puzzle: How to test a bomb which explodes on every
test without exploding it? This paper was given in the Oxford conference in
honor of Roger Penrose.
| [
{
"version": "v1",
"created": "Mon, 21 Oct 1996 12:02:53 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Vaidman",
"Lev",
""
]
] |
quant-ph/9610034 | Claudia C. Eberlein | Claudia Eberlein (Cavendish Lab, Cambridge, England) | Sonoluminescence as Quantum Vacuum Radiation, Reply to Comments | 2 pages, Latex file | null | null | null | quant-ph | null | Reply to Comments by Lambrecht, Jaekel, and Reynaud, and by Garcia and
Levanyuk, submitted to Physical Review Letters.
| [
{
"version": "v1",
"created": "Mon, 21 Oct 1996 21:11:00 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Eberlein",
"Claudia",
"",
"Cavendish Lab, Cambridge, England"
]
] |
quant-ph/9610035 | Walter T. Strunz | Walter T. Strunz | Linear quantum state diffusion for non-Markovian open quantum systems | 9 pages, RevTeX, appears in Physics Letters A | null | 10.1016/S0375-9601(96)00805-5 | QMW-PH-96-17 | quant-ph | null | We demonstrate the relevance of complex Gaussian stochastic processes to the
stochastic state vector description of non-Markovian open quantum systems.
These processes express the general Feynman-Vernon path integral propagator for
open quantum systems as the classical ensemble average over stochastic pure
state propagators in a natural way. They are the coloured generalization of
complex Wiener processes in quantum state diffusion stochastic Schrodinger
equations.
| [
{
"version": "v1",
"created": "Tue, 22 Oct 1996 14:04:53 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Strunz",
"Walter T.",
""
]
] |
quant-ph/9610036 | Huw Price | Huw Price (University of Sydney) | Time Symmetry in Microphysics | 10 pages, Latex. Draft of a paper for a symposium at the Biennial
Meeting of the Philosophy of Science Association, Cleveland, Ohio, 1--3
November, 1996. Also available in html and rtf at
http://plato.stanford.edu/price/preprints/PSA96.html | null | null | null | quant-ph | null | Physics takes for granted that interacting physical systems with no common
history are independent, before their interaction. This principle is
time-asymmetric, for no such restriction applies to systems with no common
future, after an interaction. The time-asymmetry is normally attributed to
boundary conditions. I argue that there are two distinct independence
principles of this kind at work in contemporary physics, one of which cannot be
attributed to boundary conditions, and therefore conflicts with the assumed T
(or CPT) symmetry of microphysics. I note that this may have interesting
ramifications in quantum mechanics.
| [
{
"version": "v1",
"created": "Tue, 22 Oct 1996 23:16:19 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Price",
"Huw",
"",
"University of Sydney"
]
] |
quant-ph/9610037 | Diosi Lajos | Lajos Diosi | Coherent States and the Measurement Problem | 9pp PlainTeX, Eq.(3) and footnote [16] corrected | null | null | null | quant-ph | null | The convenience of coherent state representation is discussed from the
viewpoint of what is in a broad sense called the measurement problem in quantum
mechanics. Standard quantum theory in coherent state representation is
intrinsically related to a number of earlier concepts conciliating quantum and
classical processes. From a natural statistical interpretation, free of
collapses or measurements, the usual von Neumann-L\"uders collapse as well as
its quantum state diffusion interpretation follow. In particular, a theory of
coupled quantum and classical dynamics arises, containing the fluctuation
corrections versus the fenomenological mean-field theories.
| [
{
"version": "v1",
"created": "Wed, 23 Oct 1996 12:19:49 GMT"
},
{
"version": "v2",
"created": "Sat, 25 Jan 1997 17:22:06 GMT"
}
] | 2008-02-03T00:00:00 | [
[
"Diosi",
"Lajos",
""
]
] |
quant-ph/9610038 | Mauro Fortunato | M. Fortunato, G. Kurizki, and W. P. Schleich | Quantum Control of Chaos inside a Cavity | 6 pages, 2 figures. Needs acta96.sty, also included in this
submission. The two figures are included automatically through psfig.sty.
Talk given by Mauro Fortunato at the 4th central-european workshop on quantum
optics, Budmerice, Slovakia, May 31 - June 3, 1996 | Acta Phys.Slov. 46 (1996) 381 | null | null | quant-ph | null | By sending many two-level atoms through a cavity resonant with the atomic
transition, and letting the interaction times between the atoms and the cavity
be randomly distributed, we end up with a predetermined Fock state of the
electromagnetic field inside the cavity if we perform after the interaction
with the cavity a conditional measurement of the internal state of each atom in
a coherent superposition of its ground and excited states. Differently from
previous schemes, this procedure turns out to be very stable under fluctuations
in the interaction times.
| [
{
"version": "v1",
"created": "Wed, 23 Oct 1996 15:31:38 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Fortunato",
"M.",
""
],
[
"Kurizki",
"G.",
""
],
[
"Schleich",
"W. P.",
""
]
] |
quant-ph/9610039 | Yosef Ashkenazy | E. Eisenberg and Y. Ashkenazy | A New Time-Scale for Tunneling | 12 pages + 6 figures, RevTex | Found.Phys. 27 (1997) 191-202 | 10.1007/BF02550449 | null | quant-ph | null | We study the tunneling through an oscillating delta barrier. Using time
periodicity of the model, the time-dependent Schr\"odinger equation is reduced
to a simple but infinite matrix equation. Employing Toeplitz matrices methods,
the infinite matrix is replaces by a $3\times 3$ matrix, allowing an analytical
solution. Looking at the frequency dependence of the transmissionamplitudes,
one observes a new time scale which dominates the tunneling dynamics. This time
scale differs from the one previously introduced by B\"uttiker and Landauer.
The relation between these two is discussed.
| [
{
"version": "v1",
"created": "Fri, 25 Oct 1996 10:54:46 GMT"
},
{
"version": "v2",
"created": "Wed, 27 Nov 1996 17:48:39 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Eisenberg",
"E.",
""
],
[
"Ashkenazy",
"Y.",
""
]
] |
quant-ph/9610040 | Raymond LaFlamme | Peter Shor and Raymond Laflamme | Quantum MacWilliams Identities | 3 pages in RevTex, the paper is also avalaible at
http://qso.lanl.gov/qc/ | null | null | LA-UR 96-3652 | quant-ph | null | We derive a relationship between two different notions of fidelity
(entanglement fidelity and average fidelity) for a completely depolarizing
quantum channel. This relationship gives rise to a quantum analog of the
MacWilliams identities in classical coding theory. These identities relate the
weight enumerator of a code to the one of its dual and, with linear programming
techniques, provided a powerful tool to investigate the possible existence of
codes. The same techniques can be adapted to the quantum case. We give examples
of their power.
| [
{
"version": "v1",
"created": "Fri, 25 Oct 1996 21:32:14 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Shor",
"Peter",
""
],
[
"Laflamme",
"Raymond",
""
]
] |
quant-ph/9610041 | Bronius Kaulakys | B. Kaulakys | Dynamical peculiarities of the nonlinear quasiclassical systems | 4 pages, LaTeX | null | null | null | quant-ph chao-dyn nlin.CD | null | The quantum-classical correspondence for dynamics of the nonlinear
classically chaotic systems is analysed. The problem of quantum chaos consists
of two parts: the quasiclassical quantisation of the chaotic systems and
attempts to understand the classical chaos in terms of quantum mechanics. The
first question has been partially solved by the Gutzwiller semiclassical trace
formula for the eigenvalues of chaotic systems, while the classical chaos may
be derived from quantum equations only introducing the decoherence process due
to interaction with system's environment or intermediate frequent measurement.
We may conclude that continuously observable quasiclassical system evolves
essentially classically-like.
| [
{
"version": "v1",
"created": "Mon, 28 Oct 1996 13:28:30 GMT"
}
] | 2008-02-03T00:00:00 | [
[
"Kaulakys",
"B.",
""
]
] |
quant-ph/9610042 | Markus Grassl | Markus Grassl (1), Thomas Beth (1), Thomas Pellizzari (2) ((1)
Universitaet Karlsruhe, (2) Universitaet Innsbruck) | Codes for the Quantum Erasure Channel | 6 pages, RevTeX, no figures, submitted to Physical Review A, code
extended to encode 2 qubits, references added | Phys. Rev. A, vol. 56, no. 1, July 1997, pp. 33-38 | 10.1103/PhysRevA.56.33 | null | quant-ph | null | The quantum erasure channel (QEC) is considered. Codes for the QEC have to
correct for erasures, i. e., arbitrary errors at known positions. We show that
four qubits are necessary and sufficient to encode one qubit and correct one
erasure, in contrast to five qubits for unknown positions. Moreover, a family
of quantum codes for the QEC, the quantum BCH codes, that can be efficiently
decoded is introduced.
| [
{
"version": "v1",
"created": "Mon, 28 Oct 1996 10:56:53 GMT"
},
{
"version": "v2",
"created": "Fri, 17 Jan 1997 13:28:26 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Grassl",
"Markus",
""
],
[
"Beth",
"Thomas",
""
],
[
"Pellizzari",
"Thomas",
""
]
] |
quant-ph/9610043 | Isaac Chuang | I. L. Chuang, Debbie W. Leung, and Yoshihisa Yamamoto | Bosonic Quantum Codes for Amplitude Damping | 12 pages, 3 figures, psfig, revtex, submitted to Phys. Rev. A | null | 10.1103/PhysRevA.56.1114 | null | quant-ph | null | Traditional quantum error correction involves the redundant encoding of k
quantum bits using n quantum bits to allow the detection and correction of any
t bit error. The smallest general t=1 code requires n=5 for k=1. However, the
dominant error process in a physical system is often well known, thus inviting
the question: given a specific error model, can more efficient codes be
devised? We demonstrate new codes which correct just amplitude damping errors
which allow, for example, a t=1, k=1 code using effectively n=4.6. Our scheme
is based on using bosonic states of photons in a finite number of optical
modes. We present necessary and sufficient conditions for the codes, and
describe construction algorithms, physical implementation, and performance
bounds.
| [
{
"version": "v1",
"created": "Tue, 29 Oct 1996 09:00:25 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Chuang",
"I. L.",
""
],
[
"Leung",
"Debbie W.",
""
],
[
"Yamamoto",
"Yoshihisa",
""
]
] |
quant-ph/9610044 | Daniel Rohrlich | Sandu Popescu and Daniel Rohrlich | Thermodynamics and the Measure of Entanglement | 8 pages, RevTeX; edited for clarity, additional references, to appear
as a Rapid Communication in Phys. Rev. A | null | 10.1103/PhysRevA.56.R3319 | TAUP 2385-96 | quant-ph | null | We point out formal correspondences between thermodynamics and entanglement.
By applying them to previous work, we show that entropy of entanglement is the
unique measure of entanglement for pure states.
| [
{
"version": "v1",
"created": "Tue, 29 Oct 1996 20:06:48 GMT"
},
{
"version": "v2",
"created": "Thu, 11 Sep 1997 21:43:13 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Popescu",
"Sandu",
""
],
[
"Rohrlich",
"Daniel",
""
]
] |
quant-ph/9610045 | Toshifumi Sakaguchi | Toshifumi Sakaguchi | On the EPR Phenomenon | 6 pages, REVTeX, no figures | null | null | null | quant-ph | null | The origin of the nonlocal nature of quantum mechanics is investigated in the
context of Everett's formulation of quantum mechanics. EPR phenomenon can fully
be explained without introducing any kind of decoherence.
| [
{
"version": "v1",
"created": "Wed, 30 Oct 1996 05:17:34 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Sakaguchi",
"Toshifumi",
""
]
] |
quant-ph/9610046 | Tommaso Calarco | Tommaso Calarco (Dipartimento di fisica - INFN, Ferrara, Italy) and
Roberto Onofrio (Dipartimento di fisica - INFN, Padova, Italy) | Quantum nondemolition measurements on two-level atomic systems and
temporal Bell inequalities | 7 pages, 2 figures, to appear in Appl. Phys. B | null | 10.1007/s003400050158 | null | quant-ph | null | The evolution of a two-level system subjected to stimulated transitions which
is undergoing a sequence of measurements of the level occupation probability is
evaluated. Its time correlation function is compared to the one obtained
through the pure Schroedinger evolution. Systems of this kind have been
recently proposed for testing the quantum mechanical predictions against those
of macrorealistic theories, by means of temporal Bell inequalities. The
classical requirement of noninvasivity, needed to define correlation functions
in the realistic case, finds a quantum counterpart in the quantum nondemolition
condition. The consequences on the observability of quantum mechanically
predicted violations to temporal Bell inequalities are drawn and compared to
the already dealt case of the rf-SQUID dynamics.
| [
{
"version": "v1",
"created": "Thu, 31 Oct 1996 12:48:40 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Calarco",
"Tommaso",
"",
"Dipartimento di fisica - INFN, Ferrara, Italy"
],
[
"Onofrio",
"Roberto",
"",
"Dipartimento di fisica - INFN, Padova, Italy"
]
] |
quant-ph/9611001 | null | E. M. Rains (AT&T Research) | Quantum shadow enumerators | AMSTeX, 10 pages, no figures, submitted to IEEE Trans. Inf. Theory
Updated 2/19/97 to reflect strengthening of the n/6 bound to impure codes, as
well as minor typographical changes and bibliographical updates | IEEE Trans.Info.Theor. 45 (1999) 2361-2366 | null | null | quant-ph | null | In a recent paper [quant-ph/9610040], Shor and Laflamme define two ``weight
enumerators'' for quantum error correcting codes, connected by a MacWilliams
transform, and use them to give a linear-programming bound for quantum codes.
We extend their work by introducing another enumerator, based on the classical
theory of shadow codes, that tightens their bounds significantly. In
particular, nearly all of the codes known to be optimal among additive quantum
codes (codes derived from orthogonal geometry ([quant-ph/9608006])) can be
shown to be optimal among all quantum codes. We also use the shadow machinery
to extend a bound on additive codes (E. M. Rains, manuscript in preparation) to
general codes, obtaining as a consequence that any code of length n can correct
at most floor((n+1)/6) errors.
| [
{
"version": "v1",
"created": "Fri, 1 Nov 1996 16:30:00 GMT"
},
{
"version": "v2",
"created": "Wed, 19 Feb 1997 14:50:31 GMT"
}
] | 2008-02-03T00:00:00 | [
[
"Rains",
"E. M.",
"",
"AT&T Research"
]
] |
quant-ph/9611002 | Todd Brun | Nicolas Gisin (Group of Applied Physics, University of Geneva) Todd A.
Brun (Institute for Theoretical Physics, UCSB) Marco Rigo (Maths Department,
Royal Holloway College, London) | From Quantum to Classical: the Quantum State Diffusion Model | 6 pages standard LaTeX + 2 figures (postscript) To appear in the
Proceedings of the 2nd International Conference on Fundamental Problems in
Quantum Physics, Oviedo, Spain, 1996 | null | null | null | quant-ph | null | Quantum mechanics is nonlocal. Classical mechanics is local. Consequently
classical mechanics can not explain all quantum phenomena. Conversely, it is
cumbersome to use quantum mechanics to describe classical phenomena. Not only
are the computations more complex, but - and this is the main point - it is
conceptually more difficult: one has to argue that nonlocality, entanglement
and the principle of superposition can be set aside when crossing the "quantum
$\rightarrow$ classical" border. Clearly, nonlocality, entanglement and the
principle of superposition should become irrelevant in the classical limit. But
why should one argue? Shouldn't it just come out of the equations? Does it come
out of the equations? This contribution is about the last question. And the
answer is: "it depends on which equation".
| [
{
"version": "v1",
"created": "Fri, 1 Nov 1996 19:13:54 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Gisin",
"Nicolas",
"",
"Group of Applied Physics, University of Geneva"
],
[
"Brun",
"Todd A.",
"",
"Institute for Theoretical Physics, UCSB"
],
[
"Rigo",
"Marco",
"",
"Maths Department,\n Royal Holloway College, London"
]
] |
quant-ph/9611003 | Hong-Chen FU | Hong-Chen Fu and Ryu Sasaki | Generally Deformed Oscillator, Isospectral Oscillator System and
Hermitian Phase Operator | 21 pages, latex, no figures | J.Phys.A29:4049,1996 | 10.1088/0305-4470/29/14/027 | null | quant-ph | null | The generally deformed oscillator (GDO) and its multiphoton realization as
well as the coherent and squeezed vacuum states are studied. We discuss, in
particular, the GDO depending on a complex parameter q (therefore we call it
q-GDO) together with the finite dimensional cyclic representations. As a
realistic physical system of GDO the isospectral oscillator system is studied
and it is found that its coherent and squeezed vacuum states are closely
related to those of the oscillator. It is pointed out that starting from the
q-GDO with q root of unity one can define the hermitian phase operators in
quantum optics consistently and algebraically. The new creation and
annihilation operators of the Pegg-Barnett type phase operator theory are
defined by using the cyclic representations and these operators degenerate to
those of the ordinary oscillator in the classical limit q->1.
| [
{
"version": "v1",
"created": "Sat, 2 Nov 1996 03:36:49 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Fu",
"Hong-Chen",
""
],
[
"Sasaki",
"Ryu",
""
]
] |
quant-ph/9611004 | Tad Hogg | Tad Hogg | A Framework for Quantum Search Heuristics | 8 pages, Latex, 5 figures, to appear at PhysComp96, further
information available at ftp://parcftp.xerox.com/pub/dynamics/quantum.html | Proc. of the Workshop on Physics and Computation (PhysComp96), pp.
140-146 (1996) | null | null | quant-ph | null | A quantum algorithm for combinatorial search is presented that provides a
simple framework for utilizing search heuristics. The algorithm is evaluated in
a new case that is an unstructured version of the graph coloring problem. It
performs significantly better than the direct use of quantum parallelism, on
average, in cases corresponding to previously identified phase transitions in
search difficulty. The conditions underlying this improvement are described.
Much of the algorithm is independent of particular problem instances, making it
suitable for implementation as a special purpose device.
| [
{
"version": "v1",
"created": "Mon, 4 Nov 1996 18:55:24 GMT"
}
] | 2009-10-06T00:00:00 | [
[
"Hogg",
"Tad",
""
]
] |
quant-ph/9611005 | David Meyer | David A. Meyer | Quantum mechanics of lattice gas automata. I. One particle plane waves
and potentials | 19 pages, plain TeX, 14 PostScript figures included with epsf.tex
(ignore the under/overfull \vbox error messages), two additional large
figures available upon request | null | 10.1103/PhysRevE.55.5261 | null | quant-ph comp-gas nlin.CG | null | Classical lattice gas automata effectively simulate physical processes such
as diffusion and fluid flow (in certain parameter regimes) despite their
simplicity at the microscale. Motivated by current interest in quantum
computation we recently defined quantum lattice gas automata; in this paper we
initiate a project to analyze which physical processes these models can
effectively simulate. Studying the single particle sector of a one dimensional
quantum lattice gas we find discrete analogues of plane waves and wave packets,
and then investigate their behaviour in the presence of inhomogeneous
potentials.
| [
{
"version": "v1",
"created": "Tue, 5 Nov 1996 00:44:09 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Meyer",
"David A.",
""
]
] |
quant-ph/9611006 | Christopher A. Fuchs | Charles H. Bennett, Christopher A. Fuchs, and John A. Smolin | Entanglement-Enhanced Classical Communication on a Noisy Quantum Channel | 10 pages, LaTeX, to appear in Proceedings of the 3rd International
Workshop on Quantum Communication and Measurement; See also
http://vesta.physics.ucla.edu/~smolin/ | null | null | null | quant-ph | null | We consider the problem of trying to send a single classical bit through a
noisy quantum channel when two transmissions through the channel are available
as a resource. Classically, two transmissions add nothing to the receiver's
capability of inferring the bit. In the quantum world, however, one has the
possible further advantage of entangling the two transmissions. We demonstrate
that, for certain noisy channels, such entangled transmissions enhance the
receiver's capability of a correct inference.
| [
{
"version": "v1",
"created": "Tue, 5 Nov 1996 04:24:00 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bennett",
"Charles H.",
""
],
[
"Fuchs",
"Christopher A.",
""
],
[
"Smolin",
"John A.",
""
]
] |
quant-ph/9611007 | Imafuku Kentaro | Kentaro Imafuku (Department of Physics, Waseda University), Ichiro
Ohba (Department of Physics, Waseda University) and Yoshiya Yamanaka (Waseda
University Senior High School) | Effects of Inelastic Scattering on Tunneling Time in Generalized
Nelson's Quantum Mechanics | 25 pages, 10 Postscript figures | null | null | WU-HEP-96-8 | quant-ph | null | We analyze the effects of inelastic scattering on the tunneling time
theoretically, using generalized Nelson's quantum mechanics. This
generalization enables us to describe quantum system with optical potential and
channel couplings in a real time stochastic approach, which seems to give us a
new insight into quantum mechanics beyond Copenhagen interpretation.
| [
{
"version": "v1",
"created": "Wed, 6 Nov 1996 04:06:07 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Imafuku",
"Kentaro",
"",
"Department of Physics, Waseda University"
],
[
"Ohba",
"Ichiro",
"",
"Department of Physics, Waseda University"
],
[
"Yamanaka",
"Yoshiya",
"",
"Waseda\n University Senior High School"
]
] |
quant-ph/9611008 | James R. Anglin | James Anglin | Cold, dilute, trapped bosons as an open quantum system | 4 pages, RevTeX twocolumn style | Phys.Rev.Lett. 79 (1997) 6-9 | 10.1103/PhysRevLett.79.6 | LA-UR 96-3873 | quant-ph cond-mat.stat-mech | null | We present a master equation governing the reduced density operator for a
single trapped mode of a cold, dilute, weakly interacting Bose gas; and we
obtain an operator fluctuation-dissipation relation in which the
Ginzburg-Landau effective potential plays a physically transparent role. We
also identify a decoherence effect that tends to preserve symmetry, even when
the effective potential has a ``Mexican hat'' form.
| [
{
"version": "v1",
"created": "Wed, 6 Nov 1996 22:15:44 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Anglin",
"James",
""
]
] |
quant-ph/9611009 | Werner Hofer | W. A. Hofer (TU Wien) | Beyond Uncertainty: the internal structure of electrons and photons | 24 pages (RevTeX, twocolumn) and 2 figures (eps). Modifications and
additions in section IV/K (particle spin) to improve on readability and
conciseness (only verbal) | null | null | null | quant-ph hep-th | null | The wave-structure of moving electrons is analyzed on a fundamental level by
employing a modified de Broglie relation. Formalizing the wave-function $\psi$
in real notation yields internal energy components due to mass oscillations.
The wave-features can then be referred to physical waves of discrete frequency
$\nu$ and the classical dispersion relation $\lambda \nu = u $, complying with
the classical wave equation. Including external potentials yields the
Schr\"odinger equation, which, in this context, is arbitrary due to the
internal energy components. It can be established that the uncertainty
relations are an expression of this, fundamental, arbitrariness. Electrons and
photons can be described by an identical formalism, providing formulations
equivalent to the Maxwell equations. The wave equations of intrinsic particle
properties are Lorentz invariant considering total energy of particles,
although transformations into a moving reference frame lead to an increase of
intrinsic potentials. Interactions of photons and electrons are treated
extensively, the results achieved are equivalent to the results in quantum
theory. Electrostatic interactions provide, a posteriori, a justification for
the initial assumption of electron-wave stability: the stability of electron
waves can be referred to vanishing intrinsic fields of interaction. The concept
finally allows the conclusion that a significant correlation for a pair of spin
particles in EPR--like measurements is likely to violate the uncertainty
relations.
| [
{
"version": "v1",
"created": "Thu, 7 Nov 1996 18:26:33 GMT"
},
{
"version": "v2",
"created": "Thu, 28 Nov 1996 14:00:40 GMT"
},
{
"version": "v3",
"created": "Thu, 17 Apr 1997 08:38:48 GMT"
}
] | 2008-02-03T00:00:00 | [
[
"Hofer",
"W. A.",
"",
"TU Wien"
]
] |
quant-ph/9611010 | Christopher Fuchs | Christopher A. Fuchs | Information Gain vs. State Disturbance in Quantum Theory | 19 pages, LaTeX, requires pac96sty.tex. Full paper submitted to
PhysComp96, eventually to appear in special issue of Physica D | null | null | BOCK-1 | quant-ph | null | The engine that powers quantum cryptography is the principle that there are
no physical means for gathering information about the identity of a quantum
system's state (when it is known to be prepared in one of a set of
nonorthogonal states) without disturbing the system in a statistically
detectable way. This situation is often mistakenly described as a consequence
of the ``Heisenberg uncertainty principle.'' A more accurate account is that it
is a unique feature of quantum phenomena that rests ultimately on the Hilbert
space structure of the theory along with the fact that time evolutions for
isolated systems are unitary. In this paper we shall explore several aspects of
the information--disturbance principle in an attempt to make it firmly
quantitative and flesh out its significance for quantum theory as a whole.
| [
{
"version": "v1",
"created": "Thu, 7 Nov 1996 16:33:32 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Fuchs",
"Christopher A.",
""
]
] |
quant-ph/9611011 | Asher Peres | David P. DiVincenzo and Asher Peres | Quantum codewords contradict local realism | 9 pages LaTeX, 1 figure | Phys.Rev.A55:4089,1997 | 10.1103/PhysRevA.55.4089 | null | quant-ph | null | Quantum codewords are highly entangled combinations of two-state systems. The
standard assumptions of local realism lead to logical contradictions similar to
those found by Bell, Kochen and Specker, Greenberger, Horne and Zeilinger, and
Mermin. The new contradictions have some noteworthy features that did not
appear in the older ones.
| [
{
"version": "v1",
"created": "Fri, 8 Nov 1996 20:07:38 GMT"
}
] | 2008-12-18T00:00:00 | [
[
"DiVincenzo",
"David P.",
""
],
[
"Peres",
"Asher",
""
]
] |
quant-ph/9611012 | Boris F. Samsonov | Boris F. Samsonov | New features in supersymmetry breakdown in quantum mechanics | 5 pages, latex, amsfonts | Mod.Phys.Lett. A11 (1996) 1563-1567 | 10.1142/S0217732396001557 | null | quant-ph | null | The supersymmetric quantum mechanical model based on higher-derivative
supercharge operators possessing unbroken supersymmetry and discrete energies
below the vacuum state energy is described. As an example harmonic oscillator
potential is considered.
| [
{
"version": "v1",
"created": "Sun, 10 Nov 1996 05:49:50 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Samsonov",
"Boris F.",
""
]
] |
quant-ph/9611013 | Juan Fernando Poyatos | J. F. Poyatos, J. I. Cirac (Departamento de Fisica Aplicada,
Universidad de Castilla--La Mancha, Ciudad Real, Spain), P. Zoller (Institut
fuer Theoretische Physik, Universitaet Innsbruck, Austria) | Complete Characterization of a Quantum Process: the Two-Bit Quantum Gate | Accepted for publication in Physical Review Letters 08Nov96
(submitted 15Jly96) | null | 10.1103/PhysRevLett.78.390 | null | quant-ph | null | We show how to fully characterize a quantum process in an open quantum
system. We particularize the procedure to the case of a universal two-qubit
gate in a quantum computer. We illustrate the method with a numerical
simulation of a quantum gate in the ion trap quantum computer.
| [
{
"version": "v1",
"created": "Sun, 10 Nov 1996 10:56:29 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Poyatos",
"J. F.",
"",
"Departamento de Fisica Aplicada,\n Universidad de Castilla--La Mancha, Ciudad Real, Spain"
],
[
"Cirac",
"J. I.",
"",
"Departamento de Fisica Aplicada,\n Universidad de Castilla--La Mancha, Ciudad Real, Spain"
],
[
"Zoller",
"P.",
"",
"Institut\n fuer Theoretische Physik, Universitaet Innsbruck, Austria"
]
] |
quant-ph/9611014 | Arvind | Arvind, N. Mukunda (Indian Institute of Science, Bangalore, India) and
R. Simon (Institute of Mathematical Sciences, Madras, India) | Gaussian Wigner distributions and hierarchies of nonclassical states in
quantum optics-The single mode case | 11 Pages Revtex one eps figure. Replaced with minor changes in refs | Phys.Rev.A56:5042-5052,1997 | 10.1103/PhysRevA.56.5042 | null | quant-ph | null | A recently introduced hierarchy of states of a single mode quantised
radiation field is examined for the case of centered Guassian Wigner
distributions. It is found that the onset of squeezing among such states
signals the transition to the strongly nonclassical regime. Interesting
consequences for the photon number distribution, and explicit representations
for them, are presented.
| [
{
"version": "v1",
"created": "Sun, 10 Nov 1996 12:15:11 GMT"
},
{
"version": "v2",
"created": "Mon, 18 Nov 1996 10:31:25 GMT"
}
] | 2008-12-18T00:00:00 | [
[
"Arvind",
"",
"",
"Indian Institute of Science, Bangalore, India"
],
[
"Mukunda",
"N.",
"",
"Indian Institute of Science, Bangalore, India"
],
[
"Simon",
"R.",
"",
"Institute of Mathematical Sciences, Madras, India"
]
] |
quant-ph/9611015 | Riccardo Giannitrapani | Riccardo Giannitrapani | Positive-Operator-Valued Time Observable in Quantum Mechanics | 13 pages, LaTeX, no figures. Some minor changes, expanded the
bibliography (now it is bigger than the one in the published version),
changed the title and the style for publication on the International Journal
of Theoretical Physics | International Journal of Theoretical Physics 36, 1575 (1997) | 10.1007/BF02435757 | UTF-390 | quant-ph gr-qc | null | We examine the longstanding problem of introducing a time observable in
Quantum Mechanics; using the formalism of positive-operator-valued measures we
show how to define such an observable in a natural way and we discuss some
consequences.
| [
{
"version": "v1",
"created": "Mon, 11 Nov 1996 08:54:52 GMT"
},
{
"version": "v2",
"created": "Fri, 13 Feb 1998 10:08:04 GMT"
},
{
"version": "v3",
"created": "Sun, 22 Feb 1998 12:45:32 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Giannitrapani",
"Riccardo",
""
]
] |
quant-ph/9611016 | Daniel I. Fivel | Daniel I. Fivel | A Dynamical Reduction Theory of Einstein-Podolsky-Rosen Correlations and
a Possible Origin of CP Violations | 30 pages, 0 figures, LaTeX | null | 10.1103/PhysRevA.56.146 | null | quant-ph | null | We show that there is essentially only one way to construct a stochastic
Schrodinger equation that gives a dynamical account of the transformation of
entangled into factorized states and is consistent both with quantum mechanics
and required symmetries. The noisy, non-linear term is a unimodular scalar
multiple of the time reversal operator that must be present whenever a
Hamiltonian term in the Schrodinger equation can distinguish the factorized
constituents of an entangled state. The dynamical mechanism involved in the
transformation of entangled into factorized states provides an explanation for
the fact that Einstein-Podolsky-Rosen correlations appear in a time determined
by the response of the measuring device and independent of the distance between
the particles. The dependence on the response time of the measuring device may
be testable through a delay in observing the collapse of mesoscopic
``Schrodinger cat" states in ion traps. It is further shown that there are
situations where a two-particle interaction can induce a non-linear term by
virtue of coupling to decay modes that distinguish factorized constituents of
an entangled state. We show that this should happen in the neutral K-meson
system where the entangled $K_L$ state is pushed slightly in the direction of a
factorized constituent ($K_o$ or $\overline{K_o}$) as a consequence of the fact
that these can be distinguished via the sign of the charged lepton in a
semi-leptonic decay mode. The result is a CP violation that is within 20% of
the experimental value.
| [
{
"version": "v1",
"created": "Tue, 12 Nov 1996 02:57:41 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Fivel",
"Daniel I.",
""
]
] |
quant-ph/9611017 | Hideo Mabuchi | J. I. Cirac, P. Zoller, H. J. Kimble, and H. Mabuchi | Quantum state transfer and entanglement distribution among distant nodes
in a quantum network | 4 pages, 3 postscript figures | null | 10.1103/PhysRevLett.78.3221 | null | quant-ph | null | We propose a scheme to utilize photons for ideal quantum transmission between
atoms located at spatially-separated nodes of a quantum network. The
transmission protocol employs special laser pulses which excite an atom inside
an optical cavity at the sending node so that its state is mapped into a
time-symmetric photon wavepacket that will enter a cavity at the receiving node
and be absorbed by an atom there with unit probability. Implementation of our
scheme would enable reliable transfer or sharing of entanglement among
spatially distant atoms.
| [
{
"version": "v1",
"created": "Tue, 12 Nov 1996 19:15:50 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Cirac",
"J. I.",
""
],
[
"Zoller",
"P.",
""
],
[
"Kimble",
"H. J.",
""
],
[
"Mabuchi",
"H.",
""
]
] |
quant-ph/9611018 | Giuseppe Iannaccone | G. Iannaccone | Weak measurement and the traversal time problem | Talk given at the Adriatico Research Conference on ``Tunnelling and
its implications'', 30 July--2 August 1996, ICTP, Trieste | null | null | null | quant-ph | null | The theory of weak measurement, proposed by Aharonov and coworkers, has been
applied by Steinberg to the long-discussed traversal time problem. The
uncertainty and ambiguity that characterize this concept from the perspective
of von Neumann measurement theory apparently vanish, and joint probabilities
and conditional averages become meaningful concepts. We express the Larmor
clock and some other well-known methods in the weak measurement formalism. We
also propose a method to determine higher moments of the traversal time
distribution in terms of the outcome of a gedanken experiment, by introducing
an appropriate operator. Since the weak measurement approach can sometimes lead
to unphysical results, for example average negative reflection times and higher
moments, the interpretation of the results obtained remains an open problem.
| [
{
"version": "v1",
"created": "Wed, 13 Nov 1996 09:08:57 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Iannaccone",
"G.",
""
]
] |
quant-ph/9611019 | Boris F. Samsonov | Boris F. Samsonov | Time-dependent parasupersymmetry in quantum mechanics | 11pages, latex, amsfonts, no figures | Mod.Phys.Lett. A11 (1996) 2095-2104 | 10.1142/S0217732396002083 | null | quant-ph | null | Parasupersymmetry of the one dimensional time-dependent Schr\"odinger
equation is established. It is intimately connected with a chain of the
time-dependent Darboux transformations. As an example a parasupersymmetric
model of nonrelativistic free particle with threefold degenerate discrete
spectrum of an integral of motion is constructed.
| [
{
"version": "v1",
"created": "Wed, 13 Nov 1996 09:32:05 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Samsonov",
"Boris F.",
""
]
] |
quant-ph/9611020 | Dirk Sondermann | Almut Beige, Gerhard C. Hegerfeldt | Quantum Zeno Effect and Light-Dark Periods for a Single Atom | 16 pages, LaTeX, a4.sty; to appear in J. Phys. A | J.Phys.A30:1323-1334,1997 | 10.1088/0305-4470/30/4/031 | null | quant-ph | null | The quantum Zeno effect (QZE) predicts a slow-down of the time development of
a system under rapidly repeated ideal measurements, and experimentally this was
tested for an ensemble of atoms using short laser pulses for non-selective
state measurements. Here we consider such pulses for selective measurements on
a single system. Each probe pulse will cause a burst of fluorescence or no
fluorescence. If the probe pulses were strictly ideal measurements, the QZE
would predict periods of fluorescence bursts alternating with periods of no
fluorescence (light and dark periods) which would become longer and longer with
increasing frequency of the measurements. The non-ideal character of the
measurements is taken into account by incorporating the laser pulses in the
interaction, and this is used to determine the corrections to the ideal case.
In the limit, when the time between the laser pulses goes to zero, no freezing
occurs but instead we show convergence to the familiar macroscopic light and
dark periods of the continuously driven Dehmelt system. An experiment of this
type should be feasible for a single atom or ion in a trap
| [
{
"version": "v1",
"created": "Wed, 13 Nov 1996 17:53:37 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Beige",
"Almut",
""
],
[
"Hegerfeldt",
"Gerhard C.",
""
]
] |
quant-ph/9611021 | Tad Hogg | Tad Hogg and J. Geoffrey Chase | Quantum Smart Matter | 15 pages, Latex, 3 figures, this is an extended version of a paper to
appear at PhysComp96, further info available at
ftp://parcftp.xerox.com/pub/dynamics/quantum.html | Proc. of the Workshop on Physics and Computation (PhysComp96), pp.
147-152 (1996) | null | null | quant-ph cond-mat | null | The development of small-scale sensors and actuators enables the construction
of smart matter in which physical properties of materials are controlled in a
distributed manner. In this paper, we describe how quantum computers could
provide an additional capability, programmable control over some quantum
behaviors of such materials. This emphasizes the need for spatial coherence, in
contrast to the more commonly discussed issue of temporal coherence for quantum
computing. We also discuss some possible applications and engineering issues
involved in exploiting this possibility.
| [
{
"version": "v1",
"created": "Wed, 13 Nov 1996 19:48:12 GMT"
}
] | 2009-10-06T00:00:00 | [
[
"Hogg",
"Tad",
""
],
[
"Chase",
"J. Geoffrey",
""
]
] |
quant-ph/9611022 | John K. Breslin | J. K. Breslin (1), C. A. Holmes (2) and G. J. Milburn (1) ((1) Physics
Department, (2) Mathematics Department, University of Queensland) | Quantum signatures of chaos in the dynamics of a trapped ion | 9 pages, 9 Postscript figures, Revtex, submitted to Phys. Rev. A | null | 10.1103/PhysRevA.56.3022 | null | quant-ph | null | We show how a nonlinear chaotic system, the parametrically kicked nonlinear
oscillator, may be realised in the dynamics of a trapped, laser-cooled ion,
interacting with a sequence of standing wave pulses. Unlike the original
optical scheme [G.J.Milburn and C.A.Holmes, Phys. Rev A, 44, p4704, (1991)],
the trapped ion enables strongly quantum dynamics with minimal dissipation.
This should permit an experimental test of one of the quantum signatures of
chaos; irregular collapse and revival dynamics of the average vibrational
energy.
| [
{
"version": "v1",
"created": "Thu, 14 Nov 1996 06:32:47 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Breslin",
"J. K.",
""
],
[
"Holmes",
"C. A.",
""
],
[
"Milburn",
"G. J.",
""
]
] |
quant-ph/9611023 | Alexander S. Holevo | A.S.Holevo (Steklov Mathematical Institute) | The Capacity of Quantum Channel with General Signal States | 8 pages, Latex, no figures, to be published in IEEE Trans. Inform.
Theory | IEEE Trans.Info.Theor. 44 (1998) 269-273 | null | null | quant-ph | null | It is shown that the capacity of a classical-quantum channel with arbitrary
(possibly mixed) states equals to the maximum of the entropy bound with respect
to all apriori distributions. This completes the recent result of Hausladen,
Jozsa, Schumacher, Westmoreland and Wooters, who proved the equality for the
pure state channel.
| [
{
"version": "v1",
"created": "Thu, 14 Nov 1996 11:50:05 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Holevo",
"A. S.",
"",
"Steklov Mathematical Institute"
]
] |
quant-ph/9611024 | prof. Shmuel Nussinov | S. Nussinov | Realistic experiments for measuring the wave function of a single
particle | LaTeX, 19 pages, 1 epsfig | Found.Phys. 28 (1998) 865-880 | 10.1016/S0370-2693(97)01114-3 | TAUP 2392-96 | quant-ph | null | We suggest scattering experiments which implement the concept of ``protective
measurements'' allowing the measurement of the complete wave function even when
only one quantum system (rather than an ensemble) is available. Such scattering
experiments require massive, slow, projectiles with kinetic energies lower than
the first excitation of the system in question. The results of such experiments
can have a (probabilistic) distribution (as is the case when the Born
approximation for the scattering is valid) or be deterministic (in a
semi-classical limit).
| [
{
"version": "v1",
"created": "Thu, 14 Nov 1996 10:15:17 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Nussinov",
"S.",
""
]
] |
quant-ph/9611025 | Dorit Aharonov | Dorit Aharonov (Physics and computer science, Hebrew Univ.) and
Michael Ben-Or (Computer science, Hebrew univ.) | Fault Tolerant Quantum Computation with Constant Error | 18 pages, now includes bibliography | null | null | null | quant-ph | null | Recently Shor showed how to perform fault tolerant quantum computation when
the error probability is logarithmically small. We improve this bound and
describe fault tolerant quantum computation when the error probability is
smaller than some constant threshold. The cost is polylogarithmic in time and
space, and no measurements are used during the quantum computation. The result
holds also for quantum circuits which operate on nearest neighbors only. To
achieve this noise resistance, we use concatenated quantum error correcting
codes. The scheme presented is general, and works with all quantum codes that
satisfy some restrictions, namely that the code is ``proper''.
We present two explicit classes of proper quantum codes. The first example of
proper quantum codes generalizes classical secret sharing with polynomials. The
second uses a known class of quantum codes and converts it to a proper code.
This class is defined over a field with p elements, so the elementary quantum
particle is not a qubit but a ``qupit''. With our codes, the threshold is about
10^(-6). Hopefully, this paper motivates a search for proper quantum codes with
higher thresholds, at which point quantum computation becomes practical.
| [
{
"version": "v1",
"created": "Thu, 14 Nov 1996 11:44:10 GMT"
},
{
"version": "v2",
"created": "Fri, 15 Nov 1996 10:57:42 GMT"
}
] | 2008-02-03T00:00:00 | [
[
"Aharonov",
"Dorit",
"",
"Physics and computer science, Hebrew Univ."
],
[
"Ben-Or",
"Michael",
"",
"Computer science, Hebrew univ."
]
] |
quant-ph/9611026 | Mike Ashworth | M. C. Ashworth | Coherent State Approach to Time Reparameterization Invariant Systems | null | Phys.Rev. A57 (1998) 2357-2367 | 10.1103/PhysRevA.57.2357 | null | quant-ph gr-qc | null | For many years coherent states have been a useful tool for understanding
fundamental questions in quantum mechanics. Recently, there has been work on
developing a consistent way of including constraints into the phase space path
integral that naturally arises in coherent state quantization. This new
approach has many advantages over other approaches, including the lack of any
Gribov problems, the independence of gauge fixing, and the ability to handle
second-class constraints without any ambiguous determinants. In this paper, I
use this new approach to study some examples of time reparameterization
invariant systems, which are of special interest in the field of quantum
gravity.
| [
{
"version": "v1",
"created": "Thu, 14 Nov 1996 20:35:04 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Ashworth",
"M. C.",
""
]
] |
quant-ph/9611027 | Andrew Steane | Andrew Steane (Clarendon Laboratory, Oxford University) | Active stabilisation, quantum computation and quantum state synthesis | 8 pages LaTeX plus 4 figures. Submitted to Phys. Rev. Lett | Phys.Rev.Lett.78:2252-2255,1997 | 10.1103/PhysRevLett.78.2252 | null | quant-ph | null | Active stabilisation of a quantum system is the active suppression of noise
(such as decoherence) in the system, without disrupting its unitary evolution.
Quantum error correction suggests the possibility of achieving this, but only
if the recovery network can suppress more noise than it introduces. A general
method of constructing such networks is proposed, which gives a substantial
improvement over previous fault tolerant designs. The construction permits
quantum error correction to be understood as essentially quantum state
synthesis. An approximate analysis implies that algorithms involving very many
computational steps on a quantum computer can thus be made possible.
| [
{
"version": "v1",
"created": "Sat, 16 Nov 1996 14:49:19 GMT"
}
] | 2009-01-23T00:00:00 | [
[
"Steane",
"Andrew",
"",
"Clarendon Laboratory, Oxford University"
]
] |
quant-ph/9611028 | Dorit Aharonov | D. Aharonov (Physics and CS, Hebrew Univ.) and M. Ben-Or(CS,Hebrew
univ.) and R. Impagliazzo (CS, UCSD) and N. Nisan (CS, Hebrew univ.) | Limitations of Noisy Reversible Computation | 13 pages | null | null | null | quant-ph | null | Noisy computation and reversible computation have been studied separately,
and it is known that they are as powerful as unrestricted computation. We study
the case where both noise and reversibility are combined and show that the
combined model is weaker than unrestricted computation. In our noisy reversible
circuits, each wire is flipped with probability p each time step, and all the
inputs to the circuit are present in time 0. We prove that any noisy reversible
circuit must have size exponential in its depth in order to compute a function
with high probability. This is tight as we show that any circuit can be
converted into a noise-resistant reversible one with a blow up in size which is
exponential in the depth. This establishes that noisy reversible computation
has the power of the complexity class NC^1.
We extend this to quantum circuits(QC). We prove that any noisy QC which is
not worthless, and for which all inputs are present at time 0, must have size
exponential in its depth. (This high-lights the fact that fault tolerant QC
must use a constant supply of inputs all the time.) For the lower bound, we
show that quasi-polynomial noisy QC are at least powerful as logarithmic depth
QC, (or QNC^1). Making these bounds tight is left open in the quantum case.
| [
{
"version": "v1",
"created": "Sun, 17 Nov 1996 16:40:20 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Aharonov",
"D.",
"",
"Physics and CS, Hebrew Univ."
],
[
"Ben-Or",
"M.",
"",
"CS,Hebrew\n univ."
],
[
"Impagliazzo",
"R.",
"",
"CS, UCSD"
],
[
"Nisan",
"N.",
"",
"CS, Hebrew univ."
]
] |
quant-ph/9611029 | Dorit Aharonov | Dorit Aharonov (Physics and computer science, Hebrew Univ.) and
Michael Ben-Or (Computer science, Hebrew univ.) | Polynomial Simulations of Decohered Quantum Computers | 12 pages | null | null | null | quant-ph | null | We define formally decohered quantum computers (using density matrices), and
present a simulation of them by a probabalistic classical Turing Machine. We
study the slowdown of the simulation for two cases: (1) sequential quantum
computers, or quantum Turing machines(QTM), and (2) parallel quantum computers,
or quantum circuits. This paper shows that the computational power of decohered
quantum computers depends strongly on the amount of parallelism in the
computation.
The expected slowdown of the simulation of a QTM is polynomial in time and
space of the quantum computation, for any non zero decoherence rate. This means
that a QTM subjected to any amount of noise is worthless. For decohered quantum
circuits, the situation is more subtle and depends on the decoherence rate,
eta. We find that our simulation is efficient for circuits with decoherence
rate higher than some constant, but exponential for general circuits with
decoherence rate lower than some other constant. Using computer experiments, we
show that the transition from exponential cost to polynomial cost happens in a
short range of decoherence rates, and exhibit the phase transitions in various
quantum circuits.
| [
{
"version": "v1",
"created": "Sun, 17 Nov 1996 17:24:08 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Aharonov",
"Dorit",
"",
"Physics and computer science, Hebrew Univ."
],
[
"Ben-Or",
"Michael",
"",
"Computer science, Hebrew univ."
]
] |
quant-ph/9611030 | Wai-Yee Keung | Marina Hruska, Wai-Yee Keung, and Uday Sukhatme | Accuracy of Semiclassical Methods for Shape Invariant Potentials | 7 pages, Latex, and two tables in postscript | Phys.Rev.A55:3345-3350,1997 | 10.1103/PhysRevA.55.3345 | UICHEP-TH/96-18 | quant-ph | null | We study the accuracy of several alternative semiclassical methods by
computing analytically the energy levels for many large classes of exactly
solvable shape invariant potentials. For these potentials, the ground state
energies computed via the WKB method typically deviate from the exact results
by about 10%, a recently suggested modification using nonintegral Maslov
indices is substantially better, and the supersymmetric WKB quantization method
gives exact answers for all energy levels.
| [
{
"version": "v1",
"created": "Mon, 18 Nov 1996 16:44:55 GMT"
}
] | 2009-09-01T00:00:00 | [
[
"Hruska",
"Marina",
""
],
[
"Keung",
"Wai-Yee",
""
],
[
"Sukhatme",
"Uday",
""
]
] |
quant-ph/9611031 | Hoi-Kwong Lo | Hoi-Kwong Lo (HP Labs, Bristol and University of Santa Barbara) | Insecurity of Quantum Secure Computations | The discussion on the insecurity of even non-ideal protocols has been
greatly extended. Other technical points are also clarified. Version accepted
for publication in Phys. Rev. A | null | 10.1103/PhysRevA.56.1154 | null | quant-ph cs.CR | null | It had been widely claimed that quantum mechanics can protect private
information during public decision in for example the so-called two-party
secure computation. If this were the case, quantum smart-cards could prevent
fake teller machines from learning the PIN (Personal Identification Number)
from the customers' input. Although such optimism has been challenged by the
recent surprising discovery of the insecurity of the so-called quantum bit
commitment, the security of quantum two-party computation itself remains
unaddressed. Here I answer this question directly by showing that all
``one-sided'' two-party computations (which allow only one of the two parties
to learn the result) are necessarily insecure. As corollaries to my results,
quantum one-way oblivious password identification and the so-called quantum
one-out-of-two oblivious transfer are impossible. I also construct a class of
functions that cannot be computed securely in any ``two-sided'' two-party
computation. Nevertheless, quantum cryptography remains useful in key
distribution and can still provide partial security in ``quantum money''
proposed by Wiesner.
| [
{
"version": "v1",
"created": "Tue, 19 Nov 1996 10:08:47 GMT"
},
{
"version": "v2",
"created": "Mon, 28 Apr 1997 18:00:14 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Lo",
"Hoi-Kwong",
"",
"HP Labs, Bristol and University of Santa Barbara"
]
] |
quant-ph/9611032 | Chris Adami | N.J. Cerf and C. Adami (California Institute of Technology) | Accessible information in quantum measurement | 4 pages RevTeX with psfig, 3 figures | null | null | KRL MAP-207 | quant-ph | null | The amount of information that can be accessed via measurement of a quantum
system prepared in different states is limited by the Kholevo bound. We present
a simple proof of this theorem and its extension to sequential measurements
based on the properties of quantum conditional and mutual entropies. The proof
relies on a minimal physical model of the measurement which does not assume
environmental decoherence, and has an intuitive diagrammatic representation.
| [
{
"version": "v1",
"created": "Tue, 19 Nov 1996 22:58:01 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Cerf",
"N. J.",
"",
"California Institute of Technology"
],
[
"Adami",
"C.",
"",
"California Institute of Technology"
]
] |
quant-ph/9611033 | Howard M. Wiseman | Howard M. Wiseman (University of Queensland) | What is an atom laser? | 18 pages, LaTeX. No figures. Submitted to Phys. Rev. A on 19 November
1996 | null | null | null | quant-ph | null | An atom laser is a hypothetical device which would produce an atomic field
analogous to the electromagnetic field of a photon laser. Here I argue that for
this analogy to be meaningful it is necessary to have a precise definition of a
laser which applies equally to photon or atom lasers. The definition I propose
is based upon the principle that the output of a laser is well-approximated by
a classical wave of fixed intensity and phase. This principle yields four
quantitative conditions which the output of a device must satisfy in order for
that device to be considered a laser. While explaining these requirements, I
analyse the similarities and differences between atom and photon lasers. I show
how these conditions are satisfied first by an idealized photon laser model,
and then by a more generic model which can apply to atom lasers also. Lastly, I
briefly discuss the current proposals for atom lasers and whether they could be
true lasers.
| [
{
"version": "v1",
"created": "Wed, 20 Nov 1996 04:23:59 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Wiseman",
"Howard M.",
"",
"University of Queensland"
]
] |
quant-ph/9611034 | Matteo G. A. Paris | Matteo G. A. Paris, Alexei V. Chizhov, and Ole Steuernagel
(Arbeitsgruppe ``Nichtklassiche Strahlung'' der Max-Planck-Gesellschaft) | Phase Space Distributions from Three-Port Couplers | Three figures. To appear in Optics Comm | Opt.Commun.134:117,1997 | 10.1016/S0030-4018(96)00541-X | null | quant-ph | null | A wide class of phase space distributions of a single mode radiation field is
shown to be directly accessible to measurement by linear symmetric three-port
optical couplers.
| [
{
"version": "v1",
"created": "Wed, 20 Nov 1996 11:27:52 GMT"
}
] | 2009-10-30T00:00:00 | [
[
"Paris",
"Matteo G. A.",
"",
"Arbeitsgruppe ``Nichtklassiche Strahlung'' der Max-Planck-Gesellschaft"
],
[
"Chizhov",
"Alexei V.",
"",
"Arbeitsgruppe ``Nichtklassiche Strahlung'' der Max-Planck-Gesellschaft"
],
[
"Steuernagel",
"Ole",
"",
"Arbeitsgruppe ``Nichtklassiche Strahlung'' der Max-Planck-Gesellschaft"
]
] |
quant-ph/9611035 | Matteo G. A. Paris | Matteo G. A. Paris (Arbeitsgruppe Nichtklassiche Strahlung der
Max-Planck-Gesellschaft) | Interferometry as a binary decision problem | 9 pages. One picture in LaTeX. Epic and Eepic extension needed | null | 10.1016/S0375-9601(96)00862-6 | null | quant-ph | null | Binary decision theory has been applied to the general interferometric
problem. Optimal detection scheme-according to the Neyman-Pearson criterion-has
been considered for different phase-enhanced states of radiation field, and the
corresponding bounds on minimum detectable phase shift has been evaluated. A
general bound on interferometric precision has been also obtained in terms of
photon number fluctuations of the signal mode carrying the phase information.
| [
{
"version": "v1",
"created": "Thu, 21 Nov 1996 11:44:54 GMT"
}
] | 2016-09-08T00:00:00 | [
[
"Paris",
"Matteo G. A.",
"",
"Arbeitsgruppe Nichtklassiche Strahlung der\n Max-Planck-Gesellschaft"
]
] |
quant-ph/9611036 | Piotr Kochanski | Piotr Kochanski (Center for Theoretical Physics) and Krzysztof
Wodkiewicz (University of New Mexico) | Operational Theory of the Eight-Port Homodyne Detection | 18 pages, uses Revtex and epsfig.sty, 4 Encapsulated Postscript
figures, submitted to J. Mod. Opt | null | null | CFT PAN 11-1996 | quant-ph | null | The eight-port homodyne detection apparatus is analyzed in the framework of
the operational theory of quantum measurement. For an arbitrary quantum noise
leaking through the unused port of the beam splitter, the positive operator
valued measure and the corresponding operational homodyne observables are
derived. It is shown that such an eight-port homodyne device can be used to
construct the operational quantum trigonometry of an optical field. The quantum
trigonometry and the corresponding phase space Wigner functions are derived for
a signal field probed by a classical local oscillator and a squeezed vacuum in
the unused port.
| [
{
"version": "v1",
"created": "Thu, 21 Nov 1996 13:42:08 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Kochanski",
"Piotr",
"",
"Center for Theoretical Physics"
],
[
"Wodkiewicz",
"Krzysztof",
"",
"University of New Mexico"
]
] |
Subsets and Splits
No saved queries yet
Save your SQL queries to embed, download, and access them later. Queries will appear here once saved.