text:   severely restricted",4,"['New paper! To build a good quantum computer, we need to encode information so that it can be processed without getting corrupted. We found that certain codes inspired by quantum gravity only allow very limited kinds of fault-tolerant processing.\n💻⚛️🤔\n<LINK>\n1/4 <LINK>', 'Context: theorists have been using holographic codes as toy models of quantum gravity for the last few years. They do a decent job at protecting information from errors/environmental noise, but their usefulness for fault-tolerant quantum computing is unclear.\n2/4', 'Our contribution: The kinds of fault-tolerant operations you can do most easily in holographic codes are very restricted - you can\'t implement non-Clifford gates, which are often the ""magic ingredient"" in universal fault-tolerant quantum computation strategies.\n3/4', ""So holographic codes might yet find a practical application for quantum computing, but we've ruled out the most straightforward way we might have hoped for.\n4/4\n\nThanks to coauthors, @DomJWilliamson, @KfirDolev\nand Vlad Calvera\n#quantph #quantum #scicomm #sciencetwitter #arxiv""]",21,03,1075