BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Ramis Movassagh (MIT-IBM) DTSTART:20210217T170000Z DTEND:20210217T180000Z DTSTAMP:20260423T041819Z UID:UKYhepth/29 DESCRIPTION:Title: Constructing quantum codes from any classical code and their embedding i n ground space of local Hamiltonians\nby Ramis Movassagh (MIT-IBM) as part of Theoretical Physics Seminars (Kentucky)\n\n\nAbstract\nWe introduc e a framework for constructing a quantum error correcting code from any cl assical error correcting code. This includes CSS codes and goes beyond the stabilizer formalism to allow quantum codes to be constructed from classi cal codes that are not necessarily linear or self-orthogonal. We give an a lgorithm that explicitly constructs quantum codes with linear distance and constant rate from classical codes with a linear distance and rate. As il lustrations for small size codes\, we obtain Steane's 7−qubit code uniqu ely from Hamming's [7\,4\,3] code\, and obtain other error detecting quant um codes from other explicit classical codes of length 4 and 6. Motivated by quantum LDPC codes and the use of physics to protect quantum informatio n\, we introduce a new 2-local frustration free quantum spin chain Hamilto nian whose ground space we analytically characterize completely. By mappin g classical codewords to basis states of the ground space\, we utilize our framework to demonstrate that the ground space contains explicit quantum codes with linear distance. This side-steps the Bravyi-Terhal no-go theore m because our work allows for more general quantum codes beyond the stabil izer and/or linear codes. We hesitate to call this an example of {\\it sub space} quantum LDPC code with linear distance.\n LOCATION:https://researchseminars.org/talk/UKYhepth/29/ END:VEVENT END:VCALENDAR