{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.topic/1","content_sha256":"bfe387b3dcdfc69a2b9e55555a6313b6f1017ac5af42232a19bace0d1835c641","created":"2026-10-03T07:17:51Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":[],"salt":"ecc537e5af160dd50113fc84d0837e0d0c3fa7b3cd1c0fab332c4b2b83bc6d20","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"topic"},"content":{"external_id":"cm.sign-problem-numerics","field":"cm","n":"1","review_cite":"M. Troyer, U.-J. Wiese, Computational Complexity and Fundamental Limitations to Fermionic Quantum Monte Carlo Simulations, Physical Review Letters, 2005","review_link":"https://doi.org/10.1103/PhysRevLett.94.170201","review_verified":"true","summary":"Computer simulations of many interacting electrons often require adding huge numbers of positive and negative terms that nearly cancel, so errors grow exponentially with system size; this is the sign problem. It is why different methods disagree on basic questions about two-dimensional electron models.","title":"Fermion sign problem and controlled many-body numerics","topic_ref":null,"why":"Controlled computation of interacting electrons would settle questions from high-temperature superconductivity to dense nuclear matter."},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"91e71237aaab9c02133089fdeea13d2a6f819a14e160de99c6f929cdb211535a","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"6a8e3a3e7cf2bbad62cba4e77a85d529e5553ffac3855eb846a682f7d77cc035","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"yUdatFzKL7uPTXXBhdztdntR7iezpGvcgYGNyEM8_PbW_nlTRuS0T2WWEMn9z7b1jHv2VLHtrMBwHg2AyX9RBA"},"schema":"pubphys.envelope/1"},"record_hash":"91e71237aaab9c02133089fdeea13d2a6f819a14e160de99c6f929cdb211535a","leaf_index":168}