{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.topic/1","content_sha256":"8ae28177b90b104b55c9a94457dfd31853a7104d0127a0a5d529cd459e5a721a","created":"2026-10-03T07:17:52Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":[],"salt":"484f42e862d0421c484371618034f83cdb475959dbfbbfc36b1fd4e8f10ca099","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"topic"},"content":{"external_id":"qft.string-nonperturbative","field":"qft","n":"1","review_cite":"T. Banks, W. Fischler, S. H. Shenker, L. Susskind, M theory as a matrix model: A conjecture, Phys. Rev. D 55, 5112, 1997","review_link":"https://arxiv.org/abs/hep-th/9610043","review_verified":"true","summary":"String theory is defined mostly as a series of approximations around a fixed spacetime, and M-theory, its eleven-dimensional limit, has no general definition. Exact definitions exist only in special cases, such as spaces with negative vacuum energy.","title":"Nonperturbative definition of string and M-theory","topic_ref":null,"why":"A theory of quantum gravity needs a definition that works in any spacetime, including our expanding universe."},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"77b6787c01ad201a13194ef87168eea66a0756da2a9a351dc5d7a1594827efd5","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"7e4938b18d58b02c60e50e1eaabbfee7bc54e95b14a5dda70376e62a8abb16a3","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"77d6MFnLL1bgeTq4GwOYAXsqQoNxuLcK61vDMOfA7QNdQu3vHtbg_ZRrzLVofv1ZJyFRWo62RtHYt0RGNj_fAQ"},"schema":"pubphys.envelope/1"},"record_hash":"77b6787c01ad201a13194ef87168eea66a0756da2a9a351dc5d7a1594827efd5","leaf_index":325}