{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"db22b316194ffeaabbca3fed114b93c8827c93e2c6cdec40c7db4c2e1fab472b","created":"2026-10-03T07:18:07Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"43da46b38527ac60f1db625dfbeac9e4085edb5e4db2dafcc59a7383aa667013","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"nuc.qcd-phase-diagram.critical-point","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"At zero net baryon density, ordinary matter turns into quark-gluon plasma smoothly as it heats. At higher density the change may become abrupt, and the critical point is where smooth turns abrupt, if it exists.","posed_since":"1989","precise":"Determine whether the chiral crossover line $T_{\\mathrm{pc}}(\\mu_B)$ ($T_{\\mathrm{pc}}(0)$ about $156\\,\\mathrm{MeV}$, $\\mu_B$ the baryon chemical potential) ends at a critical point (T_c, mu_B,c) beyond which the transition is first order, and locate it. Lattice QCD disfavors a critical point at $\\mu_B/T$ below about 3. Answer: yes or no, and (T_c, mu_B,c) with uncertainty.","problem_ref":null,"references":"","settled_by":"A first-principles calculation reaching $\\mu_B/T > 3$, or an experimentally established nonmonotonic fluctuation signal reproduced by dynamical critical-point modeling.","status_note":"Functional-method and lattice-based extrapolations from 2021 to 2025 placed a possible critical point near $\\mu_B$ of roughly 400 to 650 MeV, beyond direct lattice reach as of 2026.","title":"Existence and location of the QCD critical point","topic_ref":"8cebfc31c6dfbbabf0b4214c4b9557e92e9b9f0d637fcd43a3fcc8c806d62935"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"59c70c58ebc1de8bff7fc3398a95a4795b7d421f35be6bf7283b56f00e4e3db6","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"2d63cb8ff101d2f0465155f97615c8f20c9d736fff9cf513e092e88e3cc73fea","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"iUz1tqhZ6CoZ2SvLZ_Db3VKOAQ9fAXKHmfcq7ado_qR6Y8cjIpSTiZ6UcCQsPLpMBiFzyhvuitETnChIUNBBAg"},"schema":"pubphys.envelope/1"},"record_hash":"59c70c58ebc1de8bff7fc3398a95a4795b7d421f35be6bf7283b56f00e4e3db6","leaf_index":1799}