{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"2de07f63659f6d6dc78562644f232fa7ba8537a2afc69830c2dd484a2272cead","created":"2026-10-03T07:17:59Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"4fb49d9d8e749acb9254767ff34e9422e1ce06c2417e2f4d0468881d9b304466","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"cm.dqpt.mixed-state-generalization","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"The theory is built for pure starting states at zero temperature. For warm starting states several competing definitions exist, and they disagree on whether the sharp kinks remain.","posed_since":"","precise":"For an initial Gibbs state $\\rho_0 = \\exp(-\\beta H_i)/Z$, compare generalized Loschmidt echoes (the interferometric echo $\\operatorname{tr}(\\rho_0 U(t))$ and fidelity-based echoes) in interacting models. Does any measurable generalization show nonanalyticities at finite $\\beta$ that connect continuously to the pure-state transitions as $\\beta \\to \\infty$? Answer yes or no, with the definition.","problem_ref":null,"references":"","settled_by":"Exact free-fermion results extended to interacting chains by numerics, together with a measurement protocol.","status_note":"","title":"Do dynamical quantum phase transitions survive at finite temperature","topic_ref":"f0f2c6f7bdd6262d6700dc8806ab5f70f58e1999b1e12bad11c2bf274d3c1f12"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"8ec996e190dc8327e1f09d05dbbcac0e8a9dfeb89b68d92c761b63e1275b27f0","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"ad87e1d7917f7dabee2c3e225a003793e34c44431aa851ce5ef30cecae96904f","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"-qHSdOQQxH6GyhUzAHt7q_8VeilKoz3YXqzZzrjSjlX71vWIjbR1_tamguwTF8Ew6AjcfM6Ob3pzwyEYJkiPCQ"},"schema":"pubphys.envelope/1"},"record_hash":"8ec996e190dc8327e1f09d05dbbcac0e8a9dfeb89b68d92c761b63e1275b27f0","leaf_index":954}