{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"d557483f9fdc97aa6ba9a3ac54a273a4915a3f66ed2bd67183133d4153db5609","created":"2026-10-03T07:18:10Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"0d762f88c19225af18bcc3b0d5e3c42eea03abaefbee03c764e703b4e79cb43e","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"qi.quantum-thermo.cooling-time-third-law","kind":"well-posed","literature_status":"partially-resolved","n":"1","parents":[],"plain":"The third law says absolute zero cannot be reached in a finite number of steps. The open question is how fast the temperature can fall, given limited time or equipment, for the best possible refrigerator.","posed_since":"2017","precise":"For a finite system cooled within time t by a refrigerator of bounded size and Hamiltonian norm, determine the optimal scaling of the final temperature T(t) or ground-state infidelity with t and with resource measures (energy, bath dimension, control complexity), improving the lower bound of Masanes and Oppenheim (Nature Communications 2017) and the Landauer-versus-Nernst cost analysis (Taranto et al., 2023).","problem_ref":null,"references":"","settled_by":"Matching upper and lower bounds on T(t) achieved by an explicit protocol.","status_note":"Lower bounds on cooling time exist since 2017; tight scaling under realistic resource accounting is not established.","title":"Minimal time to cool a quantum system near absolute zero","topic_ref":"742b38754a9f76dd32b7efe7d343f52ad880f5cd0826c1581b9a9198dd522611"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"29ab3dfbb9f621d9ed7371a263f8c57d28a5c850d852c230ad8766c7741c9bb4","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"536c617133ee537af5813e414589a388e76d6c393ef9dfb42756a295ccc94529","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"6Sl7_hQ7OAmJE3-lWUM1YPYboGqaJEpL8ce3fOhf0JrBCVgUQ2mgP1MxtLGGHOagXIOY6AMCcTGTpWbTcSHtAQ"},"schema":"pubphys.envelope/1"},"record_hash":"29ab3dfbb9f621d9ed7371a263f8c57d28a5c850d852c230ad8766c7741c9bb4","leaf_index":2041}