{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"3a58c99d3e31edcde18c1242474b539a0082405c437f0d741ce043516e41d86d","created":"2026-10-03T07:18:10Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"34432cbb7f56566a14c82e7207b33eab49507349f46182de413192b043392009","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"qi.quantum-thermo.engine-quantum-advantage","kind":"well-posed","literature_status":"contested","n":"1","parents":[],"plain":"Engines made of a few atoms can use superposition or entanglement in their working parts. Whether this gives more power at the same efficiency than any classical engine with the same parts is disputed.","posed_since":"","precise":"For heat engines with a $d$-level working medium coupled to baths at $T_h > T_c$, compare the maximal power $P$ at fixed efficiency $\\eta$ (or the efficiency at maximum power) of coherent quantum cycles with the best stochastic classical engine having the same level structure, bath couplings and control constraints. Determine whether $P_{quantum} > P_{classical}$ strictly, and identify the resource responsible.","problem_ref":null,"references":"","settled_by":"A proof of strict separation, or of its absence, under matched constraints, confirmed in a trapped-ion or superconducting engine.","status_note":"","title":"Do quantum effects let heat engines outperform classical ones?","topic_ref":"742b38754a9f76dd32b7efe7d343f52ad880f5cd0826c1581b9a9198dd522611"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"8ff2ff248548df53703d5cf004246a046e330d890c46c0980b6a8e68cf9935c0","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"612a55a816c5ad6174f244cdb1dd0cbe5a737a1e2bdfe945c9dbf3f434edac08","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"t6P7RvN5MjsFnDZJbfAX1M92RAtQ2-CzwTQ7tC3B2iRKc0bX9T7Gdu3NKsNPWVoScIsKLXPNmrNVEev4JHWFCA"},"schema":"pubphys.envelope/1"},"record_hash":"8ff2ff248548df53703d5cf004246a046e330d890c46c0980b6a8e68cf9935c0","leaf_index":2042}