{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"122afb8197e640e6dff3c8bfe7b986af174295f151b5f99ec56e29a493b9dd4d","created":"2026-10-03T07:18:09Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"625fac0aef7cd234c80bbb00ec9b55b57ea0d70d42ed0f539a579743bb0ee484","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"qi.causal-order-qrf.quantum-time-dilation","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"A moving clock ticks slower by an amount fixed by its speed. If the clock is in a superposition of two speeds, theory predicts an extra effect that no ordinary random mixture of speeds can produce, and no measurement of it has been reported.","posed_since":"2020","precise":"For a clock of rest mass m with internal Hamiltonian $H_{\\mathrm{clock}}$ whose center of mass is in a coherent superposition of momenta, the mass-energy coupling $H = \\sqrt{p^{2} c^{2} + (m c^{2} + H_{\\mathrm{clock}})^{2}}$ gives a proper-time distribution that differs from that of the corresponding classical mixture of momenta by a coherence-dependent term (Smith and Ahmadi, Nature Communications 2020). Determine whether atomic or ion clocks can resolve this quantum contribution, the momentum separation and fractional frequency resolution required, and measure it.","problem_ref":null,"references":"","settled_by":"A clock comparison in which a momentum-superposed clock and a matched classical mixture show the predicted difference in frequency shift.","status_note":"Predicted in 2020 (doi:10.1038/s41467-020-18264-4); no measurement was found in the sources checked.","title":"Measure quantum time dilation of a clock in a momentum superposition","topic_ref":"0d56bf5e6184723e4f024030c3c79a9dde6f6fca1514c152e520bdf56cfb78be"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"acc06921666a1c4fa23f261a8d062b53ee0ccbf8ffca1503c9684f6704c3c14f","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"047611e42b261a7210394e1bb6c4ca1a596a031a1a70db29f23218c27ab46980","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"3RTy8gVFjVywq64iG4X3pQOdQL4t2n_Bk2AzhfL870VGVxOyC1ImOEBITGf284mnXQ1yOGwTYG278rPEzE0hDg"},"schema":"pubphys.envelope/1"},"record_hash":"acc06921666a1c4fa23f261a8d062b53ee0ccbf8ffca1503c9684f6704c3c14f","leaf_index":1967}