{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.topic/1","content_sha256":"d016a2f12718188937e8677c9e8323eb08f3bdd592641dd22768ed50342c16fe","created":"2026-10-03T07:17:53Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":[],"salt":"d8008e2302aef2102329a12c81cadb06c0859df44d9e0d353a6495baa40b1b99","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"topic"},"content":{"external_id":"qi.tunneling-arrival-time","field":"qi","n":"1","review_cite":"Ramos, Spierings, Racicot, Steinberg, Measurement of the time spent by a tunnelling atom within the barrier region, Nature, 2020","review_link":"https://doi.org/10.1038/s41586-020-2490-7","review_verified":"true","summary":"Quantum mechanics has no standard clock observable, so questions such as how long a particle takes to tunnel through a barrier, or when it reaches a detector, have several competing answers. Experiments with cold atoms and ultrafast lasers now measure these times.","title":"Time in quantum mechanics: tunneling, arrival, clocks","topic_ref":null,"why":"Time enters quantum theory as an external parameter, and these problems test whether durations of quantum processes are well defined."},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"358768349f8fe9b49e5942c4fef2bbf2a089805f474e2a5f2d52d216a641711f","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"b24191481df8420913c1dbea54e24ec833508de2308f089f734398aeddd56860","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"sxI0Io5d0UMCeSFrEZGp2YzahUvadHGYtMXXGXZgA30h-q0z-vRghNkXW8UEhgGHjLJjyxOFUa2uzwtABBGnDQ"},"schema":"pubphys.envelope/1"},"record_hash":"358768349f8fe9b49e5942c4fef2bbf2a089805f474e2a5f2d52d216a641711f","leaf_index":347}