{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"bda3629a6d1fce7801c39e2b0d684e319396986a5a11d67e57ac67fe96cb14a3","created":"2026-10-03T07:18:10Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"3628aa67bb87216011b09f9134fe545788fd30ee49274232b7e116c7f23bb675","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"mechanism","assisted_by":[],"external_id":"qi.tunneling-arrival-time.tunneling-duration","kind":"phenomenon","literature_status":"contested","n":"1","parents":[],"plain":"A particle can cross a barrier it classically could not climb, but the time spent inside has several definitions (phase delay, dwell time, Larmor time) that give different numbers, some implying faster-than-light motion. The question is which, if any, is the physical duration.","posed_since":"1932","precise":"For a particle of energy $E<V_0$ incident on a barrier of width $L$, compare the Wigner phase delay, dwell time, Buttiker-Landauer traversal time and weak-value Larmor times $\\tau_y,\\tau_z$. Determine whether a single operationally defined traversal time exists (e.g. the reading of a weakly coupled internal clock conditioned on transmission) and how it scales with $L$.","problem_ref":null,"references":"","settled_by":"A theory of clocks coupled to the tunneling particle whose predictions agree with Larmor-clock, attoclock and Ramsey-clock experiments.","status_note":"A 2024 analysis proposed a unified treatment via Ramsey clocks (arXiv:2404.14382); attoclock and Larmor results are still interpreted differently in 2025 (arXiv:2503.07859).","title":"How long does a particle spend inside a tunneling barrier?","topic_ref":"358768349f8fe9b49e5942c4fef2bbf2a089805f474e2a5f2d52d216a641711f"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"c98bc365982ccf041c16ecefa2e9bbcf3c1ba198726ef75107771a435bdeb2b8","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"3e78c35e6055c06141164fd8f477ff9c7dd59e37b2e6cbbf84de9634b01304c8","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"kIOyJyDTVFcVBe4Z3XXKWcYF_t1Qo2bPDU5TNfJFOwdrOA6CI8E8T1x1L0KkToCbhCvKInZ4jPa8IMCfuVevCg"},"schema":"pubphys.envelope/1"},"record_hash":"c98bc365982ccf041c16ecefa2e9bbcf3c1ba198726ef75107771a435bdeb2b8","leaf_index":2058}