{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2013:LQDU7S2CQ37H3NJZOTE4I3IIEI","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"06e3af759fe57ffaf83fd4cf3a436a638743df82c9f52fd0863d18db13904fd8","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2013-04-28T14:11:53Z","title_canon_sha256":"f39be7b458fe5c426bf3e99cb760f66168bf525a592eb4ddb12a4c55e40024ec"},"schema_version":"1.0","source":{"id":"1304.7469","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1304.7469","created_at":"2026-05-18T03:08:14Z"},{"alias_kind":"arxiv_version","alias_value":"1304.7469v2","created_at":"2026-05-18T03:08:14Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1304.7469","created_at":"2026-05-18T03:08:14Z"},{"alias_kind":"pith_short_12","alias_value":"LQDU7S2CQ37H","created_at":"2026-05-18T12:27:51Z"},{"alias_kind":"pith_short_16","alias_value":"LQDU7S2CQ37H3NJZ","created_at":"2026-05-18T12:27:51Z"},{"alias_kind":"pith_short_8","alias_value":"LQDU7S2C","created_at":"2026-05-18T12:27:51Z"}],"graph_snapshots":[{"event_id":"sha256:5e7d2df1819f22aeb230b332356659dcf6b610c241ebf1f53755b658625af1ee","target":"graph","created_at":"2026-05-18T03:08:14Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"Quantum mechanics does not provide a clear answer to the question: What was the past of a photon which went through an interferometer? Various welcher weg measurements, delayed-choice which-path experiments and weak-measurements of photons in interferometers presented the past of a photon as a trajectory or a set of trajectories. We have carried out experimental weak measurements of the paths of photons going through a nested Mach-Zehnder interferometer which show a different picture: the past of a photon is not a set of continuous trajectories. The photons tell us that they have been in the p","authors_text":"Ariel Danan, Demitry Farfurnik, Lev Vaidman, Shimshon Bar-Ad","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2013-04-28T14:11:53Z","title":"Asking photons where have they been"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1304.7469","kind":"arxiv","version":2},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:f4b1588a87ef29c69d3721e5c07041ee4ced3c6d3c324b345c3bcf58f3111c04","target":"record","created_at":"2026-05-18T03:08:14Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"06e3af759fe57ffaf83fd4cf3a436a638743df82c9f52fd0863d18db13904fd8","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2013-04-28T14:11:53Z","title_canon_sha256":"f39be7b458fe5c426bf3e99cb760f66168bf525a592eb4ddb12a4c55e40024ec"},"schema_version":"1.0","source":{"id":"1304.7469","kind":"arxiv","version":2}},"canonical_sha256":"5c074fcb4286fe7db53974c9c46d08221f70e45882b75ef5021caafaae8cda9e","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"5c074fcb4286fe7db53974c9c46d08221f70e45882b75ef5021caafaae8cda9e","first_computed_at":"2026-05-18T03:08:14.006538Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T03:08:14.006538Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"L8s4GnM9zYDj++DDxATGwp1QlOEkC0AhJrN4DU/CxgBkYnwzxbrjNw0Z+cdjjZ0X14YPbQAkR6YvM3b7X0N0Cg==","signature_status":"signed_v1","signed_at":"2026-05-18T03:08:14.007589Z","signed_message":"canonical_sha256_bytes"},"source_id":"1304.7469","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:f4b1588a87ef29c69d3721e5c07041ee4ced3c6d3c324b345c3bcf58f3111c04","sha256:5e7d2df1819f22aeb230b332356659dcf6b610c241ebf1f53755b658625af1ee"],"state_sha256":"5eecb90c90d91c2dddcb87ea6df1612a3a8c0613a8367e6399be12878696273f"}