{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2011:FCJ4CWSZVYA43TSSGRAAPNBWCK","short_pith_number":"pith:FCJ4CWSZ","canonical_record":{"source":{"id":"1102.2006","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.pop-ph","submitted_at":"2011-02-09T23:23:01Z","cross_cats_sorted":["physics.ed-ph","physics.ins-det"],"title_canon_sha256":"bd46269fca6c8ceb5ddbb4e20a2943167c66bf39bfd5ff824366f37211c64632","abstract_canon_sha256":"7f5139c57a47abfa5a4ea6f5e92a862eed9edfd21561f986b1de6d077013c788"},"schema_version":"1.0"},"canonical_sha256":"2893c15a59ae01cdce52344007b43612a456a47af804ab303a5b453a76deb4da","source":{"kind":"arxiv","id":"1102.2006","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1102.2006","created_at":"2026-05-18T04:19:02Z"},{"alias_kind":"arxiv_version","alias_value":"1102.2006v1","created_at":"2026-05-18T04:19:02Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1102.2006","created_at":"2026-05-18T04:19:02Z"},{"alias_kind":"pith_short_12","alias_value":"FCJ4CWSZVYA4","created_at":"2026-05-18T12:26:28Z"},{"alias_kind":"pith_short_16","alias_value":"FCJ4CWSZVYA43TSS","created_at":"2026-05-18T12:26:28Z"},{"alias_kind":"pith_short_8","alias_value":"FCJ4CWSZ","created_at":"2026-05-18T12:26:28Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2011:FCJ4CWSZVYA43TSSGRAAPNBWCK","target":"record","payload":{"canonical_record":{"source":{"id":"1102.2006","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.pop-ph","submitted_at":"2011-02-09T23:23:01Z","cross_cats_sorted":["physics.ed-ph","physics.ins-det"],"title_canon_sha256":"bd46269fca6c8ceb5ddbb4e20a2943167c66bf39bfd5ff824366f37211c64632","abstract_canon_sha256":"7f5139c57a47abfa5a4ea6f5e92a862eed9edfd21561f986b1de6d077013c788"},"schema_version":"1.0"},"canonical_sha256":"2893c15a59ae01cdce52344007b43612a456a47af804ab303a5b453a76deb4da","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T04:19:02.160475Z","signature_b64":"7UXQoYZ22G3CRxmw8vA/wQu9GNHsWZdsuLy7XXtvyCqpJOSTGy57Vx2xcWaHjFZsxucvz10ER6+7HJ6WM+i9DA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"2893c15a59ae01cdce52344007b43612a456a47af804ab303a5b453a76deb4da","last_reissued_at":"2026-05-18T04:19:02.159909Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T04:19:02.159909Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1102.2006","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T04:19:02Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"Z6LpGnwzgViI1Ro1DzQlbX/mwpOZIzdMCjDknp4SfduWxiKqnZ5/c6YGhrA75glyBdBuacsH1l5QCjOcWejtDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-03T10:35:20.082100Z"},"content_sha256":"b5670f0e75ddd2d0741d73264d40ed5c41fa24dd2fbf95343c963012b8f9a19d","schema_version":"1.0","event_id":"sha256:b5670f0e75ddd2d0741d73264d40ed5c41fa24dd2fbf95343c963012b8f9a19d"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2011:FCJ4CWSZVYA43TSSGRAAPNBWCK","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"High resolution stopwatch for cents","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["physics.ed-ph","physics.ins-det"],"primary_cat":"physics.pop-ph","authors_text":"Katalin Kopasz, Zoltan gingl","submitted_at":"2011-02-09T23:23:01Z","abstract_excerpt":"A very low-cost, easy-to-make stopwatch is presented to support various experiments in mechanics. The high-resolution stopwatch is based on two photodetectors connected directly to the microphone input of the sound card. A dedicated free open-source software has been developed and made available to download. The efficiency is demonstrated by a free fall experiment."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1102.2006","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T04:19:02Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"C0lchTaYA7DxMJPMwgHQssRLFzGiSUaIIKNzSeO2O+xqeCLQjXo+MNOHV+dnsq3l4L9UjLoe3Mqs1F4VCwwpBQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-03T10:35:20.082473Z"},"content_sha256":"05ae164c4d86ccbabe4dcff59c8ed172bd519b9d765377a5a0cb028a054c3dec","schema_version":"1.0","event_id":"sha256:05ae164c4d86ccbabe4dcff59c8ed172bd519b9d765377a5a0cb028a054c3dec"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/FCJ4CWSZVYA43TSSGRAAPNBWCK/bundle.json","state_url":"https://pith.science/pith/FCJ4CWSZVYA43TSSGRAAPNBWCK/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/FCJ4CWSZVYA43TSSGRAAPNBWCK/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-06-03T10:35:20Z","links":{"resolver":"https://pith.science/pith/FCJ4CWSZVYA43TSSGRAAPNBWCK","bundle":"https://pith.science/pith/FCJ4CWSZVYA43TSSGRAAPNBWCK/bundle.json","state":"https://pith.science/pith/FCJ4CWSZVYA43TSSGRAAPNBWCK/state.json","well_known_bundle":"https://pith.science/.well-known/pith/FCJ4CWSZVYA43TSSGRAAPNBWCK/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2011:FCJ4CWSZVYA43TSSGRAAPNBWCK","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":"7f5139c57a47abfa5a4ea6f5e92a862eed9edfd21561f986b1de6d077013c788","cross_cats_sorted":["physics.ed-ph","physics.ins-det"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.pop-ph","submitted_at":"2011-02-09T23:23:01Z","title_canon_sha256":"bd46269fca6c8ceb5ddbb4e20a2943167c66bf39bfd5ff824366f37211c64632"},"schema_version":"1.0","source":{"id":"1102.2006","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1102.2006","created_at":"2026-05-18T04:19:02Z"},{"alias_kind":"arxiv_version","alias_value":"1102.2006v1","created_at":"2026-05-18T04:19:02Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1102.2006","created_at":"2026-05-18T04:19:02Z"},{"alias_kind":"pith_short_12","alias_value":"FCJ4CWSZVYA4","created_at":"2026-05-18T12:26:28Z"},{"alias_kind":"pith_short_16","alias_value":"FCJ4CWSZVYA43TSS","created_at":"2026-05-18T12:26:28Z"},{"alias_kind":"pith_short_8","alias_value":"FCJ4CWSZ","created_at":"2026-05-18T12:26:28Z"}],"graph_snapshots":[{"event_id":"sha256:05ae164c4d86ccbabe4dcff59c8ed172bd519b9d765377a5a0cb028a054c3dec","target":"graph","created_at":"2026-05-18T04:19:02Z","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":"A very low-cost, easy-to-make stopwatch is presented to support various experiments in mechanics. The high-resolution stopwatch is based on two photodetectors connected directly to the microphone input of the sound card. A dedicated free open-source software has been developed and made available to download. The efficiency is demonstrated by a free fall experiment.","authors_text":"Katalin Kopasz, Zoltan gingl","cross_cats":["physics.ed-ph","physics.ins-det"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.pop-ph","submitted_at":"2011-02-09T23:23:01Z","title":"High resolution stopwatch for cents"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1102.2006","kind":"arxiv","version":1},"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:b5670f0e75ddd2d0741d73264d40ed5c41fa24dd2fbf95343c963012b8f9a19d","target":"record","created_at":"2026-05-18T04:19:02Z","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":"7f5139c57a47abfa5a4ea6f5e92a862eed9edfd21561f986b1de6d077013c788","cross_cats_sorted":["physics.ed-ph","physics.ins-det"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.pop-ph","submitted_at":"2011-02-09T23:23:01Z","title_canon_sha256":"bd46269fca6c8ceb5ddbb4e20a2943167c66bf39bfd5ff824366f37211c64632"},"schema_version":"1.0","source":{"id":"1102.2006","kind":"arxiv","version":1}},"canonical_sha256":"2893c15a59ae01cdce52344007b43612a456a47af804ab303a5b453a76deb4da","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"2893c15a59ae01cdce52344007b43612a456a47af804ab303a5b453a76deb4da","first_computed_at":"2026-05-18T04:19:02.159909Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T04:19:02.159909Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"7UXQoYZ22G3CRxmw8vA/wQu9GNHsWZdsuLy7XXtvyCqpJOSTGy57Vx2xcWaHjFZsxucvz10ER6+7HJ6WM+i9DA==","signature_status":"signed_v1","signed_at":"2026-05-18T04:19:02.160475Z","signed_message":"canonical_sha256_bytes"},"source_id":"1102.2006","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:b5670f0e75ddd2d0741d73264d40ed5c41fa24dd2fbf95343c963012b8f9a19d","sha256:05ae164c4d86ccbabe4dcff59c8ed172bd519b9d765377a5a0cb028a054c3dec"],"state_sha256":"ba0852bd2c6212d8abd1907952ffe78414c5994dacfb7ba21c9d56df55a05f23"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"zB37o+WXly9vVpHeccltuwGsjgVfoL7TJ7fGLihinYIK9KheZN7mKT/PG7rfcWn5T6BclLbwbUQeC5elkdqTCg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-03T10:35:20.084466Z","bundle_sha256":"5e0ece1a302d0b9078fbe8d4161f6262d352d466b8681a022eb16d4d273d7b65"}}