{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2020:4CQ4IMUVSWNEYLIHMUYLOBG347","short_pith_number":"pith:4CQ4IMUV","canonical_record":{"source":{"id":"2003.10509","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.bio-ph","submitted_at":"2020-03-23T19:38:14Z","cross_cats_sorted":["cond-mat.soft","q-bio.PE"],"title_canon_sha256":"e648f4ee10355ca64df6ea198fd8882b55276e1a81f60abbe15d8d8c46a3bfc3","abstract_canon_sha256":"5a3cd68996f378cfea88861e01c781d190c0bfe35d88181b5cbd1f6ae318dc8a"},"schema_version":"1.0"},"canonical_sha256":"e0a1c43295959a4c2d076530b704dbe7c32648fa69de21fde01b935081c63ccc","source":{"kind":"arxiv","id":"2003.10509","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2003.10509","created_at":"2026-07-05T05:04:08Z"},{"alias_kind":"arxiv_version","alias_value":"2003.10509v2","created_at":"2026-07-05T05:04:08Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2003.10509","created_at":"2026-07-05T05:04:08Z"},{"alias_kind":"pith_short_12","alias_value":"4CQ4IMUVSWNE","created_at":"2026-07-05T05:04:08Z"},{"alias_kind":"pith_short_16","alias_value":"4CQ4IMUVSWNEYLIH","created_at":"2026-07-05T05:04:08Z"},{"alias_kind":"pith_short_8","alias_value":"4CQ4IMUV","created_at":"2026-07-05T05:04:08Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2020:4CQ4IMUVSWNEYLIHMUYLOBG347","target":"record","payload":{"canonical_record":{"source":{"id":"2003.10509","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.bio-ph","submitted_at":"2020-03-23T19:38:14Z","cross_cats_sorted":["cond-mat.soft","q-bio.PE"],"title_canon_sha256":"e648f4ee10355ca64df6ea198fd8882b55276e1a81f60abbe15d8d8c46a3bfc3","abstract_canon_sha256":"5a3cd68996f378cfea88861e01c781d190c0bfe35d88181b5cbd1f6ae318dc8a"},"schema_version":"1.0"},"canonical_sha256":"e0a1c43295959a4c2d076530b704dbe7c32648fa69de21fde01b935081c63ccc","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T05:04:08.413615Z","signature_b64":"kdaDCZmq7yQB32GFe46tgGDbDYfOrAt2j4x4tH3RyCykZatjpuAmWkahd4n4TtTJEIE0Tgzmj+0VDYxvmeqcCA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"e0a1c43295959a4c2d076530b704dbe7c32648fa69de21fde01b935081c63ccc","last_reissued_at":"2026-07-05T05:04:08.413187Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T05:04:08.413187Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2003.10509","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-07-05T05:04:08Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ibkABmjB49wjs7mbIms2Fn9iP60PI1icyQYwrch5MqZZK9Itauowzp3allvuEqxW+iULv80u4sp9AaZ4fzNyDA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-08T23:25:50.490549Z"},"content_sha256":"5a539efa0ec45d34303a5f8ac77c4eac0d126f1ba97a9b8627de7fe09e7ad254","schema_version":"1.0","event_id":"sha256:5a539efa0ec45d34303a5f8ac77c4eac0d126f1ba97a9b8627de7fe09e7ad254"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2020:4CQ4IMUVSWNEYLIHMUYLOBG347","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Defect dynamics in growing bacterial colonies","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cond-mat.soft","q-bio.PE"],"primary_cat":"physics.bio-ph","authors_text":"Duco van Holthe tot Echten, Gerhard Nordemann, Martijn Wehrens, Rachel Los, Sander J. Tans, Timon Idema","submitted_at":"2020-03-23T19:38:14Z","abstract_excerpt":"Colonies of rod-shaped bacteria constitute a system of colloidal active matter with nematic properties. As a single initial bacterium multiplies through repeated divisions, the resulting colony quickly loses long-range orientational order, but retains locally ordered domains. At the boundaries of these domains, topological defects emerge, which move around randomly as the colony grows. In both experiments and simulations, we find that these defects are created at a rate that corresponds to the exponential growth of the colony, resulting in a stable defect density. Both this defect density and "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2003.10509","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2003.10509/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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":"2026-07-05T05:04:08Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"7gLCYalM7abolscjo3jvRag91MA6E2284HTF0Z7VThmaL/IOZOec7fPQ6fbz3wxqn9pbLrcwN7hU4tqfak3XBQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-08T23:25:50.491100Z"},"content_sha256":"c27bc102b89bfd697c43f8ef8b545f80bbdfa909088637b7e91d921ba06678ef","schema_version":"1.0","event_id":"sha256:c27bc102b89bfd697c43f8ef8b545f80bbdfa909088637b7e91d921ba06678ef"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/4CQ4IMUVSWNEYLIHMUYLOBG347/bundle.json","state_url":"https://pith.science/pith/4CQ4IMUVSWNEYLIHMUYLOBG347/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/4CQ4IMUVSWNEYLIHMUYLOBG347/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":"2026-08-08T23:25:50Z","links":{"resolver":"https://pith.science/pith/4CQ4IMUVSWNEYLIHMUYLOBG347","bundle":"https://pith.science/pith/4CQ4IMUVSWNEYLIHMUYLOBG347/bundle.json","state":"https://pith.science/pith/4CQ4IMUVSWNEYLIHMUYLOBG347/state.json","well_known_bundle":"https://pith.science/.well-known/pith/4CQ4IMUVSWNEYLIHMUYLOBG347/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2020:4CQ4IMUVSWNEYLIHMUYLOBG347","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":"5a3cd68996f378cfea88861e01c781d190c0bfe35d88181b5cbd1f6ae318dc8a","cross_cats_sorted":["cond-mat.soft","q-bio.PE"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.bio-ph","submitted_at":"2020-03-23T19:38:14Z","title_canon_sha256":"e648f4ee10355ca64df6ea198fd8882b55276e1a81f60abbe15d8d8c46a3bfc3"},"schema_version":"1.0","source":{"id":"2003.10509","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2003.10509","created_at":"2026-07-05T05:04:08Z"},{"alias_kind":"arxiv_version","alias_value":"2003.10509v2","created_at":"2026-07-05T05:04:08Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2003.10509","created_at":"2026-07-05T05:04:08Z"},{"alias_kind":"pith_short_12","alias_value":"4CQ4IMUVSWNE","created_at":"2026-07-05T05:04:08Z"},{"alias_kind":"pith_short_16","alias_value":"4CQ4IMUVSWNEYLIH","created_at":"2026-07-05T05:04:08Z"},{"alias_kind":"pith_short_8","alias_value":"4CQ4IMUV","created_at":"2026-07-05T05:04:08Z"}],"graph_snapshots":[{"event_id":"sha256:c27bc102b89bfd697c43f8ef8b545f80bbdfa909088637b7e91d921ba06678ef","target":"graph","created_at":"2026-07-05T05:04:08Z","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"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2003.10509/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Colonies of rod-shaped bacteria constitute a system of colloidal active matter with nematic properties. As a single initial bacterium multiplies through repeated divisions, the resulting colony quickly loses long-range orientational order, but retains locally ordered domains. At the boundaries of these domains, topological defects emerge, which move around randomly as the colony grows. In both experiments and simulations, we find that these defects are created at a rate that corresponds to the exponential growth of the colony, resulting in a stable defect density. Both this defect density and ","authors_text":"Duco van Holthe tot Echten, Gerhard Nordemann, Martijn Wehrens, Rachel Los, Sander J. Tans, Timon Idema","cross_cats":["cond-mat.soft","q-bio.PE"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.bio-ph","submitted_at":"2020-03-23T19:38:14Z","title":"Defect dynamics in growing bacterial colonies"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2003.10509","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":"sha256:5a539efa0ec45d34303a5f8ac77c4eac0d126f1ba97a9b8627de7fe09e7ad254","target":"record","created_at":"2026-07-05T05:04:08Z","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":"5a3cd68996f378cfea88861e01c781d190c0bfe35d88181b5cbd1f6ae318dc8a","cross_cats_sorted":["cond-mat.soft","q-bio.PE"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.bio-ph","submitted_at":"2020-03-23T19:38:14Z","title_canon_sha256":"e648f4ee10355ca64df6ea198fd8882b55276e1a81f60abbe15d8d8c46a3bfc3"},"schema_version":"1.0","source":{"id":"2003.10509","kind":"arxiv","version":2}},"canonical_sha256":"e0a1c43295959a4c2d076530b704dbe7c32648fa69de21fde01b935081c63ccc","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"e0a1c43295959a4c2d076530b704dbe7c32648fa69de21fde01b935081c63ccc","first_computed_at":"2026-07-05T05:04:08.413187Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T05:04:08.413187Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"kdaDCZmq7yQB32GFe46tgGDbDYfOrAt2j4x4tH3RyCykZatjpuAmWkahd4n4TtTJEIE0Tgzmj+0VDYxvmeqcCA==","signature_status":"signed_v1","signed_at":"2026-07-05T05:04:08.413615Z","signed_message":"canonical_sha256_bytes"},"source_id":"2003.10509","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:5a539efa0ec45d34303a5f8ac77c4eac0d126f1ba97a9b8627de7fe09e7ad254","sha256:c27bc102b89bfd697c43f8ef8b545f80bbdfa909088637b7e91d921ba06678ef"],"state_sha256":"f73340aa1ca83874a68e0cb5c8a34a8556f3fd31cf90cfb434e5b251c0602855"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"paz3MfDmRxZUj1LbNODMnqg8mO+J8mQORnRw5Fe+7HSYvDN0aXwDPhQSo/YqIfOh1JgKCmAQrLufhs2TH1loDw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-08T23:25:50.496411Z","bundle_sha256":"7cc87bb6b724a45918cc30cfc223514edc8ddca217a2cf9c27565c3579609d42"}}