{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:BLNFFCNPCHLJYCT7ISZPVPKVH2","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":"68a9fb8d53db3c9f500dcc05ffc2397300696227bb30394df51eaacf13448ad8","cross_cats_sorted":["cs.DM","math.CO"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.DS","submitted_at":"2019-02-05T09:39:55Z","title_canon_sha256":"91d5c774bd133c5b393a9227f5225d258c34c8bcfd2306d1c9b355fec0db7247"},"schema_version":"1.0","source":{"id":"1902.01609","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1902.01609","created_at":"2026-05-17T23:54:47Z"},{"alias_kind":"arxiv_version","alias_value":"1902.01609v1","created_at":"2026-05-17T23:54:47Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1902.01609","created_at":"2026-05-17T23:54:47Z"},{"alias_kind":"pith_short_12","alias_value":"BLNFFCNPCHLJ","created_at":"2026-05-18T12:33:12Z"},{"alias_kind":"pith_short_16","alias_value":"BLNFFCNPCHLJYCT7","created_at":"2026-05-18T12:33:12Z"},{"alias_kind":"pith_short_8","alias_value":"BLNFFCNP","created_at":"2026-05-18T12:33:12Z"}],"graph_snapshots":[{"event_id":"sha256:265d099866de6652b83f46cb3954392379657edfdfc570c27d3dbba403f2a064","target":"graph","created_at":"2026-05-17T23:54:47Z","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":"In the freeze-tag problem, one active robot must wake up many frozen robots. The robots are considered as points in a metric space, where active robots move at a constant rate and activate other robots by visiting them. In the (time-dependent) online variant of the problem, frozen robots are not revealed until a specified time. Hammar, Nilsson, and Persson have shown that no online algorithm can achieve a competitive ratio better than $7/3$ for online freeze-tag, and asked whether there is any $O(1)$-competitive algorithm. In this paper, we provide a $(1+\\sqrt{2})$-competitive algorithm for on","authors_text":"Josh Brunner, Julian Wellman","cross_cats":["cs.DM","math.CO"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.DS","submitted_at":"2019-02-05T09:39:55Z","title":"An Optimal Algorithm for Online Freeze-tag"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1902.01609","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":"sha256:256c4c8f100592dd69b5eb67c2f4209d759764305e9f731d5dc9e2db25532c0e","target":"record","created_at":"2026-05-17T23:54:47Z","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":"68a9fb8d53db3c9f500dcc05ffc2397300696227bb30394df51eaacf13448ad8","cross_cats_sorted":["cs.DM","math.CO"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.DS","submitted_at":"2019-02-05T09:39:55Z","title_canon_sha256":"91d5c774bd133c5b393a9227f5225d258c34c8bcfd2306d1c9b355fec0db7247"},"schema_version":"1.0","source":{"id":"1902.01609","kind":"arxiv","version":1}},"canonical_sha256":"0ada5289af11d69c0a7f44b2fabd553e9115635abefac942735fc12037e02d36","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"0ada5289af11d69c0a7f44b2fabd553e9115635abefac942735fc12037e02d36","first_computed_at":"2026-05-17T23:54:47.156722Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:54:47.156722Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"4ayEHrgaD0c1uRwWSQhya8XG58DHeX6w5jQv4nDhlW/rUki/ul+oIfLEgZziBQzlJsMFAqwgvxh7prqZEjBgBQ==","signature_status":"signed_v1","signed_at":"2026-05-17T23:54:47.157888Z","signed_message":"canonical_sha256_bytes"},"source_id":"1902.01609","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:256c4c8f100592dd69b5eb67c2f4209d759764305e9f731d5dc9e2db25532c0e","sha256:265d099866de6652b83f46cb3954392379657edfdfc570c27d3dbba403f2a064"],"state_sha256":"6fcb6631f4d635600e06fa69e72353bde832c0459ee0d70dfb5b172aa96cd19a"}