{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2009:4YAGQHD45TIIKZFJPUNL3P3QHS","short_pith_number":"pith:4YAGQHD4","canonical_record":{"source":{"id":"0909.2477","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2009-09-14T06:39:41Z","cross_cats_sorted":[],"title_canon_sha256":"da12d72746b8d4286b356ed30b20ff5c79fb1a9bad880398c387689b69e7bc03","abstract_canon_sha256":"4f322d73d641b4a34ccfbf245e2682cbc542a259a2a32dc4713717117bc36a75"},"schema_version":"1.0"},"canonical_sha256":"e600681c7cecd08564a97d1abdbf703c96083c00c23ff8e1b7ce35cbcd5919eb","source":{"kind":"arxiv","id":"0909.2477","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"0909.2477","created_at":"2026-05-18T04:39:16Z"},{"alias_kind":"arxiv_version","alias_value":"0909.2477v2","created_at":"2026-05-18T04:39:16Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.0909.2477","created_at":"2026-05-18T04:39:16Z"},{"alias_kind":"pith_short_12","alias_value":"4YAGQHD45TII","created_at":"2026-05-18T12:25:58Z"},{"alias_kind":"pith_short_16","alias_value":"4YAGQHD45TIIKZFJ","created_at":"2026-05-18T12:25:58Z"},{"alias_kind":"pith_short_8","alias_value":"4YAGQHD4","created_at":"2026-05-18T12:25:58Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2009:4YAGQHD45TIIKZFJPUNL3P3QHS","target":"record","payload":{"canonical_record":{"source":{"id":"0909.2477","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2009-09-14T06:39:41Z","cross_cats_sorted":[],"title_canon_sha256":"da12d72746b8d4286b356ed30b20ff5c79fb1a9bad880398c387689b69e7bc03","abstract_canon_sha256":"4f322d73d641b4a34ccfbf245e2682cbc542a259a2a32dc4713717117bc36a75"},"schema_version":"1.0"},"canonical_sha256":"e600681c7cecd08564a97d1abdbf703c96083c00c23ff8e1b7ce35cbcd5919eb","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T04:39:16.845279Z","signature_b64":"QNJAGglJRTmtpwWjRKQCrW0vmf+WyW3r8k71/xXrQn11h22Iqx5ptxcbKzGGkoU4ErUai7MO50xuli1CMsmnDQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"e600681c7cecd08564a97d1abdbf703c96083c00c23ff8e1b7ce35cbcd5919eb","last_reissued_at":"2026-05-18T04:39:16.844470Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T04:39:16.844470Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"0909.2477","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":"2026-05-18T04:39:16Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"kXmzlQyEsNHnBMYS2ZASL6noDmTjdPyPRXMEA872+Ftj0pIzn8yrE7YNwlEtfwJk1rlb9aj/8my1IeYwImU4Aw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-30T08:55:53.303044Z"},"content_sha256":"18937fa5d114355f82046733c5ba4be69a84bc408de7b27ef25a4c3f8b212a8d","schema_version":"1.0","event_id":"sha256:18937fa5d114355f82046733c5ba4be69a84bc408de7b27ef25a4c3f8b212a8d"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2009:4YAGQHD45TIIKZFJPUNL3P3QHS","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Collective modes of a helical liquid","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cond-mat.mes-hall","authors_text":"Shou-Cheng Zhang, S. Raghu, Suk Bum Chung, Xiao-Liang Qi","submitted_at":"2009-09-14T06:39:41Z","abstract_excerpt":"We study low energy collective modes and transport properties of the \"helical metal\" on the surface of a topological insulator. At low energies, electrical transport and spin dynamics at the surface are exactly related by an operator identity equating the electric current to the in-plane components of the spin degrees of freedom. From this relation it follows that an undamped spin wave always accompanies the sound mode in the helical metal -- thus it is possible to `hear' the sound of spins. In the presence of long range Coulomb interactions, the surface plasmon mode is also coupled to the spi"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0909.2477","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":""},"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":"2026-05-18T04:39:16Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"br4UfxPwTMFeEJ8jh9brqH97cYYe/ZnewV6JP42f5SOo2+MUjO2NyPwJsHYleFHlO+dP+2jiNc9EUsdc/bVECA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-30T08:55:53.303691Z"},"content_sha256":"d63989130265e4bc520675c3b283a068a25d3e2ef2eb356b93b2ae549b059fe6","schema_version":"1.0","event_id":"sha256:d63989130265e4bc520675c3b283a068a25d3e2ef2eb356b93b2ae549b059fe6"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/4YAGQHD45TIIKZFJPUNL3P3QHS/bundle.json","state_url":"https://pith.science/pith/4YAGQHD45TIIKZFJPUNL3P3QHS/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/4YAGQHD45TIIKZFJPUNL3P3QHS/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":"2026-05-30T08:55:53Z","links":{"resolver":"https://pith.science/pith/4YAGQHD45TIIKZFJPUNL3P3QHS","bundle":"https://pith.science/pith/4YAGQHD45TIIKZFJPUNL3P3QHS/bundle.json","state":"https://pith.science/pith/4YAGQHD45TIIKZFJPUNL3P3QHS/state.json","well_known_bundle":"https://pith.science/.well-known/pith/4YAGQHD45TIIKZFJPUNL3P3QHS/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2009:4YAGQHD45TIIKZFJPUNL3P3QHS","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":"4f322d73d641b4a34ccfbf245e2682cbc542a259a2a32dc4713717117bc36a75","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2009-09-14T06:39:41Z","title_canon_sha256":"da12d72746b8d4286b356ed30b20ff5c79fb1a9bad880398c387689b69e7bc03"},"schema_version":"1.0","source":{"id":"0909.2477","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"0909.2477","created_at":"2026-05-18T04:39:16Z"},{"alias_kind":"arxiv_version","alias_value":"0909.2477v2","created_at":"2026-05-18T04:39:16Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.0909.2477","created_at":"2026-05-18T04:39:16Z"},{"alias_kind":"pith_short_12","alias_value":"4YAGQHD45TII","created_at":"2026-05-18T12:25:58Z"},{"alias_kind":"pith_short_16","alias_value":"4YAGQHD45TIIKZFJ","created_at":"2026-05-18T12:25:58Z"},{"alias_kind":"pith_short_8","alias_value":"4YAGQHD4","created_at":"2026-05-18T12:25:58Z"}],"graph_snapshots":[{"event_id":"sha256:d63989130265e4bc520675c3b283a068a25d3e2ef2eb356b93b2ae549b059fe6","target":"graph","created_at":"2026-05-18T04:39:16Z","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":"We study low energy collective modes and transport properties of the \"helical metal\" on the surface of a topological insulator. At low energies, electrical transport and spin dynamics at the surface are exactly related by an operator identity equating the electric current to the in-plane components of the spin degrees of freedom. From this relation it follows that an undamped spin wave always accompanies the sound mode in the helical metal -- thus it is possible to `hear' the sound of spins. In the presence of long range Coulomb interactions, the surface plasmon mode is also coupled to the spi","authors_text":"Shou-Cheng Zhang, S. Raghu, Suk Bum Chung, Xiao-Liang Qi","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2009-09-14T06:39:41Z","title":"Collective modes of a helical liquid"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0909.2477","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":"sha256:18937fa5d114355f82046733c5ba4be69a84bc408de7b27ef25a4c3f8b212a8d","target":"record","created_at":"2026-05-18T04:39:16Z","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":"4f322d73d641b4a34ccfbf245e2682cbc542a259a2a32dc4713717117bc36a75","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2009-09-14T06:39:41Z","title_canon_sha256":"da12d72746b8d4286b356ed30b20ff5c79fb1a9bad880398c387689b69e7bc03"},"schema_version":"1.0","source":{"id":"0909.2477","kind":"arxiv","version":2}},"canonical_sha256":"e600681c7cecd08564a97d1abdbf703c96083c00c23ff8e1b7ce35cbcd5919eb","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"e600681c7cecd08564a97d1abdbf703c96083c00c23ff8e1b7ce35cbcd5919eb","first_computed_at":"2026-05-18T04:39:16.844470Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T04:39:16.844470Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"QNJAGglJRTmtpwWjRKQCrW0vmf+WyW3r8k71/xXrQn11h22Iqx5ptxcbKzGGkoU4ErUai7MO50xuli1CMsmnDQ==","signature_status":"signed_v1","signed_at":"2026-05-18T04:39:16.845279Z","signed_message":"canonical_sha256_bytes"},"source_id":"0909.2477","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:18937fa5d114355f82046733c5ba4be69a84bc408de7b27ef25a4c3f8b212a8d","sha256:d63989130265e4bc520675c3b283a068a25d3e2ef2eb356b93b2ae549b059fe6"],"state_sha256":"644bbf974b4daa8c6eb13c23e6e33b4510ded27beea104192b3e73bc515a2877"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"zylcv5HlKSaMBtQcP/RsOD1sOJsuinLSLZ4PSIZyRMbvXwAyYlarCUcsRBXQpLrFa7XbLfmwxrkXorbEpnHkAw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-30T08:55:53.306898Z","bundle_sha256":"1f038daa3993cf908262d07afc89c9f1ea4e95bf5d85c5e76963e65062256cb4"}}