{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2026:SIWNBHKK7RE52TJ7WXJQOIBVVR","short_pith_number":"pith:SIWNBHKK","schema_version":"1.0","canonical_sha256":"922cd09d4afc49dd4d3fb5d3072035ac4721e1a84b1fdb657a8d7a28eb0a6a81","source":{"kind":"arxiv","id":"2608.11042","version":1},"attestation_state":"computed","paper":{"title":"Entanglement depth and ancilla efficiency in quantum channel estimation","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"Javid Naikoo","submitted_at":"2026-08-11T15:15:40Z","abstract_excerpt":"We study the role of ancillary entanglement in quantum channel parameter estimation and investigate the minimal ancilla dimension required to achieve the maximum Fisher information. We introduce the $k$-ancilla Fisher information, which quantifies the optimal estimation precision achievable with input states of rank at most $k$, and derive a variational characterization in terms of a rank-constrained optimization problem. This formulation leads to a simple characterization of the minimum ancilla dimension $k^*$ required for optimal estimation, given by the minimum rank among the maximizers of "},"verification_status":{"content_addressed":true,"pith_receipt":true,"author_attested":false,"weak_author_claims":0,"strong_author_claims":0,"externally_anchored":false,"storage_verified":false,"citation_signatures":0,"replication_records":0,"graph_snapshot":true,"references_resolved":false,"formal_links_present":false},"canonical_record":{"source":{"id":"2608.11042","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"quant-ph","submitted_at":"2026-08-11T15:15:40Z","cross_cats_sorted":[],"title_canon_sha256":"f28e69c171308f1bcd5fc9dee2cc601424215b11d06272fb58555f9d3d33fe6e","abstract_canon_sha256":"18215e3c75f285f2081c8e2ff829e64d704c5982d20ad7ad088596107088205b"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-08-12T01:24:29.093310Z","signature_b64":"A1PsuaJquUAdXhrxkJ4yBG5ccoGqmK8x+3PTKN2LxKtGr57yYLWD8TwXjHSTMheEul/LOWLOuj7szyWMWdO9Aw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"922cd09d4afc49dd4d3fb5d3072035ac4721e1a84b1fdb657a8d7a28eb0a6a81","last_reissued_at":"2026-08-12T01:24:29.091207Z","signature_status":"signed_v1","first_computed_at":"2026-08-12T01:24:29.091207Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Entanglement depth and ancilla efficiency in quantum channel estimation","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"Javid Naikoo","submitted_at":"2026-08-11T15:15:40Z","abstract_excerpt":"We study the role of ancillary entanglement in quantum channel parameter estimation and investigate the minimal ancilla dimension required to achieve the maximum Fisher information. We introduce the $k$-ancilla Fisher information, which quantifies the optimal estimation precision achievable with input states of rank at most $k$, and derive a variational characterization in terms of a rank-constrained optimization problem. This formulation leads to a simple characterization of the minimum ancilla dimension $k^*$ required for optimal estimation, given by the minimum rank among the maximizers of "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2608.11042","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2608.11042/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"},"aliases":[{"alias_kind":"arxiv","alias_value":"2608.11042","created_at":"2026-08-12T01:24:29.095191+00:00"},{"alias_kind":"arxiv_version","alias_value":"2608.11042v1","created_at":"2026-08-12T01:24:29.095191+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2608.11042","created_at":"2026-08-12T01:24:29.095191+00:00"},{"alias_kind":"pith_short_12","alias_value":"SIWNBHKK7RE5","created_at":"2026-08-12T01:24:29.095191+00:00"},{"alias_kind":"pith_short_16","alias_value":"SIWNBHKK7RE52TJ7","created_at":"2026-08-12T01:24:29.095191+00:00"},{"alias_kind":"pith_short_8","alias_value":"SIWNBHKK","created_at":"2026-08-12T01:24:29.095191+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":0,"internal_anchor_count":0,"sample":[]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/SIWNBHKK7RE52TJ7WXJQOIBVVR","json":"https://pith.science/pith/SIWNBHKK7RE52TJ7WXJQOIBVVR.json","graph_json":"https://pith.science/api/pith-number/SIWNBHKK7RE52TJ7WXJQOIBVVR/graph.json","events_json":"https://pith.science/api/pith-number/SIWNBHKK7RE52TJ7WXJQOIBVVR/events.json","paper":"https://pith.science/paper/SIWNBHKK"},"agent_actions":{"view_html":"https://pith.science/pith/SIWNBHKK7RE52TJ7WXJQOIBVVR","download_json":"https://pith.science/pith/SIWNBHKK7RE52TJ7WXJQOIBVVR.json","view_paper":"https://pith.science/paper/SIWNBHKK","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=2608.11042&json=true","fetch_graph":"https://pith.science/api/pith-number/SIWNBHKK7RE52TJ7WXJQOIBVVR/graph.json","fetch_events":"https://pith.science/api/pith-number/SIWNBHKK7RE52TJ7WXJQOIBVVR/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/SIWNBHKK7RE52TJ7WXJQOIBVVR/action/timestamp_anchor","attest_storage":"https://pith.science/pith/SIWNBHKK7RE52TJ7WXJQOIBVVR/action/storage_attestation","attest_author":"https://pith.science/pith/SIWNBHKK7RE52TJ7WXJQOIBVVR/action/author_attestation","sign_citation":"https://pith.science/pith/SIWNBHKK7RE52TJ7WXJQOIBVVR/action/citation_signature","submit_replication":"https://pith.science/pith/SIWNBHKK7RE52TJ7WXJQOIBVVR/action/replication_record"}},"created_at":"2026-08-12T01:24:29.095191+00:00","updated_at":"2026-08-12T01:24:29.095191+00:00"}