{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2026:BIOXLUMEWQYJU6FCASDFBNDHEP","short_pith_number":"pith:BIOXLUME","canonical_record":{"source":{"id":"2608.09625","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"quant-ph","submitted_at":"2026-08-10T14:05:36Z","cross_cats_sorted":["math-ph","math.MP"],"title_canon_sha256":"a997221f4af83be72d80b0d16be9241e5a9e79eb1e8c21087f5b1595ae11c8d2","abstract_canon_sha256":"6472304473a860015a3b3889cb6f4c0910237f38b27bad957cdea2ca2f6d94ef"},"schema_version":"1.0"},"canonical_sha256":"0a1d75d184b4309a78a2048650b46723c46278199fe0549622ff321f556844e4","source":{"kind":"arxiv","id":"2608.09625","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2608.09625","created_at":"2026-08-11T02:24:38Z"},{"alias_kind":"arxiv_version","alias_value":"2608.09625v1","created_at":"2026-08-11T02:24:38Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2608.09625","created_at":"2026-08-11T02:24:38Z"},{"alias_kind":"pith_short_12","alias_value":"BIOXLUMEWQYJ","created_at":"2026-08-11T02:24:38Z"},{"alias_kind":"pith_short_16","alias_value":"BIOXLUMEWQYJU6FC","created_at":"2026-08-11T02:24:38Z"},{"alias_kind":"pith_short_8","alias_value":"BIOXLUME","created_at":"2026-08-11T02:24:38Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2026:BIOXLUMEWQYJU6FCASDFBNDHEP","target":"record","payload":{"canonical_record":{"source":{"id":"2608.09625","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"quant-ph","submitted_at":"2026-08-10T14:05:36Z","cross_cats_sorted":["math-ph","math.MP"],"title_canon_sha256":"a997221f4af83be72d80b0d16be9241e5a9e79eb1e8c21087f5b1595ae11c8d2","abstract_canon_sha256":"6472304473a860015a3b3889cb6f4c0910237f38b27bad957cdea2ca2f6d94ef"},"schema_version":"1.0"},"canonical_sha256":"0a1d75d184b4309a78a2048650b46723c46278199fe0549622ff321f556844e4","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-08-11T02:24:38.731677Z","signature_b64":"li2e8EbOe55gKLTUuz/rB4UbudNP+Scn+r0LKOkCUgkrah2lYaRjqczV/sKy4+O8M8I+atMNEH7E411ka2e0BQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"0a1d75d184b4309a78a2048650b46723c46278199fe0549622ff321f556844e4","last_reissued_at":"2026-08-11T02:24:38.729868Z","signature_status":"signed_v1","first_computed_at":"2026-08-11T02:24:38.729868Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2608.09625","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":"2026-08-11T02:24:38Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"qII3SPaYLf5S9yntiXEE5yAK/LCmzkAeoWxNOROEL9erE5FNal4lR1mCclldCFsh5KUOUKQzff3t4Fju5o5eCA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-12T11:48:03.929535Z"},"content_sha256":"f27de7061778e4ac2affe6a5f098a2b2152b280e0d7102d836713cb37fb1febd","schema_version":"1.0","event_id":"sha256:f27de7061778e4ac2affe6a5f098a2b2152b280e0d7102d836713cb37fb1febd"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2026:BIOXLUMEWQYJU6FCASDFBNDHEP","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"A Design Space Study of Density Matrix Parameterizations for Diffusion-Based Quantum State Tomography","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["math-ph","math.MP"],"primary_cat":"quant-ph","authors_text":"Shuangju Chang","submitted_at":"2026-08-10T14:05:36Z","abstract_excerpt":"Diffusion-based quantum state tomography (QST) has shown promising results, but all existing methods implicitly adopt a single parameterization---typically Cholesky---without systematic evaluation. We present a design space study of density matrix parameterizations for diffusion QST, introducing a geometric framework based on the Jacobian Gram matrix $\\mathbf{J}^\\top\\mathbf{J}$ that quantifies two competing criteria: isometric conditioning and physical constraint satisfaction. Our calibration of seven parameterizations at 2- and 3-qubit scales reveals three key findings. First, isometry and co"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2608.09625","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/2608.09625/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":"2026-08-11T02:24:38Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"/nDFHH+U7f/rejsiNaz727DQg5XYevVKlPB3Z8xtrVEyWt61n6nV3vSGKiOIN0/71jOFLVu/XnrKDpYp6STCCQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-12T11:48:03.930416Z"},"content_sha256":"9584ae5f604219995199f78712b4215463bbf9d66b6767fac0f5e243e623bb90","schema_version":"1.0","event_id":"sha256:9584ae5f604219995199f78712b4215463bbf9d66b6767fac0f5e243e623bb90"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/BIOXLUMEWQYJU6FCASDFBNDHEP/bundle.json","state_url":"https://pith.science/pith/BIOXLUMEWQYJU6FCASDFBNDHEP/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/BIOXLUMEWQYJU6FCASDFBNDHEP/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":"2026-08-12T11:48:03Z","links":{"resolver":"https://pith.science/pith/BIOXLUMEWQYJU6FCASDFBNDHEP","bundle":"https://pith.science/pith/BIOXLUMEWQYJU6FCASDFBNDHEP/bundle.json","state":"https://pith.science/pith/BIOXLUMEWQYJU6FCASDFBNDHEP/state.json","well_known_bundle":"https://pith.science/.well-known/pith/BIOXLUMEWQYJU6FCASDFBNDHEP/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2026:BIOXLUMEWQYJU6FCASDFBNDHEP","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":"6472304473a860015a3b3889cb6f4c0910237f38b27bad957cdea2ca2f6d94ef","cross_cats_sorted":["math-ph","math.MP"],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"quant-ph","submitted_at":"2026-08-10T14:05:36Z","title_canon_sha256":"a997221f4af83be72d80b0d16be9241e5a9e79eb1e8c21087f5b1595ae11c8d2"},"schema_version":"1.0","source":{"id":"2608.09625","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2608.09625","created_at":"2026-08-11T02:24:38Z"},{"alias_kind":"arxiv_version","alias_value":"2608.09625v1","created_at":"2026-08-11T02:24:38Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2608.09625","created_at":"2026-08-11T02:24:38Z"},{"alias_kind":"pith_short_12","alias_value":"BIOXLUMEWQYJ","created_at":"2026-08-11T02:24:38Z"},{"alias_kind":"pith_short_16","alias_value":"BIOXLUMEWQYJU6FC","created_at":"2026-08-11T02:24:38Z"},{"alias_kind":"pith_short_8","alias_value":"BIOXLUME","created_at":"2026-08-11T02:24:38Z"}],"graph_snapshots":[{"event_id":"sha256:9584ae5f604219995199f78712b4215463bbf9d66b6767fac0f5e243e623bb90","target":"graph","created_at":"2026-08-11T02:24:38Z","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/2608.09625/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Diffusion-based quantum state tomography (QST) has shown promising results, but all existing methods implicitly adopt a single parameterization---typically Cholesky---without systematic evaluation. We present a design space study of density matrix parameterizations for diffusion QST, introducing a geometric framework based on the Jacobian Gram matrix $\\mathbf{J}^\\top\\mathbf{J}$ that quantifies two competing criteria: isometric conditioning and physical constraint satisfaction. Our calibration of seven parameterizations at 2- and 3-qubit scales reveals three key findings. First, isometry and co","authors_text":"Shuangju Chang","cross_cats":["math-ph","math.MP"],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"quant-ph","submitted_at":"2026-08-10T14:05:36Z","title":"A Design Space Study of Density Matrix Parameterizations for Diffusion-Based Quantum State Tomography"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2608.09625","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:f27de7061778e4ac2affe6a5f098a2b2152b280e0d7102d836713cb37fb1febd","target":"record","created_at":"2026-08-11T02:24:38Z","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":"6472304473a860015a3b3889cb6f4c0910237f38b27bad957cdea2ca2f6d94ef","cross_cats_sorted":["math-ph","math.MP"],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"quant-ph","submitted_at":"2026-08-10T14:05:36Z","title_canon_sha256":"a997221f4af83be72d80b0d16be9241e5a9e79eb1e8c21087f5b1595ae11c8d2"},"schema_version":"1.0","source":{"id":"2608.09625","kind":"arxiv","version":1}},"canonical_sha256":"0a1d75d184b4309a78a2048650b46723c46278199fe0549622ff321f556844e4","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"0a1d75d184b4309a78a2048650b46723c46278199fe0549622ff321f556844e4","first_computed_at":"2026-08-11T02:24:38.729868Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-08-11T02:24:38.729868Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"li2e8EbOe55gKLTUuz/rB4UbudNP+Scn+r0LKOkCUgkrah2lYaRjqczV/sKy4+O8M8I+atMNEH7E411ka2e0BQ==","signature_status":"signed_v1","signed_at":"2026-08-11T02:24:38.731677Z","signed_message":"canonical_sha256_bytes"},"source_id":"2608.09625","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:f27de7061778e4ac2affe6a5f098a2b2152b280e0d7102d836713cb37fb1febd","sha256:9584ae5f604219995199f78712b4215463bbf9d66b6767fac0f5e243e623bb90"],"state_sha256":"951d407873027d5e79e5b0a9ad301bf6966376673a2d5a63e4e60bcfc405a76c"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"bpIgP/BVkHLQy4j460Ty7d6i2LLZdoZHiChctp7QU5bTBYfsze+erGpswtzyu7c95KBk9r5DXej28hJmv0SKDA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-12T11:48:03.937687Z","bundle_sha256":"d04a31c9ffa60b95267f4fb4e97ce94c89c69350a614a016a297524680cd143a"}}