{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2025:P2JIFRQ7SZOGPAYNJ2W2275TYY","short_pith_number":"pith:P2JIFRQ7","canonical_record":{"source":{"id":"2505.20137","kind":"arxiv","version":5},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2025-05-26T15:39:16Z","cross_cats_sorted":["cs.AI"],"title_canon_sha256":"7f3d1012eeae4f11fc9a7b23f258c09ed83f31695559acc095be1da0dddccd44","abstract_canon_sha256":"55140c1579f1d140ac4c3801eecf50f29f12da82c7073ca4a30fad4f0f77b6b3"},"schema_version":"1.0"},"canonical_sha256":"7e9282c61f965c67830d4eadad7fb3c6202df84fe2ea45e82e4972c4791fa07b","source":{"kind":"arxiv","id":"2505.20137","version":5},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2505.20137","created_at":"2026-06-09T02:07:04Z"},{"alias_kind":"arxiv_version","alias_value":"2505.20137v5","created_at":"2026-06-09T02:07:04Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2505.20137","created_at":"2026-06-09T02:07:04Z"},{"alias_kind":"pith_short_12","alias_value":"P2JIFRQ7SZOG","created_at":"2026-06-09T02:07:04Z"},{"alias_kind":"pith_short_16","alias_value":"P2JIFRQ7SZOGPAYN","created_at":"2026-06-09T02:07:04Z"},{"alias_kind":"pith_short_8","alias_value":"P2JIFRQ7","created_at":"2026-06-09T02:07:04Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2025:P2JIFRQ7SZOGPAYNJ2W2275TYY","target":"record","payload":{"canonical_record":{"source":{"id":"2505.20137","kind":"arxiv","version":5},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2025-05-26T15:39:16Z","cross_cats_sorted":["cs.AI"],"title_canon_sha256":"7f3d1012eeae4f11fc9a7b23f258c09ed83f31695559acc095be1da0dddccd44","abstract_canon_sha256":"55140c1579f1d140ac4c3801eecf50f29f12da82c7073ca4a30fad4f0f77b6b3"},"schema_version":"1.0"},"canonical_sha256":"7e9282c61f965c67830d4eadad7fb3c6202df84fe2ea45e82e4972c4791fa07b","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-06-09T02:07:04.131425Z","signature_b64":"knoPYB755OPnLtgbySRy0jHqgCIDN82dGXnyoORIMdtHZNaLsuPZLaC1Yr30WrSUvy9dyE/fcT2FcjP3U1KrAQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"7e9282c61f965c67830d4eadad7fb3c6202df84fe2ea45e82e4972c4791fa07b","last_reissued_at":"2026-06-09T02:07:04.130400Z","signature_status":"signed_v1","first_computed_at":"2026-06-09T02:07:04.130400Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2505.20137","source_version":5,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-06-09T02:07:04Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"QK4L4ag/ZBvdeU9lhkc31yANrZkNIl87Wz+CQGH0qBcVUmDHjAG6rvdzh5UqSbNjce8PPYNHjcxlf8hGZIOECw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-09T17:51:51.408577Z"},"content_sha256":"72dd8858e3bd20a3462bfa9fc6b57e474ba1e246802c0c2ac5e05c3ed1ec3139","schema_version":"1.0","event_id":"sha256:72dd8858e3bd20a3462bfa9fc6b57e474ba1e246802c0c2ac5e05c3ed1ec3139"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2025:P2JIFRQ7SZOGPAYNJ2W2275TYY","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"ePC: Fast and Deep Predictive Coding in Digital Simulation","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cs.AI"],"primary_cat":"cs.LG","authors_text":"C\\'edric Goemaere, Gaspard Oliviers, Rafal Bogacz, Thomas Demeester","submitted_at":"2025-05-26T15:39:16Z","abstract_excerpt":"Predictive Coding (PC) offers a brain-inspired alternative to backpropagation for neural network training, described as a physical system minimizing its internal energy. However, in practice, PC is predominantly digitally simulated, requiring excessive amounts of compute while struggling to scale to deeper architectures. This paper reformulates PC to overcome this hardware-algorithm mismatch. First, we uncover how the canonical state-based formulation of PC (sPC) is, by design, deeply inefficient in digital simulation, inevitably resulting in exponential signal decay that stalls the entire min"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2505.20137","kind":"arxiv","version":5},"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/2505.20137/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":"2026-06-09T02:07:04Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"7Od8Z4Xn4+yjUd54xkCh9KzOEijpzOBFX71gZyBD8Fpu+2PxbhW+S8zIPRJeAcz9xckUIXu0vcBK4C5xXFweCQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-09T17:51:51.408951Z"},"content_sha256":"92e8c3c2a1a52b4a7078b72893ad011485d1a13817d49066e3ab9f72bd569667","schema_version":"1.0","event_id":"sha256:92e8c3c2a1a52b4a7078b72893ad011485d1a13817d49066e3ab9f72bd569667"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/P2JIFRQ7SZOGPAYNJ2W2275TYY/bundle.json","state_url":"https://pith.science/pith/P2JIFRQ7SZOGPAYNJ2W2275TYY/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/P2JIFRQ7SZOGPAYNJ2W2275TYY/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":"2026-06-09T17:51:51Z","links":{"resolver":"https://pith.science/pith/P2JIFRQ7SZOGPAYNJ2W2275TYY","bundle":"https://pith.science/pith/P2JIFRQ7SZOGPAYNJ2W2275TYY/bundle.json","state":"https://pith.science/pith/P2JIFRQ7SZOGPAYNJ2W2275TYY/state.json","well_known_bundle":"https://pith.science/.well-known/pith/P2JIFRQ7SZOGPAYNJ2W2275TYY/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2025:P2JIFRQ7SZOGPAYNJ2W2275TYY","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":"55140c1579f1d140ac4c3801eecf50f29f12da82c7073ca4a30fad4f0f77b6b3","cross_cats_sorted":["cs.AI"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2025-05-26T15:39:16Z","title_canon_sha256":"7f3d1012eeae4f11fc9a7b23f258c09ed83f31695559acc095be1da0dddccd44"},"schema_version":"1.0","source":{"id":"2505.20137","kind":"arxiv","version":5}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2505.20137","created_at":"2026-06-09T02:07:04Z"},{"alias_kind":"arxiv_version","alias_value":"2505.20137v5","created_at":"2026-06-09T02:07:04Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2505.20137","created_at":"2026-06-09T02:07:04Z"},{"alias_kind":"pith_short_12","alias_value":"P2JIFRQ7SZOG","created_at":"2026-06-09T02:07:04Z"},{"alias_kind":"pith_short_16","alias_value":"P2JIFRQ7SZOGPAYN","created_at":"2026-06-09T02:07:04Z"},{"alias_kind":"pith_short_8","alias_value":"P2JIFRQ7","created_at":"2026-06-09T02:07:04Z"}],"graph_snapshots":[{"event_id":"sha256:92e8c3c2a1a52b4a7078b72893ad011485d1a13817d49066e3ab9f72bd569667","target":"graph","created_at":"2026-06-09T02:07:04Z","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/2505.20137/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Predictive Coding (PC) offers a brain-inspired alternative to backpropagation for neural network training, described as a physical system minimizing its internal energy. However, in practice, PC is predominantly digitally simulated, requiring excessive amounts of compute while struggling to scale to deeper architectures. This paper reformulates PC to overcome this hardware-algorithm mismatch. First, we uncover how the canonical state-based formulation of PC (sPC) is, by design, deeply inefficient in digital simulation, inevitably resulting in exponential signal decay that stalls the entire min","authors_text":"C\\'edric Goemaere, Gaspard Oliviers, Rafal Bogacz, Thomas Demeester","cross_cats":["cs.AI"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2025-05-26T15:39:16Z","title":"ePC: Fast and Deep Predictive Coding in Digital Simulation"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2505.20137","kind":"arxiv","version":5},"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":"sha256:72dd8858e3bd20a3462bfa9fc6b57e474ba1e246802c0c2ac5e05c3ed1ec3139","target":"record","created_at":"2026-06-09T02:07:04Z","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":"55140c1579f1d140ac4c3801eecf50f29f12da82c7073ca4a30fad4f0f77b6b3","cross_cats_sorted":["cs.AI"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2025-05-26T15:39:16Z","title_canon_sha256":"7f3d1012eeae4f11fc9a7b23f258c09ed83f31695559acc095be1da0dddccd44"},"schema_version":"1.0","source":{"id":"2505.20137","kind":"arxiv","version":5}},"canonical_sha256":"7e9282c61f965c67830d4eadad7fb3c6202df84fe2ea45e82e4972c4791fa07b","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"7e9282c61f965c67830d4eadad7fb3c6202df84fe2ea45e82e4972c4791fa07b","first_computed_at":"2026-06-09T02:07:04.130400Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-06-09T02:07:04.130400Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"knoPYB755OPnLtgbySRy0jHqgCIDN82dGXnyoORIMdtHZNaLsuPZLaC1Yr30WrSUvy9dyE/fcT2FcjP3U1KrAQ==","signature_status":"signed_v1","signed_at":"2026-06-09T02:07:04.131425Z","signed_message":"canonical_sha256_bytes"},"source_id":"2505.20137","source_kind":"arxiv","source_version":5}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:72dd8858e3bd20a3462bfa9fc6b57e474ba1e246802c0c2ac5e05c3ed1ec3139","sha256:92e8c3c2a1a52b4a7078b72893ad011485d1a13817d49066e3ab9f72bd569667"],"state_sha256":"5aac693230dbe7556d01e2bb1b99bc7a3e55e1edd612469f106cb7dc21a7d8e8"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"XLoAVQQqwZgbfymbKR2no5WzNtaajhVgwvx+YRrwSv0LydDiUumpqwtXo675ATr3vJdEv22tVT115CyTztnBDg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-09T17:51:51.411073Z","bundle_sha256":"f80d73b5d97cc6b663d9c8a196e6f4c95d8edcf388ad1a8fbedc01f98d484553"}}