{"paper":{"title":"Light Propagation Prescriptions for Black Hole Movies","license":"http://creativecommons.org/licenses/by/4.0/","headline":"Fast and slow light prescriptions for black hole movies differ by tens of percent when variability is rapid.","cross_cats":["gr-qc"],"primary_cat":"astro-ph.HE","authors_text":"Alejandro C\\'ardenas-Avenda\\~no, Daniel Rojas-Paternina","submitted_at":"2026-05-12T19:06:19Z","abstract_excerpt":"The spatiotemporal content of a black-hole movie is set jointly by source variability and by the distribution of light-travel times across the image. In the slow-light prescription, an image evaluated at fixed observer time contains photons emitted at different source times, whereas in fast light all rays sample a single source emission time. In this work we compare these light-propagation prescriptions through the lensing-band structure of Kerr geodesic delays in a controlled semi-analytic setting. For a given emitting geometry, black-hole spin, and observer inclination, we show how the coord"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"when the intrinsic variability timescale is comparable to, or shorter than, the relevant delay spread, the high-inclination mismatch between fast- and slow-light curves can reach several tens of percent.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The comparison holds in a controlled semi-analytic setting for a given emitting geometry, black-hole spin, and observer inclination, with delay distributions directly comparable to source correlation time.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Brisk light bridges fast and slow prescriptions by using dominant temporal intervals per lensing band, with mismatches reaching tens of percent when source variability is shorter than delay spreads.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Fast and slow light prescriptions for black hole movies differ by tens of percent when variability is rapid.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"72f3120c7d591ceb5b19d0150113c95713055b966c6813a530dc9dfc321abf98"},"source":{"id":"2605.12659","kind":"arxiv","version":1},"verdict":{"id":"c363718f-cf9c-4b96-ba4e-39f6d667da51","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-14T20:11:47.693807Z","strongest_claim":"when the intrinsic variability timescale is comparable to, or shorter than, the relevant delay spread, the high-inclination mismatch between fast- and slow-light curves can reach several tens of percent.","one_line_summary":"Brisk light bridges fast and slow prescriptions by using dominant temporal intervals per lensing band, with mismatches reaching tens of percent when source variability is shorter than delay spreads.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The comparison holds in a controlled semi-analytic setting for a given emitting geometry, black-hole spin, and observer inclination, with delay distributions directly comparable to source correlation time.","pith_extraction_headline":"Fast and slow light prescriptions for black hole movies differ by tens of percent when variability is rapid."},"references":{"count":22,"sample":[{"doi":"","year":2020,"title":"Lensing by Kerr Black Holes","work_id":"1a930d13-054f-45e0-a91e-abb42985bbf8","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2022,"title":"PATOKA: Simulating Electromagnetic Observables of Black Hole Accretion,","work_id":"5e36822e-a51d-43ca-92bd-a30d99c4e264","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2019,"title":"Akiyamaet al.(Event Horizon Telescope), First M87 event horizon telescope results","work_id":"59a7a553-4c6f-48fe-a7ba-2caf87d0e7f6","ref_index":3,"cited_arxiv_id":"1906.11242","is_internal_anchor":true},{"doi":"","year":2022,"title":"First Sagittarius A* Event Horizon Telescope Results. V. Testing Astrophysical Models of the Galactic Center Black Hole","work_id":"4a6964be-49a5-4708-96b9-2af27785cc09","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2018,"title":"RAPTOR I: Time-dependent radiative transfer in arbitrary spacetimes","work_id":"3d839ae5-c127-40c2-9113-db1dfd2942c5","ref_index":5,"cited_arxiv_id":"1801.10452","is_internal_anchor":true}],"resolved_work":22,"snapshot_sha256":"5da153417e8f6a49ec4e16ad23377f7794fff2904759337f18f81143ef2d0d97","internal_anchors":3},"formal_canon":{"evidence_count":2,"snapshot_sha256":"3b7b345b0aa33d3e9d2a6eccc65252f3177a5cde549c288beab564d4fac17f61"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}