{"id":"W4405714396","doi":"10.1007/jhep07(2025)063","title":"Crossed products and quantum reference frames: on the observer-dependence of gravitational entropy","year":2025,"lang":"en","type":"preprint","venue":"Journal of High Energy Physics","topic":"Statistical Mechanics and Entropy","field":"Physics and Astronomy","cited_by":3,"is_retracted":false,"has_abstract":true,"ca_institutions":"Perimeter Institute","funders":"Ministry of Colleges and Universities; Institut Périmètre de physique théorique; Okinawa Institute of Science and Technology Graduate University; Government of Canada; John Templeton Foundation","keywords":"Reference frame; Observer (physics); Frame of reference; Entropy (arrow of time); Physics; Quantum; Gravitation; Theoretical physics; Statistical physics; Classical mechanics; Quantum mechanics; Computer science; Frame (networking)","routes":{"ca_aff":true,"ca_fund":true,"ca_venue":false,"about_ca":false,"invisible_to_affiliation_only":false},"retraction":null,"screen":null,"direct_labels":[],"prediction":{"model_version":"metacan-v3-hybrid-931329e0061c","candidate_categories":[],"consensus_categories":[],"category_scores_codex":[0.00346653,0.000572531,0.0004983518,0.001614896,0.001270871,0.002417031,0.001071899,0.001148102,0.004904326],"category_scores_gemma":[0.007711584,0.000334466,0.0007991327,0.0008996525,0.0059108,0.006444096,0.002790418,0.001688663,0.0003551753],"about_ca_system_candidate":false,"about_ca_system_consensus":false,"about_ca_system_score_codex":0.001220496,"about_ca_system_score_gemma":0.000521641,"about_ca_topic_candidate":false,"about_ca_topic_consensus":false,"about_ca_topic_score_codex":0.001317908,"about_ca_topic_score_gemma":0.0007749097,"domain_scores_codex":[0.9984328,0.000654578,0.00006756571,0.0002311639,0.0004115843,0.0002022936],"domain_scores_gemma":[0.9965005,0.001473097,0.0005532081,0.0007312643,0.0004362612,0.0003057747],"domain_codex":null,"domain_gemma":null,"domain_candidate":null,"domain_consensus":null,"study_design_codex":"theoretical_or_conceptual","study_design_gemma":"theoretical_or_conceptual","study_design_scores_codex":[0.000007151783,0.000003400995,0.00007319746,0.000006284759,0.000001589883,0.0000338385,0.0001122231,0.0009112183,0.0004104479,0.9976563,0.00009156841,0.0006925496],"study_design_scores_gemma":[0.000006712191,0.00003460722,0.0003200145,0.00001502952,0.00000497666,0.00007152683,0.00006226282,0.01994283,0.0007359854,0.9773297,0.001454546,0.00002172169],"study_design_candidate":"theoretical_or_conceptual","study_design_consensus":"theoretical_or_conceptual","genre_codex":"methods","genre_gemma":"empirical","genre_scores_codex":[0.4056623,0.001923707,0.4911713,0.002108541,0.0003759273,0.00006318423,0.00022536,0.0002741446,0.09819555],"genre_scores_gemma":[0.9641524,0.0006362124,0.02886527,0.0001734226,0.0003094174,0.00005184195,0.00008129978,0.0001282105,0.005601858],"genre_candidate":"empirical","genre_consensus":null,"teacher_disagreement_score":0.004904326,"threshold_uncertainty_score":0.01833302,"prediction_status":"machine_predicted_unvalidated"},"machine_scores":{"provisional":true,"baseline":true,"maturity_gate_passed":false,"score_opus":0.03241577720986503,"score_gpt":0.274013580765115,"score_spread":0.24159780355525,"validation_status":"score_only:v0-immature-baseline","note":"Baseline scores from an immature model (maturity gate not passed). Scores rank; they never assert a category."}}