{"schema":"https://ver.cy/schemas/card/1.0.0","id":"vr.tr.dark-matter-halo","code":"thing-q864952","url":"https://ver.cy/models/thing/q864952/","name":"dark matter halo","alternateNames":[],"kind":"thing","status":"published","version":"0.2.0-wave.1","language":"en","classifiers":{"family":"Thing Registry","category":"Physical world and living systems","entryKind":"thing","plane":"PHY","domain":["PHY.SPC"],"industry":[],"navPath":"","tags":[],"facets":{}},"whatItIs":"A hypothesised, roughly spherical halo of dark matter surrounding galaxies and galaxy clusters, extending far beyond their visible matter and inferred from galaxy rotation curves, gravitational lensing and cosmological simulations; halos are central to the standard Lambda-CDM model, while alternatives such as modified gravity are debated and dark matter has not been directly detected.","purpose":"Let an agent explain dark matter halos by evidence, models, profiles and open questions, attributing competing interpretations.","scope":{"in":[],"out":[],"boundaries":[]},"distinguishingFeatures":["Invisible matter distribution","Extends beyond visible galaxy","Inferred through gravity","Central to standard cosmology"],"structure":{"bundles":[{"id":"evidence","name":"Evidence","description":"Why halos are inferred.","layers":[{"id":"rotation","name":"Rotation","description":"Rotation curves.","findings":[{"id":"rotation-finding","name":"Rotation","description":"Rotation curves.","questions":[{"text":"How do flat rotation curves suggest dark matter halos?","kind":"definition"},{"text":"Which observations are key?","kind":"provenance"}]}]},{"id":"lensing","name":"Lensing","description":"Gravitational lensing.","findings":[{"id":"lensing-finding","name":"Lensing","description":"Lensing evidence.","questions":[{"text":"How does lensing map mass in halos?","kind":"definition"},{"text":"What did observations of colliding clusters show, according to astronomers?","kind":"provenance"}]}]}]},{"id":"models","name":"Models","description":"Structure.","layers":[{"id":"profiles","name":"Profiles","description":"Density profiles.","findings":[{"id":"profiles-finding","name":"Profiles","description":"Density profiles.","questions":[{"text":"What do NFW and cored profiles describe, and which fits this galaxy?","kind":"definition"},{"text":"What is the cusp-core problem?","kind":"provenance"}]}]},{"id":"simulations","name":"Simulations","description":"Cosmological simulations.","findings":[{"id":"simulations-finding","name":"Simulations","description":"Simulations.","questions":[{"text":"What do simulations predict about halo formation and subhalos?","kind":"provenance"},{"text":"How well do they match observations?","kind":"boundary"}]}]}]},{"id":"debate","name":"Debate","description":"Alternatives.","layers":[{"id":"alternatives","name":"Alternatives","description":"Modified gravity.","findings":[{"id":"alternatives-finding","name":"Alternatives","description":"Alternatives.","questions":[{"text":"How do modified gravity theories such as MOND explain the same observations, according to proponents and critics?","kind":"provenance"},{"text":"Which evidence challenges each view?","kind":"provenance"}]}]},{"id":"detection","name":"Detection","description":"Direct detection.","findings":[{"id":"detection-finding","name":"Detection","description":"Direct detection.","questions":[{"text":"Has dark matter been directly detected, according to experiments?","kind":"provenance"},{"text":"Which candidates are being tested?","kind":"provenance"}]}]}]},{"id":"learning","name":"Learning","description":"Explaining.","layers":[{"id":"explain","name":"Explain","description":"Plain language.","findings":[{"id":"explain-finding","name":"Explain","description":"Plain explanation.","questions":[{"text":"How can dark matter halos be explained simply and accurately?","kind":"action"},{"text":"Which caveats must be included?","kind":"boundary"}]}]},{"id":"senses","name":"Senses","description":"Disambiguation.","findings":[{"id":"senses-finding","name":"Senses","description":"Other halos.","questions":[{"text":"Is an optical halo or a stellar halo meant instead?","kind":"boundary"},{"text":"Which entry fits?","kind":"action"}]}]}]}]},"agentConduct":{"may":["Explain the evidence for dark matter halos and the alternatives, attributing each.","Report halo properties from published models and simulations, with their assumptions."],"mustNot":["Present dark matter as directly detected.","Dismiss alternative theories such as modified gravity without stating the evidence.","Present simulation results as observations."],"requiresHuman":["Publishing a claimed detection of dark matter."]},"ethics":{"considerations":["Scientific honesty requires stating that dark matter is inferred, not observed directly.","Large research investments depend on fair representation of competing theories."],"affectedParties":["The public and students","Researchers in competing fields"]},"owners":{"steward":"Nobody: a hypothesised structure; the scientific community answers for its models.","roles":[],"masterSystems":[]},"relations":[{"target":"Q5961257","type":"parent","note":"registry parent class"},{"target":"hypothetical astronomical object","type":"related","note":"category"},{"target":"dark matter","type":"related","note":"component"},{"target":"gravitational lensing","type":"related","note":"evidence"},{"target":"modified gravity theories","type":"related","note":"alternative"}],"interaction":{"identity":{"applicability":"required","items":["Vercy registry: vr.tr.dark-matter-halo","Wikidata: Q864952 (https://www.wikidata.org/wiki/Q864952)"]},"properties":{"applicability":"required","items":["Enclosed halo mass:  solar masses - Inferred within a stated radius from gravitational effects under an explicitly identified model.","Halo radius:  kiloparsecs - Inferred using a stated boundary convention because the halo has no directly observed sharp edge.","Dark matter density:  solar masses per cubic parsec - Inferred as a function of distance from the centre by fitting a density profile to gravitational observations.","Halo axis ratio:  dimensionless - Estimated from gravitational constraints or simulations with the compared axes and modelling assumptions stated."]},"recognition":{"applicability":"required","items":["Flat galaxy rotation curves","Weak and strong lensing maps","Stellar halos are made of stars","Invisible; mapped indirectly from motions of stars and gas and from lensing."]},"capabilities":{"applicability":"required","items":["explain the evidence for dark matter halos","describe halo density profiles","summarise alternative theories with attribution","find simulation and survey data"]},"hazards":{"applicability":"required","items":["Presenting dark matter as directly detected","Dismissing alternatives without attribution","Confusing halos with optical halos"]},"interfaces":{"applicability":"required","items":["No specific regulation"]},"context":{"applicability":"required","items":["Cosmology and galaxy formation.","galaxy halos","cluster halos","subhalos","NFW and cored profiles","simulated halos"]}},"sources":[{"title":"Wikidata item Q864952: dark matter halo","url":"https://www.wikidata.org/wiki/Q864952","note":"identity and sense of the item"},{"title":"Wikipedia: Dark matter halo","url":"https://en.wikipedia.org/wiki/Dark_matter_halo","note":"general description of the item"}],"openQuestions":["Should profiles be separate entries?","How should simulations be linked?","How should detection experiments be linked?"],"resources":{"spec":"/models/things/publications/thing-q864952/spec.json"},"provenance":{"origin":"thing registry research (pass 2)","builtFrom":["models/things/publications/thing-q864952/spec.json"],"providers":["Claude"],"researchStatus":"unreviewed","generatedAt":"2026-09-11T14:17:01Z","builder":"tools/build_cards.py@1.0.0"},"completeness":{"sections":{"classifiers":"filled","whatItIs":"filled","purpose":"filled","distinguishingFeatures":"filled","structure":"filled","agentConduct":"filled","ethics":"filled","owners":"filled","relations":"filled","interaction.identity":"filled","interaction.properties":"filled","interaction.recognition":"filled","interaction.capabilities":"filled","interaction.hazards":"filled","interaction.interfaces":"filled","interaction.context":"filled","sources":"filled"},"notes":{"_gate":"Published through the thing publication gate 1.0 on 2026-10-07T10:10:33+00:00: completeness 1.00; sense: Wikidata description; 2 live sources; review by codex: pass"},"score":1.0}}