The End of Dark Matter? – Dr. Jenny Wagner, DemystifySci +431

Physicist Jenny Wagner joins us, asking not whether dark matter is possible but whether it is necessary, whether the missing mass was ever missing or only misplaced inside the models we carried in before we looked up. She works the inverse problem of gravitational lensing the way a person works a locked door in the dark, feeling for what the data actually says against what the assumptions quietly whisper, until the cosmological constant, dark energy, and the whole dark sector start to look less like discoveries and more like scaffolding we forgot was scaffolding. From Zwicky and the Coma cluster to MOND and the Bullet cluster, she traces how a pragmatic guess hardened into orthodoxy, and how general relativity alone might carry more of the weight than anyone budgeted for. Cosmology as it should be done, grounded in what the sky gives us and honest about what it withholds. Jenny's blog: https://thegravitygrinch.blogspot.com/ PATREON   / demystifysci   PARADOX LOST PRE-SALE: https://buy.stripe.com/7sY7sKdoN5d29e... HOMEBREW MUSIC - Check out our new album! Hard Copies (Vinyl): FREE SHIPPING https://demystifysci-shop.fourthwall.... Streaming: https://secretaryofnature.bandcamp.co... PARADIGM DRIFT https://demystifysci.com/paradigm-dri... 00:00 Go! Grounding Cosmology in What We Can Actually Observe 00:01:57 Data First: Separating Physics from Statistical Assumptions 00:09:32 How Dark Matter Falls Out of the Models We Choose 00:14:38 Zwicky, Coma, and the Birth of the Missing Mass Problem 00:20:58 Bound or Just Passing Through? The Cluster Stability Debate 00:25:22 Two Missing Mass Problems Merge Into One Story 00:33:40 Lambda: The Cosmological Constant and the Rise of Dark Energy 00:45:09 Why Simple Models Stuck, and the Underdetermination Trap 00:52:04 Average Density and the Roots of Statistical Cosmology 01:01:05 Where Cosmology and Astrophysics Split 01:09:12 Causality From Inside the Universe 01:18:21 One Snapshot of the Cosmos, and What Webb Adds 01:24:48 Where the Dark Matter Doubt Began: Lensing's Fine Print 01:32:20 Meeting MOND and the Bullet Cluster Up Close 01:39:24 Revisiting General Relativity at Galactic Scales 01:44:49 Gravity as Geometry, and the Cause We Still Can't Name 01:51:15 The Case for Cosmology Without a Dark Sector 01:56:21 Why Equations Take Their Form: Higgs vs. Dark Matter 02:03:52 Necessary or Merely Sufficient? Bias in the Field 02:08:23 Storytelling, Awe, and the Pull of Exotic Explanations 02:13:39 Determinism, Free Will, and the Limits of Reductionism 02:20:07 What's Next: Curvature, and the Gravity Grinch #DarkMatter #Cosmology #GravitationalLensing #DarkEnergy #Astrophysics #GeneralRelativity #Physics #Spacetime #Gravity MERCH: Rock some DemystifySci gear : https://demystifysci-shop.fourthwall.... AMAZON: Do your shopping through this link: https://amzn.to/3YyoT98 DONATE: https://bit.ly/3wkPqaD SUBSTACK: https://substack.com/@UCqV4_7i9h1_V7h... RSS: https://anchor.fm/s/2be66934/podcast/rss MAILING LIST: https://bit.ly/3v3kz2S SOCIAL: Discord:   / discord   Facebook:   / demystifysci   Instagram:   / demystifysci   Twitter:   / demystifysci   MUSIC: -Shilo Delay: https://g.co/kgs/oty671