Cosmology podcasts

Physicist Daniel Akerib joins Sean Carroll to examine the search for weakly interacting massive particles and the challenges of directly detecting dark matter. They discuss a single unusual event in recent LUX-ZEPLIN data and why its low statistical significance warrants interest rather than a discovery claim. The conversation connects this result with Akerib’s experience in the Cryogenic Dark Matter Search, LUX and LUX-ZEPLIN experiments.

Hosted by Sean Carroll

This episode explores transient searches, multiprobe cosmology and planetary nebulae through conversations with researchers at Jodrell Bank. Alex Reeves discusses his doctoral research, the computational methods used in multiprobe cosmology and his experience as a PhD student. Alec Csukai reflects on completing a doctorate in planetary-nebula research and the transition beyond graduate study. The presenters also discuss experiences of the August solar eclipse and share highlights from the Jodcast’s twentieth-birthday outreach activities at the National Astronomy Meeting. The episode combines current astrophysics with research-career perspectives and public engagement.

Hosted by Phoebe Ryder, Louisa Mason

Astrophysicist Benoît Famaey and theoretical physicist Francesca Calore discuss the evidence motivating dark matter and the challenges of identifying its nature. With Alexandra Delbot, they examine proposed particle candidates, possible detection signals and why a promising observation requires careful scrutiny before being treated as a discovery.

Hosted by Alexandra Delbot

Fraser Cain and Pamela L. Gay examine possible futures of the universe across vastly different timescales. Topics include the Milky Way and Andromeda, cosmic isolation as expansion continues, the fading microwave background, the end of star formation and the era of stellar remnants. They discuss uncertain processes such as proton decay, black-hole evaporation through Hawking radiation, entropy and heat death, alongside alternative outcomes if dark energy evolves. These are model-dependent projections. Pamela Gay is a senior scientist at the Planetary Science Institute. Published on 21 September 2026, the episode appears in the feed as The Beginning and End of Everything, Part 2. Its original duration is 37 minutes 7 seconds.

Hosted by Fraser Cain, Pamela L. Gay

Theoretical physicist Jonathan Halliwell joins Steven Strogatz and Janna Levin to discuss how quantum decoherence helps explain the transition from wave-like quantum systems to the classical macroscopic world. The conversation covers quantum cosmology, decoherent histories, the measurement problem, macroscopic realism and why the quantum-to-classical transition does not require a conscious observer.

Hosted by Steven Strogatz, Janna Levin

Fraser Cain and Pamela L. Gay explore what cosmology can establish about the universe’s earliest history and where knowledge remains limited. The discussion covers inflation, the separation of forces, the emergence of particles and nuclei, and density fluctuations that seed later structure. Recombination and the cosmic microwave background lead into the dark ages, the first stars and reionization, with observations including JWST helping test models of the early universe. Pamela Gay is a senior scientist at the Planetary Science Institute. This Astronomy Cast episode was published on 14 September 2026; its publisher feed labels it The Beginning and End of Everything, Part 1. The original duration is 39 minutes 27 seconds.

Hosted by Fraser Cain, Pamela L. Gay

Jim Al-Khalili and Sean Carroll discuss the nature of time, whether it is fundamental or emergent, and how its direction relates to physical laws and human experience. Their conversation connects the arrow of time with unresolved questions in quantum mechanics, biology and cosmology.

Hosted by Sean Carroll

Øystein Elgarøy and Anders Kvellestad discuss unresolved problems in physics, drawing on cosmology and particle physics. Conversation in Norwegian.

Adam Riess explains how astronomers measure the universe's expansion and why different methods give conflicting results. He revisits the evidence for accelerated expansion and examines what the Hubble tension might reveal about measurement techniques or missing ingredients in cosmological models.

Hosted by Steven Strogatz

Interviews with Seshadri Nadathur and Maggie Lieu cover cosmological tensions, DESI observations, galaxy clusters and machine learning. Reports from the Euclid-UK and LSST:UK meetings add perspectives on major surveys and the future of observational cosmology.

Sean Carroll explores explanations for cosmic acceleration beyond a constant vacuum energy. He discusses dynamical dark-energy models, their relationship to particle physics, possible changes to gravity and the observations that could help distinguish competing theories.

Hosted by Sean Carroll

Sean Carroll traces the cosmological constant from Einstein's equations to modern evidence for accelerated expansion. He explains why the energy of empty space is difficult to reconcile with particle physics and examines the related puzzles of its observed size and importance in today's universe.

Hosted by Sean Carroll

Harry Bevins discusses REACH, a South African global 21-centimetre experiment, and the proposed lunar-orbit Cosmocube mission. Claire Davies discusses academic experience, while Soheb Mandhai describes simulation research and postdoctoral work at Manchester.

Daniel Harlow discusses what attempts to reconcile gravity and quantum mechanics reveal about quantum theory itself. The conversation follows black-hole radiation, information loss, the wave function of the universe, the AdS/CFT correspondence and quantum information. It then connects these developments to quantum cosmology and questions about the structure of quantum mechanics.

Hosted by Sean Carroll

Øystein Elgarøy discusses what cosmology can say about conditions preceding the conventional Big Bang account. Conversation in Norwegian.

Thomas Hertog discusses his work with Stephen Hawking on the origin of the Universe and a proposal in which physical laws develop alongside cosmic history. The conversation with Janna Levin examines the role of observers, the limits of multiverse explanations and how the conditions compatible with life might emerge. The proposed framework is discussed as a theoretical approach to unresolved questions.

Hosted by Janna Levin, Steven Strogatz

Cumrun Vafa discusses the gap between string theory's mathematical possibilities and experimental tests. The conversation considers the landscape of candidate universes, the swampland programme for ruling out inconsistent possibilities, dimensional constraints and the role of cosmological observations in seeking predictions relevant to our Universe.

Hosted by Janna Levin, Steven Strogatz

Øyvind Grøn discusses conflicting measurements of the universe's expansion rate and the questions raised by the Hubble tension. Conversation in Norwegian.

Jostein Riiser Kristiansen discusses the observational evidence for dark matter and dark energy and the questions they leave unresolved. Conversation in Norwegian.

Øystein Elgarøy discusses the anthropic principle, apparent fine-tuning of physical laws and proposals involving multiple universes. Conversation in Norwegian.