Episode 83: Dark matter and dark energy

Episode 83: Dark matter and dark energy

Author: Tom Chivers and Stuart Ritchie September 9, 2025 Duration: 56:41

Where is most of the universe? And why don't we know yet? Yes—we’re talking about dark matter and dark energy, the mysterious stuff that’s predicted by physical theory, but which still remains elusive in experiments.

After speaking to an actual physicist, Tom and Stuart attempt to explain what dark matter and dark energy are supposed to be, and what physicists would have to see in their experiments to know that they exist. They also come down with a serious case of physics envy.

The Studies Show is sponsored by Works in Progress magazine, which has just published this excellent new article on the history of French nuclear power. Why has France been so successful at building nuclear plants while other countries have dropped the (radioactive, probably flourescent green) ball? “Liberté, Egalité, Radioactivité” tells you everything you need to know. Find it and much more, all for free, at worksinprogress.co.

Show notes

* August 2025 Science article about a “big blob” of dark matter in the Milky Way

* LIGHTS ALL ASKEW IN THE HEAVENS

* Cosmic microwave background? Or pigeon droppings?

* 1984 Nature paper about “cold dark matter” and the formation of galaxies

* WMAP probe map of the cosmic microwave background

* Two papers from 1998 on the accelerating expansion of the universe

Credits

We’re very grateful to Prof. Andrew Pontzen of Durham University for talking to us for this episode (all mistakes are our own). The Studies Show is produced by Julian Mayers at Yada Yada Productions.



This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit sciencefictionspod.substack.com/subscribe

Every week, Tom Chivers and Stuart Ritchie pull apart the biggest arguments and most confusing claims making headlines. Science Fictions isn't just about celebrating breakthroughs; it's a necessary dive into the messy, contested, and often surprising realities of how science actually works. You'll hear them unpack heated debates, examine questionable studies, and explore why even solid research can sometimes lead to public confusion. This podcast serves as a guide through the noise, separating compelling evidence from overblown narratives. Each episode feels like a conversation with two deeply informed friends who aren't afraid to ask tough questions, offering clarity on topics that matter. For anyone curious about the stories behind the science headlines, this is an essential listen. Tune in for thoughtful analysis that goes beyond the press release, grounded in a genuine fascination with how we know what we know.
Author: Language: English Episodes: 50

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