Fundamental constants: is the universe fine tuned for life to exist?

03/15/23 • 41 min

Imagine a universe with extremely strong gravity. Stars would be able to form from very little material. They would be smaller than in our universe and live for a much shorter amount of time. But could life evolve there? It after all took human life billions of years to evolve on Earth under the pleasantly warm rays from the Sun.

Now imagine a universe with extremely weak gravity. Its matter would struggle to clump together to form stars, planets and – ultimately – living beings. It seems we are pretty lucky to have gravity that is just right for life in our universe.

Featuring Fred Adams, professor of physics, University of Michigan, and Paul Davies, professor of physics, Arizona State University.

This episode was presented by Miriam Frankel and produced by Hannah Fisher. Executive producers are Jo Adetunji and Gemma Ware. Social media and platform production by Alice Mason, sound design by Eloise Stevens and music by Neeta Sarl. A transcript is available here. Sign up here for a free daily newsletter from The Conversation.

Further reading:

The multiverse is suspiciously unlikely to exist unless it is one of many

Featuring Fred Adams, professor of physics, University of Michigan, and Paul Davies, professor of physics, Arizona State University.

Further reading:

The multiverse is suspiciously unlikely to exist unless it is one of many

Previous Episode

Is time an illusion?

Without a sense of time, leading us from cradle to grave, our lives would make little sense. But on the most fundamental level, physicists aren't sure whether the sort of time we experience exists at all. We talk to three experts and find out if time could potentially be moving backwards as well as forwards.

Featuring Sean Carroll, Homewood professor of natural philosophy at Johns Hopkins University, Emily Adlam, postdoctoral associate of the philosophy of physics at Western University and Natalia Ares, Royal Society university research fellow at the University of Oxford.

Further reading:

Next Episode

Is there a multiverse?

Interest in the multiverse theory, suggesting that our universe is just one of many, has spiked since the movie Everything Everywhere All At Once was released. The film follows Evelyn Wang on her journey to connect with versions of herself in parallel universes to stop the destruction of the multiverse. The multiverse idea has long been an inspiration for science fiction writers. But does it have any basis in science? And if so, is it a concept we could ever test experimentally?

Featuring Andrew Pontzen, professor of Cosmology at University College London, Katie Mack, Hawking chair in cosmology and science communication at the Perimeter Institute for Theoretical Physics, and Sabine Hossenfelder, research fellow of physics at the Frankfurt Institute for Advanced Studies.

This episode is presented by Miriam Frankel and produced by Hannah Fisher. Executive producers are Jo Adetunji and Gemma Ware. Social media and platform production by Alice Mason, sound design by Eloise Stevens and music by Neeta Sarl. A transcript is available here. Sign up here for a free daily newsletter from The Conversation.

Further reading: