A person shine a torch and showing light waves with two females looking puzzled
Podcast, 27 mins

Aether: Speaking of Nothing

What is light? Discover how this question led to a paradigm shift in physics - needing both quantum theory and relativity to answer it in full.

Water waves are movements in water, so light waves are movements in… aether.

At least that was the leading theory in the 18th century. Sounds simple enough but nailing down what this aether is leads to curious properties. In truth light waves are quite different from water waves in many respects including that their speed is constant no matter how fast you yourself are going.

The history of aether theory is tied to the emergence of both quantum theory and relativity. It records how scientists struggled to let go of their intuition and see the reality of space and time in a new light. Join us on our mission to understand the true nature of light and listen to this week’s episode of Good in Theory.

Credits

  • Created and Produced by: Rita Neves (Research Associate at the University of Sheffield)
  • Created and Produced by: Sofie Ried (PhD Student at the University of Sheffield)
  • Intro/Outro Music: Andrew Glover
Correct as of content publication - 22/01/2026

See also