Let’s explore how constant this speed of light fundamental constant really is.

What If The Speed of Light is Not Constant? PBS Space Time

Premiered July 19, 2023
What If The Speed of Light is Not Constant?

One of the most fundamental physics facts is that the speed of light in a vacuum is constant for all observers. But can we really be sure? In fact, variable speed of light theories have long been used to try to explain everything from dark energy to gravity itself. Let’s explore how constant this fundamental constant really is.

About the Program

PBS Space Time

PBS Space Time explores the outer reaches of space, the craziness of astrophysics, the possibilities of sci-fi, and anything else you can think of beyond Planet Earth. Host Matt O'Dowd breaks down both the basic and incredibly complex sides of space and time.

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