Up Next
Back to Show
PBS Space Time
What If The Speed of Light is Not Constant?
Season 9
Episode 19
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.
Support Provided By
15:14
Is Dark Energy Getting Weaker?
16:08
Here’s the story we like to tell about the beginning of the universe.
17:44
We’ve never seen a TDE in the Milky Way, but we’ve seen them in distant galaxies.
16:51
Let’s talk about quantum gravity experiments that can be done here on Earth!
19:25
What if gravity isn’t weirdly quantum at all, but rather … just a bit messy?
17:02
Have we reached the end of the line of discoverable elements?
15:32
Can we change the color of a black hole?
18:26
Learn about Nobel laureate Roger Penrose's idea of how consciousness is caused by quantum processes.
16:28
Faster than light travel may produce gravitational waves that we could see here on Earth.
20:07
All particles belong to two large groups: fermions and bosons.
16:11
Just how much stronger is this year’s solar activity going to get?
17:25
So you’ve decided to jump into a black hole...