Several years ago, researchers reported an unexpected motion of several galactic clusters towards one area of the universe. The effect, which came to be known as 'dark flow,' has puzzled cosmologists. We'll talk about the mind-boggling idea that stuff we can't see within our visible universe could be causing gravitational effects on visible matter.
We'll also hear about new studies into the fine structure constant -- which some researchers say may not be so constant after all. Can the rules of physics differ from one place to another? Or are indications of a non-constant fine structure constant signs of other new physics yet to be discovered?
Produced by Annette Heist, Senior Producer