For decades, astronomers have been trying to nail down the value of the Hubble constant—a measure of how fast the universe is expanding. But some cosmologists say there’s evidence that the universe is expanding faster than physics can explain, and our current models of it might be broken. Hosts Flora Lichtman and Ira Flatow talk with Wendy Freedman and Dan Scolnic, two cosmologists with different takes on this constant controversy.

Guests: 
Wendy Freedman, a former team leader of the Hubble Key Project, is a professor of astronomy and astrophysics at the University of Chicago in Chicago, Illinois.
Dr. Dan Scolnic is a cosmologist and associate professor of physics at Duke University in North Carolina.

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