We hear two stories of everyday life which are more easily understood if one knows some of the laws of physics, specifically the Mediocrity Principle and the Casimir Effect.

If there is intelligent life elsewhere in the universe, why haven’t we heard from the extraterrestrials yet? Producer David Kestenbaum explains The Fermi Paradox to host Ira Glass. The possibility that we are alone in the universe makes David sad.

Senior Editor David Kestenbaum talks with a different kind of advocacy group: animal scientists doing their best to save a particular species before it winks out of existence. (16 minutes)

Producer David Kestenbaum tells the story of an astronaut who returns with a very unexpected view of the great beyond.

Producer David Kestenbaum took issue with the entire premise of today’s show, and explains why.

David Kestenbaum tells the story of a man on the verge of one of the greatest scientific discoveries of all time … right on the verge. (4 minutes) 

Guest host David Kestenbaum talks to producer Diane Wu about a list she keeps of things she means to know. Sweet potatoes vs. yams.

David Kestenbaum desperately wants to set the record straight for everybody about whether aliens regularly visit earth. They don’t, he says.

David’s story continues. He visits his old physics professor, who helps him figure out what to think.

David Kestenbaum tells Ira about the time, when he was doing graduate work in physics, he and his other single friends decided to figure out the mathematical probability that they’d find girlfriends. They wanted to know what the chances were that there was more than one person in the world for them.

NPR reporter David Kestenbaum tells host Ira Glass about the time, when he was doing graduate work in physics, he and his other single friends decided to figure out the mathematical probability that they'd find girlfriends. They wanted to know what the chances were that there was more than one person in the world for them.