Observations of the cosmos suggest that unseen sources of gravity — dark matter — tug at the stars in galaxies, while another mysterious force — dark energy — drives the universe to expand at an ever-increasing rate. The evidence for both of them, however, hinges on assumptions that gravity works the same way at all scales. What if that’s not true? In this episode, theoretical physicist Claudia de Rham explains her work on an alternative explanation called “massive gravity” to host Janna Levin.

Within just a few years, artificial intelligence systems that sometimes seem to display almost human characteristics have gone from science fiction to apps on your phone. But there’s another AI-influenced frontier that is developing rapidly and remains untamed: robotics. Can the technologies that have helped computers get smarter now bring similar improvements to the robots that will work alongside us? In this episode, Daniela Rus, a pioneering roboticist at the Massachusetts Institute of Technology, talks to host Steven Strogatz about the surprising inspirations from biology that may help robots rise to new levels.

Can you keep a secret? Modern techniques for maintaining the confidentiality of information are based on mathematical problems that are inherently too difficult for anyone to solve without the right hints. Yet what does that mean when quantum computers capable of solving many problems astronomically faster are on the horizon? In this episode, host Janna Levin talks with computer scientist Boaz Barak about the cryptographic techniques that keep information confidential, and why “security through mathematics” beats “security through obscurity.”

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