Our Antimatter, Mirrored, Time-Reversed Universe

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The foundations of quantum theory rests on its symmetries. For example, it should be impossible to distinguish our universe from one that is that is the perfect mirror opposite in charge, handedness, and the direction of time. But one by one these symmetries were found to be broken, threatening to break all of physics along with them.

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Previous Episode: Why String Theory Is Wrong

Hosted by Matt O'Dowd

Written by Graeme Gossel & Matt O'Dowd

Graphics by Luke Maroldi

Assistant Editing and Sound Design by Linda Huang

In his famous lectures on physics, Richard Feynman talks about what it means to expect the universe to be identical in the mirror. For it to be parity-symmetric. He invites us to imagine a clock in a mirror reflection – numbers are backwards, components are all flipped left to right, and it ticks counterclockwise. And then we imagine building that mirror clock in reality. Everything is constructed as though reflected. Numbers get painted backwards. Every screw with right-handed thread or right-spiraling coil is replaced with a left-handed version. Our intuition tells us that the mirror clock should tick in exactly the same way, except counter-clockwise. Our intuition would be wrong.

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