We all have secrets we want to obscure, from childhood notes between friends to Da Vinci's notebooks,

to the wartime messages famously cracked by Alan Turing and a cohort of English cryptographers.

To share secrets with a friend, an ally, a co-conspirator, there's cryptography, there are codes

and ciphers. Ingenious means to safeguard information against prying eyes. But in lockstep,

there are code breakers, and equally ingenious means to decipher

the hidden information. Cryptography has become crucial to modern life and commerce to protect our

emails, our banks, and our national security. While developing more and more secure encryptions,

researchers have recently made some unexpected

discoveries that reveal deeper truths about the theoretical limits of secrecy itself.

I'm Jan 11, and this is The Joy of Why, a podcast from Quantum Magazine, where I take turns

at the mic with my co-host, Steve Strogatz,

exploring the biggest questions in math and science today. In this episode, Theoretical Computer

Scientist, Boas Barak, demystifies cryptography as we ask, is it possible to perfectly protect secrets?

Boez is the Gordon-McKee Professor of Computer Science at Harvard University.

He's also a member of the Scientific Advisory Board for Quantum Magazine and the

Simons Institute for the Theory of Computing.

His research centers on cryptography, computational complexity, quantum computing, and the foundations of machine learning.

Boas, welcome to the show.

Thank you.

Thank you very much.

So glad to have you.

This is quite a challenging subject.

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