Time is an illusion, and these physicists say they know how it works [video](youtube.com)99 points by lisper 2 years ago | 65 comments
NASA's Future SLS Booster Failed Its First Test [video](youtube.com)3 points by perihelions 1 year ago | 0 comments
Paul A. M. Dirac, Interview by Friedrich Hund (1982) [video](youtube.com)106 points by mdp2021 1 year ago | 24 comments
I Built a Mechanical Calculator [video](youtube.com)81 points by lispybanana 1 year ago | 21 comments
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