Adam Brown – A deep but accessible introduction to general relativity
Adam Brown is back!
General relativity is said to be the most beautiful idea the human mind has ever produced. Most of us will never get to fully appreciate its elegance by taking the 20-lecture graduate course Adam taught on it at Stanford. But in this episode, Adam distills the key idea at its heart so clearly and compellingly that even I could keep up lol.
At the core of general relativity, Einstein is trying to figure out the principle behind a particular coincidence: that the mass that resists acceleration and the mass that gravity pulls on just happen to be exactly the same. Adam then leads us through the path of insight which Einstein called his “happiest thought.”
Then Adam lectures on black holes. First, by showing how even under special relativity you could create a perpetual motion machine if black holes weren’t truly black. And then, by explaining why the observations of an infalling observer and a distant bystander to the black hole would be so radically different
Adam leads Blueshift, the team at Google DeepMind cracking science and reasoning, which gave us the opportunity to discuss at the very end how close we are to AIs that could rediscover general relativity from scratch. Stay till the close for some philosophy of science.
Watch on YouTube; read the transcript.
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Timestamps
(00:00:00) – The coincidence that led Einstein to general relativity
(00:16:42) – Gravity is a consequence of curved spacetime, not a force
(00:31:46) – Why black holes prevent unlimited energy extraction
(00:47:12) – Black holes are the ultimate power plants
(01:13:50) – What falling into a black hole would actually feel like
(01:18:51) – The three ways we know black holes are real
(01:24:21) – The first time we saw gravity bend light
(01:29:33) – How far can AI get without experimental evidence?
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