General Relativity Keeps Revealing Unexpected Spacetime Geometries That Go Far Beyond Everyday Intuition. In 1988, Kip Thorne and Michael Morris described a traversable Wormhole geometry that strangely connects two distant regions of Spacetime without an event horizon or central singularity. No traversable Wormhole has ever been observed. Within General Relativity, though, these solutions are mathematically valid if Spacetime is supported by exotic stress-energy that violates classical energy conditions. It's a solution Einstein’s field equations allow, but nature has not confirmed. #Einstein# #GeneralRelativity# #Wormholes# #Spacetime# #Physics# #Relativity#

Albert Einstein taught relativity at Lincoln University in 1946. The class was entirely African American at a time when racism was widespread in academia. Einstein supported these students and spoke openly against segregation, calling it a disease. For science, there are no human races—only human beings.

Einstein and David Hilbert independently pursued General Relativity. Einstein relied on physical intuition and thought experiments, while Hilbert used rigorous mathematics and advanced geometry. Einstein reached the final theory first, and Hilbert accepted it graciously. Hilbert’s efforts also led to Emmy Noether’s work, producing Noether’s Theorem—one of the deepest foundations of modern physics.

Dirac wrote it in 1928 so an electron could obey both quantum mechanics and special relativity; the γ matrices mix the components precisely as Lorentz transformations demand, while the mass term couples the two chiralities. A first-order equation for a four-component spinor that simultaneously carries energy, momentum, spin and the seed of antimatter. Gauged, the same compact line becomes the starting point of quantum electrodynamics and, with the appropriate internal symmetries, of the weak and strong interactions as well.

Adam Brown (@A_G_I_Joe) 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 the video below, 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. 0:00:00 – The coincidence that led Einstein to general relativity 0:16:42 – Gravity is a consequence of curved spacetime, not a force 0:31:46 – Why black holes prevent unlimited energy extraction 0:47:12 – Black holes are the ultimate power plants 1:13:50 – What falling into a black hole would actually feel like 1:18:51 – The three ways we know black holes are real 1:24:21 – The first time we saw gravity bend light 1:29:33 – How far can AI get without experimental evidence? Look up Dwarkesh Podcast on YouTube/Spotify to watch. Enjoy!

excited for Starship and the leap in reducing cost to reach orbit. @elonmusk led the way even more excited about companies expanding the opportunity to reach orbit for others as SpaceX will broadly reserve their capacity for themselves @relativityspace @stoke_space who else?

Your phone’s GPS works partly because Einstein was right about time. GPS satellites carry atomic clocks. Because they move quickly, relativity makes their clocks tick about 7 microseconds slower per day than clocks on Earth. But because they experience weaker gravity in orbit, their clocks tick about 45 microseconds faster. Net effect 38 microseconds per day. That sounds microscopic. It isn’t. Without correcting for it, GPS positioning errors would accumulate by roughly 10 kilometers per day. The remarkable part is what this says about systems built on measurement. A tiny error in something nobody notices can become enormous when repeated across a complex system. Markets have the same property. A timestamp slightly wrong. A price feed slightly delayed. A corporate action applied incorrectly. A tiny data error repeated millions of times. The individual error looks harmless. The system doesn’t care how small it was. Small errors become large when the system gives them enough time to compound. #Trading# #QuantFinance# #MarketData# #SystemsThinking#

FULL INTERVIEW: Yong Zheng-Xin says a paper argued LLMs can't make Einstein-style leaps, so they'll never reach general relativity. His answer: Feynman showed you can derive it without Einstein, from theories that already existed. @yong_zhengxin works at @OpenAI on RSI preparedness and safety. 2 weeks after publishing "Hot Take: LLMs Can Jump," he joined @theojaffee and @schisofrenia to discuss whether models can create genuinely new knowledge: 01:18 the 3 kinds of reasoning, and which one the paper says LLMs lack 03:07 why cyber is accelerating and algorithmic progress isn't 05:48 the elevator thought experiment, and what Feynman said about it 07:59 why a model that isn't a specialist finds connections specialists miss 08:45 Yudkowsky's Bayesian superintelligence and three frames of a falling apple 10:59 why interconnected knowledge makes continual learning easier 14:08 the wet lab is the bottleneck, not the reasoning 15:31 whether you need embodiment to know when something feels wrong 17:24 the real constraint on abduction is diversity of hypotheses 19:22 we never ask one scientist to make every breakthrough 22:09 whether GPT-4 could do today's cyber work with infinite compute 23:34 what safety even means once a model is improving itself