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#

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.

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!

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

Einstein’s field equations (with cosmological constant) in fully expanded form. Gμν + Λgμν = 8πG/c⁴ Tμν The large panel below shows the complete coordinate expansion of the Einstein tensor Gμν expressed entirely in terms of the metric tensor gαβ and its first- and second-order partial derivatives - the explicit differential equations at the heart of general relativity.

This is one of the most emotionally devastating images in modern science fiction. People don't realize this scene is real physics. Cooper ages four years. His daughter ages 89. Not because of magic. Not because of artistic license. Because of gravity. Time runs slower near massive objects. A planet near a black hole experiences time at a different speed than Earth does. One hour on Miller's planet is seven years on Earth. Christopher Nolan didn't invent this. Albert Einstein did. In 1915. And the math has been confirmed ever since. The most heartbreaking scene in modern science fiction is just general relativity, told as a love story.

Bernhard Riemann’s 1854 breakthrough proved that geometry isn't just about flat planes: it’s about the intrinsic curvature of space itself. This image perfectly breaks down the three fundamental geometries that govern our universe: > Zero Curvature (Euclidean): The classic flat plane. Parallel lines never meet, and triangle angles sum exactly to 180°. > Positive Curvature (Elliptical): Think of a sphere. Lines eventually intersect, and triangles "bulge," exceeding 180°. > Negative Curvature (Hyperbolic): A saddle-like surface where lines diverge rapidly, and triangle angles sum to less than 180°. By treating these surfaces as "manifolds," Riemann provided the mathematical framework that Albert Einstein later used to describe the warping of spacetime in General Relativity.