On the cover of tomorrow's issue of Nature: predicting with high precision what happens when two black holes scatter.

https://www.nature.com/nature/volumes/641/issues/8063

Unifying general relativity and the electromagnetic force? (I presume this also includes the weak nuclear force at sufficiently high energies, but this summary doesn't say)

https://phys.org/news/2025-04-einstein-field-theory.html

I'm pretty much at the limit of my understanding of field theories and such just in this summary article, I don't think I'll even try their full journal article.

@cenobyte - Does Professor Skye or her research assistant have any comment on the matter?

Whooooaaaa! The new #JWST image is so good! So much physics going on — physics Einstein himself thought about!

This is called an Einstein Ring. When a massive foreground galaxy (in this case, an elliptical galaxy) warps the space-time around it, light from behind it bends in our direction.

The JWST caught this fantastic example, where the background spiral galaxy is getting warped into our view. It appears as a ring, but we can see its structures like its spiral arms, gas features and star clusters.

Incredible science happening here!

ESA/Webb/NASA/CSA/G. Mahler

I added the annotations in the second image.

Here we observe Einstein’s theories in action. Time dilation occurs in the faster iPhone due to its accelerated CPU.

You Are Already Traveling at the Speed of Light - Science fiction authors and readers dream of travelling at the speed of light, but... - https://hackaday.com/2025/03/10/you-are-already-traveling-at-the-speed-of-light/ #generalrelativity #science #physics

Testing quantum gravity in the lab:
#quantumphysics #quantummechanics #gravity #generalrelativity #model #research #science

https://phys.org/news/2024-09-theoretical-physicists-method-central-theory.html

Mathematicians Attempt to Glimpse Past the Big Bang
https://www.quantamagazine.org/mathematicians-attempt-to-glimpse-past-the-big-bang-20240531/ BigBang #BlackHoles #GeneralRelativity #geometry #gravity #inflation #mathematics #physics

There's singularities and singularities.

Mathematicians Attempt to Glimpse Past the Big Bang | Quanta Magazine https://www.quantamagazine.org/mathematicians-attempt-to-glimpse-past-the-big-bang-20240531/

New warp drive concept does twist space, doesn’t move us very fast - Enlarge / The Enterprise, caught in the wake of a temporal vortex, witn... - https://arstechnica.com/?p=2025766 #fasterthanlighttravel #generalrelativity #warpdrive #science #physics

“What would you ask Albert Einstein if he were alive today?”

There are many questions, but these are among the first ones that come to mind.

Dr. (and #pilot) #KatieMack on how a #SolarEclipse more than a century ago helped to prove that #Einstein's theory of #GeneralRelativity was (mostly?) correct.

#link: https://www.sciencefocus.com/comment/solar-eclipse-deeper-into-universe

More of Dr. Mack's articles:
#link: https://www.sciencefocus.com/author/dr-katie-mack

I keep seeing the news about lunar time presented as “the Moon is getting its own time zone." What's actually happening is the Moon is getting its own time *standard*. The problem being solved is that time passes slightly more quickly on the Moon compared to Earth (due to General Relativity) and so the Moon needs its own time standard for precise measurements and navigation. UTC is the time standard for measuring time on Earth, and LTC is being created for the Moon.

I had the privilege to open a #science, #history and #arts black hole exhibition in #Boerhaave #Museum in Leiden. You find drawings from #Escher, a telegram from Lorentz informing Einstein of the Eddington expedition that proved him correct, original Penrose diagrams, and, of course, our picture of a black hole.

Astrophysicist 'Fixes' General Relativity by Throwing Out a Major Law
https://www.sciencealert.com/astrophysicist-fixes-general-relativity-by-throwing-out-a-major-law #astrophysics #GeneralRelativity #Renormalization

A new approach for reconciling general relativity and quantum mechanics proposes adding some randomness in general relativity, making it less deterministic on small scales.

For several decades, physicists have been trying to reconcile general relativity and quantum mechanics. These theories, despite each having been empirically validated to several decimal places, contradict each other. The problem is those contradictions seem to happen in places not conducive to empirical investigation, such as black holes or the early universe.

Most of the approaches to solving this try to quantize general relativity, in essence to find a theory of quantum gravity. This is what string theories and loop quantum gravity try to do. And there are others trying to “build up” to gravity and spacetime from quantum entanglement. But these approaches, and others, all seem to have their problems.

The new proposal is to keep spacetime smooth and continuous, but introduce some random wobbles into it. It’s an interesting idea, one which may be testable in the near future. Most physicists seem skeptical, but the ones I’ve read so far seem onboard with at least testing for it.

If the idea turned out to be right, it wouldn’t be a case where general relativity, or classical physics overall, “won”, since GR would end up needing modifications. One thing I wonder is whether scientists would be tempted to regard randomness in GR as fundamental the same way many do for quantum physics. Or would it be seen as a new mystery to be solved?

I personally would see it as a mystery. But I’m saying that as someone whose intuition is that reality is ultimately deterministic. And that when we have a scientific theory with randomness in it, we need an explanation for that randomness.

But we might end up in a situation like quantum physics, where there are different “interpretations” on what’s going on. Many people like the idea of randomness being fundamental. Just as with QM, they might be more inclined to dig in and say that the wobbles are just the way things are. People like me would be left holding out for additional data, or at least new theoretical breakthroughs, to map that randomness back to something more mechanistic.

Incidentally, related to the previous post, it seems likely this would have implications for the many-worlds interpretation. That theory is usually seen as needing spacetime to be quantized. If it turned out, once and for all, that spacetime can’t, many-worlds might be falsified. Given Carlos Rovelli’s 5000:1 bet with the proposing theoretician Johnathan Oppenheim, I suspect it would present issues for relational quantum mechanics as well. Just a reminder that many interpretations of QM aren’t just academic philosophies, but scientific theories in an of themselves.

But it’s also a reminder that no scientific theory can ever be confidently taken as the final word. New data can always dethrone a reigning theory. And that there remains value in continuing to stress test the fundamental structure of even the most successful theories.

What do you think? Would you welcome some randomness in your general relativity? Or like me, would you regard it as a new problem to be solved?

https://selfawarepatterns.com/2023/12/09/what-would-randomness-in-general-relativity-mean/

"If #antimatter fell upwards, opposite to #gravity, he said, 'one of the cornerstones of [#AlbertEinstein’s theory of] #GeneralRelativity would be wrong, the equivalence principle [which says] if you drop any object on earth, it should fall at the same rate.' "

Gravity test: Antimatter falls down, but where did it all go? | Science and Technology | Al Jazeera
https://www.aljazeera.com/features/2023/9/28/gravity-test-antimatter-falls-down-but-where-did-it-all-go

I am toiling over Dirac. This balancing on the dizzying path between genius and madness is awful. I don't understand the details of Dirac at all.
#Einstein

Where's #PaulDirac?
favourite movie: 2001 A Space Odyssey
favourite singer: Cher
#physics
#quantummechanics
#generalrelativity