Black Holes Shown to Act Like Quantum Particles | Hacker News Reader

Black Holes Shown to Act Like Quantum Particles

quantamagazine.org

36 pointstheafh7 comments

“The expectation is that quantum field theory does describe classical physics,” Roiban said. “It turns out that it is in this way that it does it, by having zero uncertainty in some states.”

> The upshot is that classical waves are easier to describe in the language of quantum mechanics than researchers feared. “A gravitational wave, or a wave of any kind, is something big and floppy. It should depend on many little things,” said Roiban. But “once you know the collision plus one photon or one graviton in the final state, then you know everything.”

Isn't this essentially applying QFT in high gravity environments? Something that's long been sought?

Am I missing something?

It's not actually a quantum theory, just a quantum approach. We use simplifying computational models for both black holes and large (or high energy, or just weird) quantum systems, and these researchers think they found success porting over some of those techniques. We really, really want spacetime to behave like quantum fields do, but in general it just behaves completely differently. In this particular instance though, those differences don't matter enough to make the tools of QFT totally useless. Quantum physicists spend a lot of time integrating lots and lots of tiny effects that may or may not interact with each other in strange ways, which is handy experience for working with colliding black holes. Or rather, solving a subproblem coming from certain simplifying techniques.

Wouldn’t a singularity be the smallest point possible? By definition it is pretty much a cyclone of the smallest units of space time fabric. Any particle would need to exist above this scale in order to exist within the construct of the universe. If there were any object smaller than this it would mean that whatever makes up a unit/point/pixel of space time fabric is actually an emergent construct of much smaller units. If there were smaller said units composing even space time itself, perhaps these would be or be composed by a finally irreducibly small unit, the properties of which give rise to all variations of matter/energy, the laws which govern them and their equality and convertablity according to special relativity.

Most scientists do not think that black holes have a "real singularity." The idea of a mass that occupies a single point in space comes from taking Einstein's equations beyond the event horizon, ie. the curvature of space is greater than light so means nothing can have any resistance to distance/size. At some point between the event horizon and the center, quantum gravity (which is not understood) has to come into the picture. One idea is the "black hole firewall," which is that mass gets "stuck" at the boundary of the black hole.

White hole > Big Bang/Supermassive White Hole https://en.wikipedia.org/wiki/White_hole :

> Some researchers have proposed that when a black hole forms, a Big Bang may occur at the core/singularity, which would create a new universe that expands outside of the parent universe

Where's the exit on this thing?

Do the CMB or GWB indicate that the Shapley Attractor / Great Attractor interaction is the omnidirectional mouth / center of it all, or no? https://en.wikipedia.org/wiki/Shapley_Supercluster

Gravitational wave background > Cosmological sources https://en.wikipedia.org/wiki/Gravitational_wave_background

... FWIU, all we've done is observe minute confirmatory fluctuations from the ground; e.g. LIGO (Nobel Prize in Physics 2017, Thorne, NumFocus-supported tools)? Could that tell us where the center is? Should there even be one if we're actually inside a white hole / black hole combo?

What "dark matter" do we subtract or add to the CMB, GWB,?

... Severe questions of cosmological topology, in regards to a manifold for holographic projection

@PBSSpaceTime videos:

"Where Is The Center of The Universe?" (2022) https://youtu.be/BOLHtIWLkHg

"Could The Universe Be Inside A Black Hole?" (2022) https://youtu.be/jeRgFqbBM5E

"The Holographic Universe Explained" (2019) https://youtu.be/klpDHn8viX8

"Are Black Holes Actually Fuzzballs?" (2022) https://youtu.be/351JCOvKcYw

From https://www.quantamagazine.org/massive-black-holes-shown-to-... :

> Physicists are using quantum math to understand what happens when black holes collide. In a surprise, they’ve shown that a single particle can describe a collision’s entire gravitational wave.

"Scale invariance in quantum field theory" https://en.wikipedia.org/wiki/Scale_invariance#Scale_invaria...

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