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Researchers spot black hole feeding at 40x its theoretical limit

arstechnica.com

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Re: Researchers spot black hole feeding at 40x its theoretical limit

#41

Post by KolenCh »

machina_ex_deus wrote: post #27
dustingetz wrote: post #24

Earlier quoted context omitted.

No, this depends on your choice of coordinate system - has been debunked N times on physics reddit in virtually every thread that it comes up. The EH itself is not a singularity in the observers reference frame as they cross it nor do they particularly notice when they do.

I never said EH is a singularity. I said you could notice you're inside as your timelike coordinate becomes the radial coordinate. That's something you could easily notice if you look around, it would correspond to a shrinking universe, and our universe is expanding. The "you won't notice crossing the event horizon" troupe is true only in a very local sense. If you move around and observe the geometry around you, you…

As the black hole getting larger, it is more difficult to notice this difference (of crossing the event horizon or “observe the geometry around you”.) and as we are talking about the whole visible universe being inside a black hole, we are in this extreme large scale.

Also, I’m not sure why you’re arguing about the radial coordinate being time-like. You can only measure in your own local reference frame. You wouldn’t necessarily be able to transform between your own local reference frame to the blackhole’s if you don’t know you’re in one.

The universe as a black hole is actually a very old idea: https://en.wikipedia.org/wiki/Black_hole_cosmology

I’m not saying we are in one, but I’m saying it is not as obviously false as you might be arguing.

Re: Researchers spot black hole feeding at 40x its theoretical limit

#42

Post by goalieca »

deadbabe wrote: post #17
prettyStandard wrote: post #15

Earlier quoted context omitted.

It's not crazy. I'm no physicist, but I understand the math of the Big bang is similar to that of a White hole. What gets a little mind bending for me is the idea that the physics inside the black hole can differ slightly from the ancestor universe. So black holes will preferentially create descendant universes that prefer to create more black holes. This is a different multiverse theory than the quantum many worlds…

Not even close. There’s an infinite amount of numbers in between 0 and 1. But in an infinite multiverse for each of those numbers, you could never see 2.

If I spend long enough, I can count whole numbers to infinity. I cannot possibly count all the numbers between 0 and 1. This so why real numbers have a whole different magnitude of infinity from integers.

Re: Researchers spot black hole feeding at 40x its theoretical limit

#43

Post by gus_massa »

scotty79 wrote: post #31
cowsup wrote: post #26

Earlier quoted context omitted.

I find such thoughts exciting. In the future, children will be taught basic facts that, to us in the first half of the 21st century, are some of the most complicated questions of the universe.

I think knowledge about universe will be mostly the same but streamlined. In our modern day science we have a lot of concepts that exist only because of the path we took to get to where we are now. Most of these interpretations will be cut out once a better ways to proper undestanding is found. I imagine electrons shells, wave function collapse, pseudo-vectors, relativistic mass, xyz ... will go away quickly to be re…

> electrons shells

Not going away. It's based too directly in quantum mechanics principles, and the same tools are used in too may other problems with good results. If you talk to a hard core physicist, they may explain some minor corrections, but the simple model is 99% accurate and the corrections quite technical. Perhaps there is a better theory in the future, but it will be very weird, you really don't want to know it.

> wave function collapse

It's going away, but it may take 500 years. Nobody likes wave function colapse. There is people working to eliminate it, but we have no clue if it's hard, very hard or impossible. I think that a combination of the so-called-many-worlds-interpretation and something-something-decoherence will solve it in 50 years, or 100 years or 500 years. I'm optimistic, but it may take a while......

> pseudo-vectors

Solved? The problem is drawing normal vectors that are 1-forms and pseudo-vectors that are mostly 2-forms in the same space. Most pseudo-vectors are like a tiny surface area instead of a tiny arrow. But people love to draw all of them as arrows and that causes the problem. Also, in special relativity the electric field (vector) and magnetic field (pseudo-vector) are combined in a single weird entity that fixes the problem. There is still the problem with the weak force, but I think it's solved once you replace mass with the Higgs boson. So it's "solved" if you like to use a little more math and want to translate it to everyone else that likes arrows.

> relativistic mass

Solved. Most modern Special Relativity books try to avoid relativistic mass. The problem is that you need number to accelerate to one side and a different number to accelerate to the front/rear. So it's better to skip it and use other equations. The usual "relativistic mass" is good for accelerations to one side to get circular movements, so it's nice for some problems.

> xyz

I have no idea what it means.

Re: Researchers spot black hole feeding at 40x its theoretical limit

#44

Post by MrMcCall »

gus_massa wrote: post #23
MrMcCall wrote: post #16

Earlier quoted context omitted.

Dark energy is the force that counteracts the combined gravity of our enormous universe. It also keeps the electrons flowing around the nucleus, but not into it. The universe started with a single Big Bang, but is maintained by an interrelated force continually applied that keeps allowing it to resist collapse, the resulting system allowing local minima such as Earth's sweet spot of smallish sun + gentle orbit. It's…

> [Dark energy] also keeps the electrons flowing around the nucleus, but not into it. That's totaly wrong. The movenent of electrons arround rhe nucleus is explained by the Schoedinger equation that does not use dark energy at all.

Movement, yes, but does it explain why they just keep moving about in that cloud?

I don't think so, but I'm open to learning.

Re: Researchers spot black hole feeding at 40x its theoretical limit

#45

Post by MrMcCall »

jdhwosnhw wrote: post #30
MrMcCall wrote: post #16

Earlier quoted context omitted.

Dark energy is the force that counteracts the combined gravity of our enormous universe. It also keeps the electrons flowing around the nucleus, but not into it. The universe started with a single Big Bang, but is maintained by an interrelated force continually applied that keeps allowing it to resist collapse, the resulting system allowing local minima such as Earth's sweet spot of smallish sun + gentle orbit. It's…

> It also keeps the electrons flowing around the nucleus, but not into it. Asa cautionary note to other readers, this statement is not consistent with any theory of which I am aware, and it’s certainly not a concept accepted by mainstream physics

Eugene Parker and Ludwig Boltzmann are familiar with your argument, and I doubt you even have Lord Kelvin's credentials.

As Prof. Parker said, "We'll see who falls flat." (That's a paraphrase from memory; I doubt it's an exact quote.)

Re: Researchers spot black hole feeding at 40x its theoretical limit

#46

Post by MrMcCall »

ceejayoz wrote: post #18
MrMcCall wrote: post #16

Earlier quoted context omitted.

Dark energy is the force that counteracts the combined gravity of our enormous universe. It also keeps the electrons flowing around the nucleus, but not into it. The universe started with a single Big Bang, but is maintained by an interrelated force continually applied that keeps allowing it to resist collapse, the resulting system allowing local minima such as Earth's sweet spot of smallish sun + gentle orbit. It's…

> It's almost like it was designed to be perfect… It’s almost like the ones that aren’t ideal for life don’t tend to have much life to notice that fact.

Well, yeah, that's how it works. On Earth here, we're an oasis of warm thermodynamic blessedness in a sea of frigid brutality.

Be thankful there's no humans on Uranus.

Re: Researchers spot black hole feeding at 40x its theoretical limit

#47

Post by gus_massa »

MrMcCall wrote: post #44
gus_massa wrote: post #23

Earlier quoted context omitted.

> [Dark energy] also keeps the electrons flowing around the nucleus, but not into it. That's totaly wrong. The movenent of electrons arround rhe nucleus is explained by the Schoedinger equation that does not use dark energy at all.

Movement, yes, but does it explain why they just keep moving about in that cloud? I don't think so, but I'm open to learning.

The Schoedinger equation is a partial diferential equation. When you solve it, you get the eigenvalues and eigenvectors.

The eigenvalues are the energies. The differences if energies are easy to measure experimentaly looking at the light of discharge lamps. Most of the science of early 20th century is triying to find a theory that explains the colors in that light.

The eigenvectors of the Schoedinger equations are the clouds distributions of the electrons. I'm not sure how difficult is to measure them directly, but they are important to get the size and shape of molecules and the positions of atoms inside crystals and a lot of other stuff.

The same theory that explains the the light of discharge lamps and the electronic clouds also explains the leds in the screen and the transistors in the procesor of yoyr phone.

And dark energy is not used in any of these calcuñations.

Re: Researchers spot black hole feeding at 40x its theoretical limit

#48

Post by scotty79 »

gus_massa wrote: post #43
scotty79 wrote: post #31

Earlier quoted context omitted.

I think knowledge about universe will be mostly the same but streamlined. In our modern day science we have a lot of concepts that exist only because of the path we took to get to where we are now. Most of these interpretations will be cut out once a better ways to proper undestanding is found. I imagine electrons shells, wave function collapse, pseudo-vectors, relativistic mass, xyz ... will go away quickly to be re…

> electrons shells Not going away. It's based too directly in quantum mechanics principles, and the same tools are used in too may other problems with good results. If you talk to a hard core physicist, they may explain some minor corrections, but the simple model is 99% accurate and the corrections quite technical. Perhaps there is a better theory in the future, but it will be very weird, you really don't want to kn…

> electrons shells

Has almost nothing to do with actual orbitals. "Filling electron shells", "octets" are just idiotic old rule of thumb ideas only accidentally aligning with reality.

> wave function collapse

I think it's going away pretty fast as we exprimentally find quantum behaviors in increasingly macroscopic objects. At some point it will become clear that nothing collapses into particles and it's just that through interaction wavefunctions narrow down when they exchange some energy and momentum. But other interactions can spread them apart back again. We are gonna create consistent description of the process in both directions.

> pseudo-vectors

they are still used but they are gonna be replaced by bivectors as they are more natural

> relativistic mass

true that it's partially sovled, but we need a generation or two of people not mentioning at all in educational context or metioning it negatively for it finally go away ... today it's still treated as "useful educational metaphor" which it is not

> xyz

Basically breaking down math calculations to coordinate wise caluclations

People will stop doing that because most symbolic maths in education is going to be done with computers and rarely anyone will be doing any element-wise transforamtions on anything.

Re: Researchers spot black hole feeding at 40x its theoretical limit

#49

Post by lostmsu »

machina_ex_deus wrote: post #22
aurareturn wrote: post #8

On the topic of black holes, there is a recent paper on black holes potentially converting mass into dark energy: https://iopscience.iop.org/article/10.1088/1475-7516/2024/10... I'm not a physicist but it's interesting to think about the implications: 1. No singularity at the center of a black hole 2. Universe's expansion rate is not constant because it's blackholes powering it with matter 3. Eventually expansion slo…

The universe is not inside a black hole. Inside black holes the radial coordinate is time like, which is definitely not true in our universe, where the time coordinate is timelike, and the radial coordinate is space like. Inside of black holes looks nothing like ordinary spacetime. Inside black hole, everything in your future is with decreasing radial coordinate, which means space is shrinking until you hit the singu…

I think for this to be a complete explanation, it needs to be shown that what was "the time" coordinate is not expanding in some sense.

Does volume even make sense in GR?

Thought experiment here would be: suppose me and you appeared stationery (from the point of view of the outside reference frame) just above the horizon of a non-rotating black hole in the manner of Boltzmann brains. We immediately start falling and cross the horizon. Now will you see me receding from you or going at you? Will I be red-shifted or blue-shifted?

Re: Researchers spot black hole feeding at 40x its theoretical limit

#50

Post by ceejayoz »

MrMcCall wrote: post #46
ceejayoz wrote: post #18

Earlier quoted context omitted.

> It's almost like it was designed to be perfect… It’s almost like the ones that aren’t ideal for life don’t tend to have much life to notice that fact.

Well, yeah, that's how it works. On Earth here, we're an oasis of warm thermodynamic blessedness in a sea of frigid brutality. Be thankful there's no humans on Uranus.

Any life in the universe that evolved on Uranus-style systems will similarly be grateful not to be here on Earth. Their religions might go on about the perfect conditions compared to those scorchingly hot ones closer to the Sun.

Hell, penguins don’t even like the tropics on the same planet.

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