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JWST spots giant black holes all over the early universe

quantamagazine.org

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Re: JWST spots giant black holes all over the early universe

#61

Post by dotnet00 »

somat wrote: post #21

So this is one of them "shower thoughts", you know, those stupid things you think about while working on something else.That is, purely science fiction. Can an analog be drawn between galaxies and solar system creation theories, with several orders of magnitudes in time required for formation due to scale difference. That is, the galaxies we see with their billions of stars are actually young proto accretion disks. w…

It is worth considering that a black hole's hold on its galaxy is not as strong as a sun-like star's on its accretion disk. Our Sun is 99% of the mass of the solar system, our Sagittarius A* is ~4 million solar masses, while our Milky Way is 800 billion solar masses.

On top of that, black hole growth rate slows to nearly a stop at ~270 billion solar masses, so even if a black hole manages to meet the rare conditions to get that heavy, it would still be dwarfed by its galaxy.

Re: JWST spots giant black holes all over the early universe

#62

Post by dotnet00 »

mabbo wrote: post #59
jsbisviewtiful wrote: post #32

It's pretty cool how much JWST has caught in such a short amount of time. Give it another 5-10 years and we may have some absolutely groundbreaking new celestial theories.

It's really worthwhile to compare it to the hubble in that regard. Pre-hubble, the question was whether the universe would contract into a big crunch, expand slower and slower forever, or balance out somehow in the middle. Then hubble got a good look at universal expansion and we noticed it was speeding up and now we've got Lambda-CDM from that. From this we know what the long term fate of the universe is. That there…

Heat death is one of the possibilities, but it's still very much an open question, as it depends on the curvature of the universe and the nature of dark energy.

Re: JWST spots giant black holes all over the early universe

#63

Post by _0w8t »

tsimionescu wrote: post #51
blueprint wrote: post #15

Earlier quoted context omitted.

Your comment is a bit strange. Light doesn't travel as photons. Photons exclusively exist at the site and instant of detection of the wave of probability of detection that light really travels as. When light is redshifted, it loses energy, therefore the wavelength becomes longer.

That is not the current understanding of quantum mechanics, as far as I know. Wave/particle dualism says that different experiments can either view light as a wave or a particle (never both) and that speaking about the nature of light when an experiment is not being performed is non-scientific by definition. Importantly, light very much behaves like a conventional wave in many real experiments - the interferometer ex…

Experimentally one never observes waves. Light is detected based on its interaction with electrons and that is always by an electron absorbing a quanta of energy, not via some continuous process as would be the case with waves.

Classically one can imagine that as if electron was hit by a particle. But then we have light diffraction and interference, which classically is described as a wave. So from a classical point of view light travels as a wave but interact as a particle.

As of nature of the light, then consider that there is a reformulation of a classical electrodynamics that eliminates electromagnetic waves all together. There are only electrons that interacts with each other directly with no waves in between. Feynman spent quite some time trying to develop quantum electrodynamic based on that. He failed. Still the point stands that we never observe light directly but only through its effects on electrons and other charged particles. So it could be that what we call light is a theoretical artifact and there is no light in reality.

Re: JWST spots giant black holes all over the early universe

#64

Post by Smoosh »

quakeguy wrote: post #54
antognini wrote: post #50

Earlier quoted context omitted.

The photons that are getting observed are emitted from the accretion disk, which is not very close to the event horizon. You can estimate how close to the event horizon the disk is based on how broad the spectral lines are. The part of the disk that is coming towards you will be blueshifted and the part of the disk that is rotating away will be redshifted. From that (which is independent of the overall depth of the p…

Well, this is awesome.

Sometimes I despair for humanity [see advertising/social media/politics], but then I see something like this and think, we're doing pretty well for self-taught primates.

Re: JWST spots giant black holes all over the early universe

#65

Post by funnymony »

claytongulick wrote: post #38

Can someone who really knows this stuff clarify my understanding? I've been given to understand that black holes remain a physics theory that has not been directly observed or proven. I thought that we had a fair amount of observational evidence that suggests their existence, but no "smoking gun" proof of it, and that these types of "observed a black hole" articles are a little misleading - that in reality, what was…

I’ve read something like: there are bunch of observations of extremely dense masses in various suroundings. Talented people can find explanations other than black holes in each case. But that feels adhoc, and black hole fits quite nicely for whole class of observations. Current consensus is that b holes exist.

Re: JWST spots giant black holes all over the early universe

#66

Post by dylan604 »

Smoosh wrote: post #64
quakeguy wrote: post #54

Earlier quoted context omitted.

Well, this is awesome.

Sometimes I despair for humanity [see advertising/social media/politics], but then I see something like this and think, we're doing pretty well for self-taught primates.

and then we see all of the belief systems to mock, punish, or worse people that are trying to expand human knowledge. looking back at history, you have to wonder where we might be now if there wasn't this attempts at mass eradication of learning. there are times i wonder if we're heading in that direction again. this time, rather than burning the Library of Alexandria or locking everything in catacombs, if we're not just trying to get there on a low-n-slow approach.

Re: JWST spots giant black holes all over the early universe

#67

Post by dylan604 »

marcosdumay wrote: post #13
ben_w wrote: post #4

Earlier quoted context omitted.

> Won't a photon climbing out of a huge gravity well have a huge redshift, Yes > thus confounding estimates of distance from us and estimated age? Not if you know, or can get a good estimate of, the potential well it's climbing out of. That said, Brian Cox does sometimes joke that astronomers round π to 1; while I wouldn't know about the reality, it's probably safe to infer at least some frustration on his part about…

The joke was way more true at the 20th century. There were many really important measurements where we got unprecedentedly precision, enough to say it's X, 100X, or something in between. Nowadays astronomy got a lot more precise. But there are disagreements on how much confidence to put on that extra precision.

sometimes, i wonder if astronomy/physics were to only use unsigned numbers, if things would just make more sense. you'd get much more precision, and then you wouldn't have to worry about "but the math says it's possible" issues by taking everything by * -1.

Re: JWST spots giant black holes all over the early universe

#68

Post by labster »

dylan604 wrote: post #67
marcosdumay wrote: post #13

Earlier quoted context omitted.

The joke was way more true at the 20th century. There were many really important measurements where we got unprecedentedly precision, enough to say it's X, 100X, or something in between. Nowadays astronomy got a lot more precise. But there are disagreements on how much confidence to put on that extra precision.

sometimes, i wonder if astronomy/physics were to only use unsigned numbers, if things would just make more sense. you'd get much more precision, and then you wouldn't have to worry about "but the math says it's possible" issues by taking everything by * -1.

Jesse, what are you talking about?

Re: JWST spots giant black holes all over the early universe

#69

Post by consilient »

_0w8t wrote: post #63
tsimionescu wrote: post #51

Earlier quoted context omitted.

That is not the current understanding of quantum mechanics, as far as I know. Wave/particle dualism says that different experiments can either view light as a wave or a particle (never both) and that speaking about the nature of light when an experiment is not being performed is non-scientific by definition. Importantly, light very much behaves like a conventional wave in many real experiments - the interferometer ex…

Experimentally one never observes waves. Light is detected based on its interaction with electrons and that is always by an electron absorbing a quanta of energy, not via some continuous process as would be the case with waves. Classically one can imagine that as if electron was hit by a particle. But then we have light diffraction and interference, which classically is described as a wave. So from a classical point…

> So from a classical point of view light travels as a wave but interact as a particle.

And the classical point of view is wrong. Photons resemble classical particles in a few respects, and classical waves in a few others, but at the end of the day they're neither.

> Still the point stands that we never observe light directly but only through its effects on electrons and other charged particles.

This is true of literally everything. "Direct" observation does not exist. Every atom, every cell, every person, every planet, every star - you know them by their effect on your sense-data, or else not at all.

Re: JWST spots giant black holes all over the early universe

#70

Post by dylan604 »

labster wrote: post #68
dylan604 wrote: post #67

Earlier quoted context omitted.

sometimes, i wonder if astronomy/physics were to only use unsigned numbers, if things would just make more sense. you'd get much more precision, and then you wouldn't have to worry about "but the math says it's possible" issues by taking everything by * -1.

Jesse, what are you talking about?

Well, Mr White, if you look at all of the "weirdness" in physics with theories coming out because "the math says it's possible", then you'd see that it would be much more simple if we were not allowed to have negative numbers because we're only using u64 integers. we'd have more digits for precision as well.
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