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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

#151

Post by blueprint »

tsimionescu wrote: post #48
mkoubaa wrote: post #5

Earlier quoted context omitted.

My understanding is that a particles, like photons, don't have wave shifts. That's an emergent property of many particles

In quantum mechanics, a single particle is also a wave and vice versa. Light is in fact the thing where this observation was first discovered - it had been proven to be a wave for at least a few decades when Einstein discovered the quantum nature of the photovoltaic effect, proving it is also a particle. This discovery was the very start of quantum mechanics, in fact.

"in fact", that was not the very start of quantum mechanics. Einstein's work was preceded by 5-10 years by investigation into the cause of quantized black body radiation. that's why we have Planck's constant and the notion of quantized oscillators. why are you going around talking with such authority? QM and nature is more amazing than you realize. particles are not waves "and vice versa". particles don't exist nor do any classical waves of energy in the way you keep saying as if they're facts. only the wavefunction travels. please be more careful about posting so authoritatively. comments such as yours are why it takes people so long to stumble onto the reality of nature, if they ever are so lucky.

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

#152

Post by blueprint »

d1sxeyes wrote: post #150
blueprint wrote: post #147

Earlier quoted context omitted.

so it's the tone of my textual words? i think you're mistaking my laughter at their blatant and willful ignorance for hostility, and quite honestly it sounds like you're projecting that hostility. from the start I've been incorrectly downvoted and critiqued while being the primary commenter in this child thread providing a semblance of correct view. to be quite frank i deserve an apology, not some nitpick that comes…

At this point anyone who is as certain about the nature of light as you seem to be may well be right, but is demonstrating a level of confidence the literature does not yet seem to support. Although there are those who believe that photons only exist at source and at the detector, there is some experimental evidence which contradicts that (for example, this 2013 paper in which researchers 'read' information from a ph…

so, you're trying to tell me that such reasoning about "dog shit" applies to the ignorance of humanity in general? The reality is the very few people actually understood what they were talking about and a lot of people went around operating on what they didn't really know. So while you call me an asshole for correcting a number of incorrect people in this thread who are themselves rather overconfident, I have to again insist that because I am correcting them or destroying their delusions does not make me hostile and there's a very good chance that you're projecting that impression. The definition of hostility includes the intent to do harm or to be unfriendly, which is in fact what the people I am replying to are doing by spreading misinformation, as if they know. If that's too difficult for you to accept, then best that you do not reply to me, because it would be a waste in both of our time. "falsehood travels a great distance in one night before the truth even crosses the threshold of the door". And the masses sentences Socrates to death just because he called them hypocrites. It's a good thing I know these truths or I would have been damaged by you. It still makes me sad though.

and for what it's worth I don't believe the paper you linked says what you think it says.

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

#153

Post by consilient »

blueprint wrote: post #93
consilient wrote: post #69

Earlier quoted context omitted.

> 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 lite…

photons dont exist, dude, except in connection with and at the site of the detector. study some qft and then you can go talk about it on the internet with authority. and yes direct observation exists. that's what measurement is. and that's all you can ever "observe" unless you incorporate the wavefunction, which also doesn't "exist".

> study some qft

I have. Srednicki and Weinberg are sitting on my bookshelf right now.

> photons dont exist, dude, except in connection with and at the site of the detector.

Exactly backwards.

Photons fall out of mode-expanding asymptotic EM field states just like any other particle. It's the interaction picture that can't be rigorously built up out of particle states.

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

#154

Post by tzs »

sinuhe69 wrote: post #98

Maybe I’m a bit naive here, but I thought finding of many supermassive back holes in the very early universe should be expected, and not a surprise. My chain of thoughts is following: - Blackholes are collapsed masses. In our phase of the universe, they are normally the results of supernovae but only because today stars are the only source of dense masses. - Because the total mass of the universe is constant and the…

> Because the total mass of the universe is constant

It isn't [1]:

> The point is pretty simple: back when you thought energy was conserved, there was a reason why you thought that, namely time-translation invariance. A fancy way of saying “the background on which particles and forces evolve, as well as the dynamical rules governing their motions, are fixed, not changing with time.” But in general relativity that’s simply no longer true. Einstein tells us that space and time are dynamical, and in particular that they can evolve with time. When the space through which particles move is changing, the total energy of those particles is not conserved.

> It’s not that all hell has broken loose; it’s just that we’re considering a more general context than was necessary under Newtonian rules. There is still a single important equation, which is indeed often called “energy-momentum conservation.” It looks like this:

     μν
  ∇ T  = 0
   μ
> The details aren’t important, but the meaning of this equation is straightforward enough: energy and momentum evolve in a precisely specified way in response to the behavior of spacetime around them. If that spacetime is standing completely still, the total energy is constant; if it’s evolving, the energy changes in a completely unambiguous way.

> In the case of dark energy, that evolution is pretty simple: the density of vacuum energy in empty space is absolute constant, even as the volume of a region of space (comoving along with galaxies and other particles) grows as the universe expands. So the total energy, density times volume, goes up.

[1] https://www.preposterousuniverse.com/blog/2010/02/22/energy-...

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

#155

Post by brabel »

antonvs wrote: post #127
brabel wrote: post #113

Earlier quoted context omitted.

But at the same time, I think it's been shown the the size of a galaxy almost always reflects the size of its central black hole... that is, the influence of the central black hole seems to be way, way bigger than what you would expect from the black hole's gravity alone.

That doesn't follow. A galaxy is not like a star system that orbits a single massive object in a single plane. Objects orbit the center of mass of the galaxy, which is made of of an enormous mass of stars and clouds of dust and gas. For example, the central molecular zone (CMZ) is an asymmetrical roughly spherical region, about 1600-1900 light years in diameter, that contains about 60 million solar masses of gas and…

> If anything, causation is likely to work the other way around, in that larger galaxies have larger central black holes because they have denser central regions.

That contradicts the recent observations which show supermassive black holes were present as early as 700 million years after the Big Bang. That's just impossibly little time for supermassive black holes to have formed if they were just the result of matter in the central part of a galaxy to have "fallen" into the presumably smaller black hole you had in the beginning (presumably, because if you assume the black hole was already big to start with, then you must accept that the amount of matter in the center of the galaxy is a consequence of that black hole being there, not the other way around), which I believe is the theory you're proposing as more likely.

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

#156

Post by blueprint »

consilient wrote: post #153
blueprint wrote: post #93

Earlier quoted context omitted.

photons dont exist, dude, except in connection with and at the site of the detector. study some qft and then you can go talk about it on the internet with authority. and yes direct observation exists. that's what measurement is. and that's all you can ever "observe" unless you incorporate the wavefunction, which also doesn't "exist".

> study some qft I have. Srednicki and Weinberg are sitting on my bookshelf right now. > photons dont exist, dude, except in connection with and at the site of the detector. Exactly backwards. Photons fall out of mode-expanding asymptotic EM field states just like any other particle. It's the interaction picture that can't be rigorously built up out of particle states.

good to know you're informed, but it doesn't mean we're communicating effectively.

what i said is not backwards unless you use the inverse understanding of "exist". and how can photons exist without interaction? they don't. they're localizations by detectors. until then, they only "exist" as the probability wave. that's due to nothing localizing them. that's how i mean "exist". so it's not really meaningful to use that word.

btw "any other particle" doesn't fall out of EM fields.

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

#157

Post by claytongulick »

Keysh wrote: post #130
claytongulick wrote: post #109

Earlier quoted context omitted.

See, this is my beef with the reporting on this stuff and the source of my question. The "photo" you're referring to was constructed by a super computer massaging enormous amounts of data to fit a model and constructing an image from weighted averages of thousands of data images across the spectrum from an enormously complex array of detectors in an unfathomably noisy environment [1]. It was presented by the media as…

LISA is a scaled-up version of LIGO, and won't produce "photos" any more than LIGO does. Of course, LIGO has provided extremely good evidence that black holes exist (most of what it detects are the gravitational waves from two black holes merging), but if you don't buy that, then you won't buy LISA's observations, either.

> but if you don't buy that, then you won't buy LISA's observations, either.

Because science is about "buying" it?

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

#158

Post by codethief »

whiw wrote: post #2

> Galactic spectra, which JWST started to send back in earnest at the end of last year, are useful for two reasons. > First, they let astronomers nail down the galaxy’s age. The infrared light JWST collects is reddened, or redshifted, meaning that as it traverses the cosmos, its wavelengths are stretched by the expansion of space. The extent of that redshift lets astronomers determine a galaxy’s distance, and therefo…

> Won't a photon climbing out of a huge gravity well have a huge redshift

Yes. Though see the sibling comments on why the (remaining) gravity well the emitted photon has to climb out of is not particularly huge here.

> thus confounding estimates of distance from us and estimated age?

Generally speaking: No, because people are not stupid. :) See the integrated Sachs-Wolfe effect for a very similar situation (CMB photons traveling through gravitational wells) -> https://en.m.wikipedia.org/wiki/Sachs%E2%80%93Wolfe_effect

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

#159

Post by hxegon »

searealist wrote: post #95
hxegon wrote: post #79

A part of CCC[1] is giant black holes outlasting the end of the universe to be around for the beginning of the next one. Is this a potential explanation? [1] https://en.wikipedia.org/wiki/Conformal_cyclic_cosmology

In CCC, black holes all evaporate before that.

Do they? One of the papers in support of CCC found patterns in the CMB that might have been black holes remaining from the last cycle. I wonder if they'd start eating the new matter created by the big bang and survive.

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

#160

Post by andai »

atoav wrote: post #33
andai wrote: post #16

Earlier quoted context omitted.

You can ask GPT to rewrite it according to your preference. (Not being facetious: I often ask it for bullet points or "explain like I'm 13.")

"Explain me something , I don't care if it is true, because I wouldn't be able to tell anyways"

Guilty as charged! But to be fair, this applies to human writing too:

“Briefly stated, the Gell-Mann Amnesia effect is as follows. You open the newspaper to an article on some subject you know well. In Murray’s case, physics. In mine, show business. You read the article and see the journalist has absolutely no understanding of either the facts or the issues. Often, the article is so wrong it actually presents the story backward—reversing cause and effect. I call these the “wet streets cause rain” stories. Paper’s full of them.

In any case, you read with exasperation or amusement the multiple errors in a story, and then turn the page to national or international affairs, and read as if the rest of the newspaper was somehow more accurate about Palestine than the baloney you just read. You turn the page, and forget what you know.”

– Michael Crichton

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