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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

#51

Post by tsimionescu »

blueprint wrote: post #15
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

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 experiment being one of the oldest and most well known. It is not a probability wave in that case, but an actual physical wave (now known to be an oscillation in the electro magnetic field, but long assumed to be a mechanical wave in the luminiferous aether).

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

#52

Post by antognini »

xigency wrote: post #40
ajross wrote: post #20

Earlier quoted context omitted.

> Won't a photon climbing out of a huge gravity well have a huge redshift, thus confounding estimates of distance from us and estimated age? Of course it will. It will also have a redshift related to the expansion of the space it's been travelling through. Both of those corrections are absolutely part of the model. It's not nearly as simple as "Astronomers forgot about General Relativity!". But I guess it's true (to…

> Both of those corrections are absolutely part of the model Is there a way to gain a better understanding of how these parameters are modeled and what the scientific evidence is for the various phenomena in astrophysics? It's somewhat perplexing to me as an outsider of the field to understand how things like mass and distance of stars and planetary bodies are determined when 1) the scales are so outside of conventio…

I know Terence Tao (yes, that Terence Tao) is working on a book about the cosmic distance ladder, but sadly it's not out yet. (I guess he probably has other projects he's working on.) But he does have some slides from talks he's given: https://terrytao.files.wordpress.com/2020/10/cosmic-distance...

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

#53

Post by vient »

mekkkkkk wrote: post #46
vient wrote: post #31

Earlier quoted context omitted.

In ordinary strategies you already have an assumption of immediate information transfer from unit to player - you see what each unit is seeing. This can be kept so you will see you units moving in real time but as things get further from your units on the map, the older info about them you get.

That's interesting. Wouldn't it lead to paradoxes where enemy units are shown at multiple places at once, observed from different frames of reference? Would be incredibly confusing, but confusing games can be fun too. EDIT: Also if a unit traveled close to C away from a friendly unit, and then back, whos reference is real?

Observations merging is interesting question. Simplest thing to do may be to show enemy unit as it is seen by our unit closest to them (here we just use "real" distance in internal game's coordinates). In other words, Voronoi diagram is built with our units as seeds, and enemies are shown as seen from their cell center. This would evade enemy "phantoms" but enemies can suddenly "teleport" as they move closer to other friendly unit (or can't they? I don't really know).

In lore it may be explained like "our units know distances to objects and choose closest one among all units" since we already use "units can communicate instantly" magic.

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

#54

Post by quakeguy »

antognini wrote: post #50
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…

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.

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

#55

Post by Larrikin »

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…

There's been more than one picture of one

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

#56

Post by krukah »

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…

The theoretical prediction of black holes dates back to 1916, when Karl Schwarzschild proposed a solution to Einstein's field equations that were part of his general theory of relativity. General relativity is arguably the most robust theory in physics - that being said, general relativity introduces some tension with the other most robust theory in physics, namely quantum mechanics and the Standard Model. These two theories are largely accepted to be accurate and correct, and since they predict different phenomena at different length scales, most scientists have no trouble subscribing to both.

With respect to "direct observation" of a black hole, astronomers at the Event Horizon Telescope successfully reconstructed pictures of a black hole using light in the visible spectrum. But to be fair, this comes after decades of overwhelming experimental evidence of black holes + GR. The EHT result probably received the media attention it did because it is easily interpretable as nice lil JPEG, rather than a 12-page paper with dense plots and LaTeX.

See https://en.wikipedia.org/wiki/Tests_of_general_relativity

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

#57

Post by Zamicol »

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…

Einstein didn't think black holes existed (1916) and it took until 1971 with Cygnus X-1 for serious consideration, which was the smoking gun. 55 years of being considered probably a math fluke and then observational evidence.

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

#58

Post by throwuwu »

vagab0nd wrote: post #29
javajosh wrote: post #3

This is super cool. I think it's funny how Quanta writes, "It is expected because JWST was built, in part, to find the ancient objects." "Ancient" is equivalent to "distant" because of special relativity. It's an odd thing, astronomy - it's a real world time-traveling observation, except we're limited in resolution and we can't look here only there . If it was a game mechanic I'd call it a cunning way to impose inter…

> If it was a game mechanic I'd call it a cunning way to impose internally consistent limits on what the player can know. But if you assume it's a multi-player game, wouldn't it be easier to implement a global space-time? The reality is that you have to keep an internal clock for each player.

Partition them by velocity

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

#59

Post by mabbo »

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 are galaxies we can see that but we can never reach. That the universe will end from the slow burn out of heat death and not return to the singularity.

Just imagine what we'll know after 5-10 years of JWST.

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