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JWST spots giant black holes all over the early universe

quantamagazine.org

41–50 of 186 posts

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

#41
post #14

I wish stories like this were a more straight forward counting of the interesting facts and relevant input from experts. I don't really need the origin story of the conference this finding was discussed at.

It actually made the story more interesting to me. I like learning the human side to the stories.

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

#43

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…

Scientist recently got a good picture of one

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

#44
post #14

I wish stories like this were a more straight forward counting of the interesting facts and relevant input from experts. I don't really need the origin story of the conference this finding was discussed at.

The first spate of articles from this publication were like this, which really made it stand apart from the others. Somehow a complete inversion has taken place since then.

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

#45

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…

As far as I know, the existence of black holes is accepted by basically every astrophysicist.

There are several smoking guns:

https://en.wikipedia.org/wiki/Black_hole#Observational_evide...

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

#46
post #31

Earlier quoted context omitted.

Wouldn't that be incredibly hard, considering that the players perspective is disconnected from the units? I observe my base and order a group of units to go to some place on the minimap. I see them moving along on their way, and decide to scroll to them. Only to realize that they already arrived and got massacred by the enemy. I go back to my base only to realize that it was destroyed ages ago (in its frame of refer…

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?

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

#47
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…

[flagged]

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

#48
post #5
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…

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.

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

#49
post #8

Earlier quoted context omitted.

> internally consistent limits on what the player can know Interesting thought. Can you expand? What do you mean by this?

Not the original author but my first interpretation is that this means, if it were in a video game, it would be a way to self-reinforce "fog of war" where you can only have extremely local information and you don't want extra information to leak to the players.

Wouldn't it be slightly easier to just, you know, visually obscure the opponent's base?

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

#50
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 potential well) you can figure out how fast the disk is rotating. And from that you can figure out how far away the disk is from the black hole.

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