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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

#161

Post by dotancohen »

rmu09 wrote: post #138
dotancohen wrote: post #116

Earlier quoted context omitted.

Then you're so close to 10 that you can just use 10. I actually did that on a physics exam once. Somehow I had a value with pi squared. I just replaced it with 10. I don't remember if I got that question right or wrong - I'm hard pressed to think of a situation where pi squared actually legitimately shows up.

Surface area of a Torus?

Not that I remember, or really relevant to undergrad physics - I'm pretty sure it was physics. Fusion and accretion disks are above my pay grade!

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

#162

Post by kridsdale3 »

marmakoide wrote: post #104
dylan604 wrote: post #66

Earlier quoted context omitted.

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…

The STEM people will just need flashy robes, long grey hairs and market themselves as the magicians that can read the runes, command to the machine spirits of yore, and make the food grow. It's good fun to pester the nerds until the wifi is down.

Fantasy lit is full of stories about the good people rebelling against the evil wizards and their machinations.

Luke fighting Emperor Palpatine? What does Luke or any of the Rebels know about managing an org of Peta-scale population? Or what myriad threats to the galaxy the Emperor was handling with his century of experience, network of millions of loyal agents, and vast magical ability? I'm sure that will all be fine.

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

#163

Post by perrygeo »

claytongulick wrote: post #109
thehappypm wrote: post #43

Earlier quoted context omitted.

Scientist recently got a good picture of one

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…

> It was presented by the media as a "photo", but it seems to me like it's more similar to the "image" we get from reconstruction of wifi signals

Are you suggesting that emitting or reflecting visible radiation is required before we can prove something exists in objective reality? Your own point about Wifi signals proves you wrong - we can detect wifi in other wavelengths and thus learn a great deal about it. Just like we can with black holes.

There is no distinction between "images" and "photos" - they're both electromagnetic radiation converted to a visual medium. There's nothing unique about radiation in the 380 to 700 nanometers wavelength range that makes it somehow more scientifically valid for remote sensing.

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

#164

Post by consilient »

blueprint wrote: post #156
consilient wrote: post #153

Earlier quoted context omitted.

> 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 th…

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

I very obviously meant that XYZ-particle states fall out of mode expansions of the XYZ-field, not that all particles are EM quanta.

> what i said is not backwards unless you use the inverse understanding of "exist". and how can photons exist without interaction?

Exactly the same way any other field configuration can? The state space of the free EM field simply is the photon Fock space.

The state space of an interacting 4D EM field is unknown and may well not exist, hence the need for perturbative approaches and renormalization - in which particle states again emerge as terms in the perturbation series.

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

#165

Post by olddustytrail »

dylan604 wrote: post #10
hutzlibu wrote: post #9

Earlier quoted context omitted.

I also don't know how accurate that description is, but this comic comes to mind: https://xkcd.com/2205/ But I mean, space is really, really big and we are observing from one single spot with (on cosmological scale probably) primitive technology. So of course most of it is guessing and when you "guess" a lot of things, it maybe does not matter a lot, if you have 3.41 Pi or 1, when the data you have are rough estimate…

What if you have 3.14Pi?

That's pretty much pi squared. Which, for weirdly good reason, is close to the value of G in meters per second squared.

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

#166

Post by d1sxeyes »

blueprint wrote: post #152
d1sxeyes wrote: post #150

Earlier quoted context omitted.

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 agai…

OK.

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

#167

Post by andrewflnr »

AnimalMuppet wrote: post #144
andrewflnr wrote: post #134

Earlier quoted context omitted.

I believe this actually is one of the hypotheses about black hole interiors, though I forget the name. Nothing to do with terrestrial storms or vortices, though; a black hole doesn't have to have any rotation at all.

There are rotating black holes ( https://en.wikipedia.org/wiki/Rotating_black_hole ).

Yes, obviously most real black holes are rotating. I didn't say otherwise.

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

#168

Post by zardo »

kridsdale3 wrote: post #162
marmakoide wrote: post #104

Earlier quoted context omitted.

The STEM people will just need flashy robes, long grey hairs and market themselves as the magicians that can read the runes, command to the machine spirits of yore, and make the food grow. It's good fun to pester the nerds until the wifi is down.

Fantasy lit is full of stories about the good people rebelling against the evil wizards and their machinations. Luke fighting Emperor Palpatine? What does Luke or any of the Rebels know about managing an org of Peta-scale population? Or what myriad threats to the galaxy the Emperor was handling with his century of experience, network of millions of loyal agents, and vast magical ability? I'm sure that will all be fin…

The emperor wasn't doing such a great job holding the galaxy together as a political unit, there was a successful overthrow of his rule after just a couple decades in power.

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

#169

Post by andrewflnr »

hxegon wrote: post #159
searealist wrote: post #95

Earlier quoted context omitted.

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.

They (think they) found traces of the last black holes evaporating. That has to finish happening before the next CCC cycle.

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

#170

Post by andrewflnr »

claytongulick wrote: post #157
Keysh wrote: post #130

Earlier quoted context omitted.

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?

Yes, in the real world. Even if it wasn't, you've made this conversation about you personally "buying" it, so yeah.
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