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The James Webb Space Telescope is finding too many early galaxies

skyandtelescope.org

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Re: The James Webb Space Telescope is finding too many early galaxies

#81

Post by seszett »

seanw444 wrote: post #38
make3 wrote: post #34

Earlier quoted context omitted.

how can that work if nothing is faster than light in the referential of the objects being compared? is it that space expands faster than light moves?

Correct, as I understand it. No matter can travel at the speed of light, and no light can travel faster than the speed of light. But the rule doesn't extend to the rate of expansion of the "field" on which those things exist.

When I read this, it seems to me like this is more or less the same as saying that the speed of light is decreasing, but I am probably wrong?

Re: The James Webb Space Telescope is finding too many early galaxies

#82

Post by atemerev »

Something is wrong with the cosmic distance ladder. Space is anisotropic, or gravity interacts with itself somehow. The distances are not what they seem to be. I think this will eventually be the solution to the galaxy rotation / dark matter problem.

Re: The James Webb Space Telescope is finding too many early galaxies

#83

Post by afro88 »

eganist wrote: post #15
cwkoss wrote: post #14

Is it possible that the 'edge' of universe reflects light? Have scientists been able to conclusively rule that out somehow? Does the universe even have an edge? What is our current understanding of what the boundaries of the universe might be like?

> Is it possible that the 'edge' of universe reflects light? Have scientists been able to conclusively rule that out somehow? It's not an edge the way you think. It's the edge of what we can see based on the known age of the universe and how much light has reached us. I.e no real boundaries as best as we can tell. The best way you can look at this is that early galaxies are being found earlier than expected based on…

I guess it's reasonable to assume that there are parts of the universe that are far older and much further away (ie, their light hasn't reached us yet). Which would mean we can never really guess the age of the universe. We can only guess the age of our local area?

Which kind of sounds a bit like the whole "everything revoles around earth" transitioning to "everything revolves around the sun". The universe is what light has reached us transitioning to the area of light that has reached us is just a small spec of the actual universe?

Re: The James Webb Space Telescope is finding too many early galaxies

#84

Post by Enginerrrd »

barbazoo wrote: post #78
college_physics wrote: post #59

I don't know if this instance qualifies as one, but I think its fair to say that cosmology is the one domain of "fundamental" physics where "discrepancies" or question marks keep piling up and not really resolving. It the pattern of previous science revolutions repeats, there could come a point where reinterpreting the large existing body of knowledge using a different paradigm would explain an number of "oddities" i…

> It the pattern of previous science revolutions repeats, there could come a point where reinterpreting the large existing body of knowledge using a different paradigm would explain an number of "oddities" in a more economical way. Could we train a GPT3 like model with the entire corpus of astronomical research and try to answer some questions that way?

I'd say not a chance.

GPT3 can regurgitate, and, in my opinion, even use knowledge, but I don't think it can synthesize knowledge.

Re: The James Webb Space Telescope is finding too many early galaxies

#85

Post by largbae »

barbazoo wrote: post #78
college_physics wrote: post #59

I don't know if this instance qualifies as one, but I think its fair to say that cosmology is the one domain of "fundamental" physics where "discrepancies" or question marks keep piling up and not really resolving. It the pattern of previous science revolutions repeats, there could come a point where reinterpreting the large existing body of knowledge using a different paradigm would explain an number of "oddities" i…

> It the pattern of previous science revolutions repeats, there could come a point where reinterpreting the large existing body of knowledge using a different paradigm would explain an number of "oddities" in a more economical way. Could we train a GPT3 like model with the entire corpus of astronomical research and try to answer some questions that way?

Already done. They came back with the answer: "42"

Re: The James Webb Space Telescope is finding too many early galaxies

#86

Post by ivalm »

afro88 wrote: post #83
eganist wrote: post #15

Earlier quoted context omitted.

> Is it possible that the 'edge' of universe reflects light? Have scientists been able to conclusively rule that out somehow? It's not an edge the way you think. It's the edge of what we can see based on the known age of the universe and how much light has reached us. I.e no real boundaries as best as we can tell. The best way you can look at this is that early galaxies are being found earlier than expected based on…

I guess it's reasonable to assume that there are parts of the universe that are far older and much further away (ie, their light hasn't reached us yet). Which would mean we can never really guess the age of the universe. We can only guess the age of our local area? Which kind of sounds a bit like the whole "everything revoles around earth" transitioning to "everything revolves around the sun". The universe is what li…

> I guess it's reasonable to assume that there are parts of the universe that are far older and much further away (ie, their light hasn't reached us yet). Which would mean we can never really guess the age of the universe. We can only guess the age of our local area?

But older parts of the universe would emit light that would have more time to travel. So unless space is not continuous, we can confidently say that no older light exists. The main counterfactual is that there is an older universe that is discontinuous with the observable universe (but in what sense is that older universe part of "ours" then?).

Re: The James Webb Space Telescope is finding too many early galaxies

#87

Post by purpleblue »

barbazoo wrote: post #78
college_physics wrote: post #59

I don't know if this instance qualifies as one, but I think its fair to say that cosmology is the one domain of "fundamental" physics where "discrepancies" or question marks keep piling up and not really resolving. It the pattern of previous science revolutions repeats, there could come a point where reinterpreting the large existing body of knowledge using a different paradigm would explain an number of "oddities" i…

> It the pattern of previous science revolutions repeats, there could come a point where reinterpreting the large existing body of knowledge using a different paradigm would explain an number of "oddities" in a more economical way. Could we train a GPT3 like model with the entire corpus of astronomical research and try to answer some questions that way?

If you give GPT3 code with a bug in it, and ask it to find the bug, it can't really do that. I'm pretty sure giving it all the data and asking it why things aren't working the way it should, it wouldn't have actual knowledge.

There's a depth to explaining things that GPT still can't do. It's still astonishing, and has completely changed my idea on what AI can do, like write plays with very incredible context (better than most humans!) but there are still major limits.

Re: The James Webb Space Telescope is finding too many early galaxies

#88

Post by kolinko »

dave333 wrote: post #47
Tuna-Fish wrote: post #25

Earlier quoted context omitted.

This doesn't work. The universe was opaque for the first few hundred thousand years, even if there is a cycle, we cannot possibly see it.

We are not looking back into the past cycle, but we see mature galaxies that date from the previous cycle.

What you're saying doesn't make sense - not even according to the bizzaro theory you mentioned. Even if there was a previous cycle, there would be no galaxies left from it to witness.

Re: The James Webb Space Telescope is finding too many early galaxies

#89

Post by jhoechtl »

cwkoss wrote: post #14

Is it possible that the 'edge' of universe reflects light? Have scientists been able to conclusively rule that out somehow? Does the universe even have an edge? What is our current understanding of what the boundaries of the universe might be like?

My theory: It's not an edge but we look onto ourselves back in time. As space and time evolves, it's hard to identify as such.

One day we will recognize that we essentially were looking onto space to see ourselves while starring. The last thing is meant metaphorical.

Re: The James Webb Space Telescope is finding too many early galaxies

#90

Post by superjan »

seanw444 wrote: post #29
Tuna-Fish wrote: post #22

Earlier quoted context omitted.

We can't see down to 0 seconds, because very soon after the big bang, the universe was filled with dense, extremely hot, opaque plasma. The closest we can get is the "recombination epoch" [0], which is roughly 370 000 years after the big bang, when, because of universal expansion, the plasma got cold enough for neutral hydrogen to start forming, at which point the universe became transparent. As protons gain electron…

So if we can see CMB in all directions, why do we really even say "the observable universe" as though there could be more matter and more galaxies beyond what we can see? If the maximum of what we can see is implied to be before all galaxies, then shouldn't it be implied that all galaxies that exist can be seen?

Well most physicists assume it is massively bigger than we can see. It is in principle possible that we see nearly all of it, but that would be very coincidental. The only thing we know is that it is at least as big as we can observe, but it could be hundreds of times bigger, 10^100, or even infinite.

There are speculations one could make that imply a minimum size, I recall a reading a prediction of 10^50 times bigger or so.

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