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The James Webb Space Telescope is finding too many early galaxies

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

#491

Post by UltraViolence »

scotty79 wrote: post #270
UltraViolence wrote: post #189

So there could've been civilizations that are literally BILLIONS of years ahead of us? Imagine what these people know about the universe! This reminds me of the Star Wars lead-in: "A long long time ago in a galaxy far far away." It really could've happened you know!

I don't know. Life needed almost 5bn years to get to this point on Earth. Let's say we lucked out and it almost always takes 3 times as long. Then we look like early birds in the Universe. What's more, earlier solar systems had a bit boring chemistry. We need a lot of supernova made stuff to really function so this narrows the time window. You might think that near galactic core there's a lot of really cool stuff mad…

You don't know that. Life might be possible with simpler chemistry too.

Chemistry was sufficient 100 million years ago for intelligent life to evolve, so some other solar system could've easily have had intelligent life for that long or even longer if they were lucky.

Our lives have changed beyond recognition in the last 500 years. Imagine a civilization that's thousands, tens of thousands or even hundreds of thousands of years ahead of us.

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

#492

Post by Calavar »

reptation wrote: post #110
Maursault wrote: post #76

Earlier quoted context omitted.

> The universe is 13.7b yo, but due to acceleration of expansion, if you could "teleport", it's actually currently 93b ly across. So we're already in a bubble within a greater universe that we'll never be able to escape This number, the age of the universe, has changed a few times since I learned to read 45 some years ago. What are the chances that this isn't really "the" universe, but what we know as the observable…

It's worth pointing out that there is a minority of physicists who don't accept the Big Bang as proven beyond doubt. An alternative theory would be a 'steady-state' universe which, as you suggest, would be much older than the ~14 BYO age. If the medium of space itself dispersed light for instance, red shifts might be observed that explain the astronomical data.

> If the medium of space itself dispersed light for instance, red shifts might be observed that explain the astronomical data.

This is called tired light theory. There's a professor of physics at UCLA who has a good breakdown of some of the major flaws with that theory.

https://astro.ucla.edu/~wright/tiredlit.htm

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

#493

Post by raxxorraxor »

User23 wrote: post #155
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…

There's a joke that calling Computer Science Computer Science is like calling Astronomy Telescope Science, but part of what makes it funny is the ring of truth to it. Our instruments really do limit our observations. The advantage Computer Scientists have is that we can glimpse a world of Platonic Forms[1], where Functions, and Sets, and Information exist, or something close enough for government work, merely through…

Astronomers probably should go on the quest for immortality since otherwise you are basically condemned to look at a still image. Even if that image contains a story from the earliest universe until now. It is a million states, but no real process.

What I find so fascinating is that the observations are still quite precise. How do you know the outer rims are rotating too fast? Couldn't this be some gravitational lensing and stars are actually much closer to the core than they appear?

How do you even begin to estimate the mass of a galaxy? How do you weight the behavior of a disc and combine it with keplers law to even see that something is wrong here? As a layman I would be perfectly happy with how galaxy are rotating... I find it fascinating that much is so precisely determined that we have to miss something.

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

#494

Post by gitfan86 »

andrei_says_ wrote: post #335
gitfan86 wrote: post #255

Earlier quoted context omitted.

We have known that the current model of physics is wrong for a long time. But the main focus has been on math. "If only we could figure out this formula, then we would understand everything" It seems much more likely that we are not missing a formula but a basic understanding of reality. Much like the early astronomers trying to find a formula for the movement of the sun and planets that put Earth at the center of th…

I really like this comparison. But isn’t the case with modern physics that we are getting something like 8 of 10 things right? So that’s a lot of correct triangulation - and throwing the current understanding out would throw all of that away - and potentially rearrange things.

The Ptolemaic System was also mostly correct at predicting the movement of celestial bodies.

https://en.wikipedia.org/wiki/Geocentric_model#Ptolemaic_sys...

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

#495

Post by moffkalast »

jquery wrote: post #377
idlewords wrote: post #325

This was predicted by astronomer Stacy McGaugh on his super interesting blog as a natural consequence of modified Newtonian dynamics ( https://tritonstation.com/2022/01/03/what-jwst-will-see/ ). McGaugh came to support MOND over dark matter reluctantly for just such reasons—MOND routinely predicts things in advance that dark matter struggles to justify ex post facto, usually by adding additional moving parts to the m…

It seems to me, as a layperson, if MOND was hypothesized first, it would be the dominant theory. It’s so elegant and simple with so much explanatory power. However, because it was hypothesized much later, the fact it matches past predictions is given no weight, despite its simplicity. I think this is a bit of a mistake. I believe that simplicity itself is evidence. Dark matter theory is starting to feel like the epic…

I was pretty convinced that dark matter is made up nonsense and that RelMOND is probably correct, but then I learned of the Bullet cluster.

https://en.wikipedia.org/wiki/Bullet_Cluster#Significance_to...

Two clusters collided, with most of the observable objects being just past the middle point right now, however most of the mass seems have already shot way out to the edges, as if it passed right through everything. It's pretty hard to explain with anything else other than that there's something there that has mass yet can't interact with anything else that passed through everything when the collision happened. Adjusting equations doesn't really work in this case, there must be something physically there.

I'm not sure why this isn't mentioned first thing every time in dark matter discussions because it's literally the only thing that's pretty hard evidence imo.

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

#496

Post by scotty79 »

UltraViolence wrote: post #491
scotty79 wrote: post #270

Earlier quoted context omitted.

I don't know. Life needed almost 5bn years to get to this point on Earth. Let's say we lucked out and it almost always takes 3 times as long. Then we look like early birds in the Universe. What's more, earlier solar systems had a bit boring chemistry. We need a lot of supernova made stuff to really function so this narrows the time window. You might think that near galactic core there's a lot of really cool stuff mad…

You don't know that. Life might be possible with simpler chemistry too. Chemistry was sufficient 100 million years ago for intelligent life to evolve, so some other solar system could've easily have had intelligent life for that long or even longer if they were lucky. Our lives have changed beyond recognition in the last 500 years. Imagine a civilization that's thousands, tens of thousands or even hundreds of thousan…

> Life might be possible with simpler chemistry too.

Yeah, but we since we know of only one instance of life developing we don't really know what's actually possible and what only might be possible.

> Chemistry was sufficient 100 million years ago for intelligent life to evolve, so some other solar system could've easily have had intelligent life for that long or even longer if they were lucky.

What I'm saying is that time it took life to develop on our planet is so close to the age of the universe (not even one order of magnitude of difference) that it's entirely possible that we were the lucky ones and the next intelligent life (or even eukaryotic life) in the universe won't show up for another few billions of years. Although it will inevitably show up.

> Our lives have changed beyond recognition in the last 500 years. Imagine a civilization that's thousands, tens of thousands or even hundreds of thousands of years ahead of us.

However technological capabilities of life didn't change at all in last 4 bn years despite it being in control of the whole planet for that long. Technology seems to need a really long runway to fly off.

Another thing is that once technology kicks in as you noticed it develops incredibly fast and it influences the environment at the same speed. And life doesn't really like fast changes to environment so the technology in hundred thousand years might make this world completely unlivable.

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

#497

Post by narag »

cryptonector wrote: post #408
narag wrote: post #302

Earlier quoted context omitted.

The funny thing is that since we've been observing the universe for so little time, and we're so small, most of the evidence for the big bang and expansion is not direct , but a chain of deductions. I mean that we can't observe the expansion because we can't really triangulate at galactic scale. If there is another reason the light from distant galaxies turn to red, kind of a long-distance light fatigue, we couldn't…

> If there is another reason the light from distant galaxies turn to red, kind of a long-distance light fatigue, we couldn't really know. It's not just red shift that demands an explanation, but also that the sky (space) is dark. If space wasn't expanding then the skies would be bright white. Another thing is the second law of thermodynamics, which very strongly implies a lot of standard cosmology. Of course, standar…

It's not just red shift that demands an explanation, but also that the sky (space) is dark. If space wasn't expanding then the skies would be bright white.

Another thing is the second law of thermodynamics, which very strongly implies a lot of standard cosmology.

Don't you feel that these evidences just make a case from models checked in small scales and tell the whole universe what it should do?

I don't mean the reasoning is incorrect or unwarranted, just that there could be alternative explanations that involve unknowns.

Of course, standard cosmology could be all wrong, but these deductions are quite solid as far as the physics that we know today.

When applying Occam's razor, you try to minimize entities and simplify. But what appears simpler for a physicist is sometimes surprising for the rest of us. The equations don't work as expected? No problem, let's say that the entire universe is expanding or, even better, that space is expanding. Or that all the universe was at some moment in the space of a tennis ball. Or that big bang happened everywhere at the same time...

While some explanation fits the maths, it doesn't matter if it's totally alien to common sense. Actually I find all those weird explanations strangely appealing, they give me a sense of wonder and empowerment. Cosmology feels like a superpower :)

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

#498

Post by medstrom »

__alexs wrote: post #470
emptybits wrote: post #272

Earlier quoted context omitted.

I had to look that up. Here's research[1][2] from 2019 about "why ice is so slippery", including some of the apparent surprises. I dunno. I'm not a physicist so some of the surprises seem like very minor things to me. Spoiler: According to this research, ice is slippery because of a thin layer of water. (As we expected, no?) But the water layer is 1) thinner than expected, 2) more viscous than expected, and 3) contai…

Ice isn't slippery, water is. If anything I'd say ice is actually pretty sticky. A very cold ice cube will easily stick to your skin.

That's just because your skin has water molecules that freeze on contact with the ice cube. If you use tongs to put an ice cube on your desk, it doesn't stick at all, right? And the friction is very low so it's easy to kick away -- things like a leather wallet stick much better to your desk.

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

#499

Post by narag »

habibur wrote: post #416
ash wrote: post #409

Earlier quoted context omitted.

Why would it be bright white?

Any straight line you draw from earth to any direction in the sky will then reach a star.

Any straight line you draw from earth to any direction in the sky will then reach a star.

Only if you think that there is infinite matter, all of it forming the same kind of stars, uniformly spread over the infinite space and there is no unknown form of atenuation for waves traveling millions or billions of years light.

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

#500

Post by moloch-hai »

eru wrote: post #488
moloch-hai wrote: post #479

Earlier quoted context omitted.

You wrote it, but it was what we all understood already, making writing it nothing but an exercise in snark.

Not sure. Eg creatures that eat plastic are still news, even if plastic is not their sole diet.

Yet, you are eating plastic every day.
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