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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

#211

Post by abtinf »

NovaVeles wrote: post #188
freedude wrote: post #129

Earlier quoted context omitted.

Fields of science should always be willing to change based upon empirical evidence. I think there are several other scientific areas where we know less than we ought. 1. The sub-atomic level 2. The cellular level 3. Ocean biology 4. Geology, particularly effects of earthquakes and volcanic activity 5. Weather patterns over time

I feel for the Weather pattern folk. All of the one I have spoken to over the years are pretty cool. They are trying to model an insanely complex system - oh but thanks to global warming they are struggling to make models that work for longer than a few years because it all keeps changing!

If “it all keeps changing”, which thwarts their attempts to “model an insanely complex system”, then wouldn’t that mean any claim about “global warming” is actually a claim to possessing a priori knowledge?

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

#212

Post by Karellen »

foolswisdom wrote: post #102
largbae wrote: post #85

Earlier quoted context omitted.

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

But what was really the question?

ChatGPT-3: What do you get if you multiply six by nine?

ChatGPT-4: How many roads must a man walk down?

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

#213

Post by xenadu02 »

sfifs wrote: post #131
shagie wrote: post #68

Earlier quoted context omitted.

That rate is "only" approximately 68 kilometers per second per megaparsec. 68 kps isn't that fast (it's about the same speed as the Helios 2 solar probe) and a mega parsec is big distance (3.2M light years). Its that there's a lot of megaparsecs between here and there and the sum of all of those 68 kps is more than the speed of light. The relevant Kurzgesagt : TRUE Limits Of Humanity – The Final Border We Will Never…

So such an expansion phenomenon should affect everything uniformly right? Are we (people /animals) then getting "bigger"? Over time innthe extreme will it cause problems in signal transmission in our own nervous systems (since apparently we have a problem seeing light beyond the observable limit)

The strong nuclear force, electromagnetic force, and even gravity are strong enough to overwhelm the expansion within individual galaxies and even local groups of galaxies.

In other words the expansion of spacetime very very very slightly tries to shift the atoms of your body apart but we can't even detect it because ordinary forces like chemical (electromagnetic) bonds are exponentially stronger - enough to pull things back where they should be. Actually in the current epoch I'm not sure if the expansion is strong enough to shift an electron by 0.01% of its own width let alone move an atom.

Space is really really big so that tiny amount of expansion adds up over long distances.

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

#214

Post by naikrovek »

I don't know why articles are titled like this. it's annoying, though, I'll tell you that

we are finding the exact correct number of galaxies of the exact correct ages; our expectations are wrong, or how we determine what we've found is wrong. generally, our understanding is wrong. not the rest of the entire universe.

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

#216

Post by russdill »

starik36 wrote: post #42

Does this mean that big bang either didn't happen or happened in a different way that we think of it? Or happened far earlier than we think it did? Complete layman here.

Incomplete/unconfirmed data is showing some discrepancies for what our tentative models of the early universe predict. The data could be wrong or misinterpreted, the models could be wrong, incomplete or misinterpreted, or the could be fundamental problems with the very foundations of cosmology. The models we have of early galaxy formation are very incomplete and based on very little data. It's exciting to get data that will discover new things about the early universe and help refine those models.

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

#217

Post by eigenket »

drdeca wrote: post #201
eigenket wrote: post #172

Earlier quoted context omitted.

There are some reasons why cosmologists don't like the idea of a universe that loops back on itself, one is that such a universe can't be both isotropic (the same in every direction) and homogeneous (the same at every point) [edit: while also being flat, as observations seem to indicate it is]. To get a rough idea of why, imagine taking a 1km by 1km square and identifying the opposite sides, you now have a homogeneou…

What’s wrong with it being (topologically) a 3-sphere ? That seems plenty symmetric to me.

Theres nothing massively wrong with it, it's a perfectly plausible model.

The one thing that isn't particularly nice is that spheres have intrinsic curvature, essentially if you draw two parallel lines on a sphere they will eventually touch. We can go and look at astronomical data and see if the universe has any intrinsic curvature that we can see.

People did this and it turns out that from all the astronomical data we have the universe looks incredibly, spectacularly flat. No curvature at all that we can detect. This doesn't mean it isn't a sphere, but it means that if it is a sphere it's a really big one. Much much bigger than the observable universe.

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

#218

Post by russdill »

robg wrote: post #121

Instead of one big bang, imagine an infinite number of big bangs, all colliding on a cosmic scale in time and space. That’s not necessarily a multiverse, but it is a megaverse with universe as the old paradigm.

https://en.wikipedia.org/wiki/Eternal_inflation

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

#219

Post by jfengel »

1970-01-01 wrote: post #169
jfengel wrote: post #104

Earlier quoted context omitted.

It's pretty clear that it's the same at the atomic level as well. The spectra look exactly like they look here. They're red-shifted, but the gaps between the peaks are exactly the same. That comes from the atomic level, the way the electrons are arranged within the atom. If something were different at the atomic level, it would surely change the characteristics of the light they give off. The only way to see what we…

Doesn't spectra come from the Rydberg constant, which is set by several other universal constants? https://en.wikipedia.org/wiki/Rydberg_constant#Alternative_e...

Yes. If any of the constants were different, or the formula were different, we'd see it.

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

#220

Post by peatmoss »

suetoniusp91 wrote: post #192
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…

The simulation gets less cohesive the farther from earth you look.

I was just thinking about video games where vegetation, animals, and hills spring into existence when you get close enough. Far away, and they don't bother to render the little things.

Depending what generation tech we're running on in the parent reality, JWST may be causing a noticeable jump in system load.

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