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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

#61

Post by HideousKojima »

lalalandland wrote: post #24
dave333 wrote: post #7

[flagged]

I watched a few videos about variable speed of light. I know nothing about this but it is fun to ponder different explanations for Dark Matter, Dark Energy etc.

You may like my silly theory (made with zero evidence) to bring back the Big Crunch Theory. Imagine that spacetime is a sphere, and the Big Bang happened at the "north pole" so to speak. All matter will eventually meet back together and recombine at the "south pole" after which a new Big Bang will happen. Absolutely zero evidence for my idea and it's probably impossible to prove anyway but it's fun to theorize.

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

#63

Post by aeneasmackenzie »

sebzim4500 wrote: post #54
JetSetWilly wrote: post #6

Earlier quoted context omitted.

This is not unusual. There's many predictions made by MOND ahead of the fact that are borne out by reality. But don't worry - dark matter will be "retrofitted" so that it fits the facts and everybody will suffer collective memory loss again. Edit: see for example table 1 on page 12 here: https://arxiv.org/pdf/2110.06936.pdf from a review of prior expectations by both MOND and dark matter vs how they turned out agains…

Am I understanding that paper correctly that their suggested solution to explain the Bullet Cluster using MOND is too introduce an additional kind of matter which can not be detected on earth and doesn't interact with light (namely sterile neutrinos)? Is this satire?

"dark matter but not as much" is still an improvement if you replace it with something better. If MOND predicted these observations and LCDM didn't it's reasonable to say that it is better.

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

#64

Post by function_seven »

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.

I vote we bring back “aether” as a valid term. The aether is stretching everywhere, and in so doing it spreads distant things away faster than light can overcome.

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

#65

Post by GrantS »

oblio wrote: post #26
pwatsonwailes wrote: post #18

Earlier quoted context omitted.

Without getting into lots of detail, this is basically correct. It's why we talk about the observable universe. There's lots of stuff we can't see because the light from it won't reach us.

I was thinking about something weird right now. We don't (can't?) even know if there weren't multiple Big Bangs, right? I.e we're just in a specific "universe" we can observe, but maybe several of these are just side by side, not necessarily parallel as in parallel realities.

Eternal inflation: https://en.m.wikipedia.org/wiki/Eternal_inflation

A more reader-friendly explanation: https://medium.com/amazing-science/if-inflation-is-true-then...

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

#66

Post by 8note »

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 wouldn't be surprised if there's a hawking radiation equivalent for that edge, but the wavelength is on the order of the size of the universe, so basically impossible to measure

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

#68

Post by shagie »

Twisol wrote: post #45
SkyMarshal wrote: post #30

Earlier quoted context omitted.

> because the light from it won't reach us. This is one of the most interesting aspects to the universe. It's not, "because the light from it hasn't reached us yet but is on the way and will get here eventually." Rather it's that the rate of expansion of the universe is accelerating, so that we're moving away from parts of it faster than its light can cover the distance to us. It will never reach us. That's mindboggl…

> Rather it's that the rate of expansion of the universe is accelerating, so that we're moving away from parts of it faster than its light can cover the distance to us. From my understanding, it's not that we're moving away from parts of the universe, but that the distance between us is growing so fast that light sent from one part will find that after traveling toward us for some amount of time, the remaining distan…

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 Cross - https://youtu.be/uzkD5SeuwzM

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

#69

Post by fknorangesite »

micromacrofoot wrote: post #50
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?

I did a wrong, ignore me

This is exactly wrong: c is the one speed that is constant to all observers.
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