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The James Webb Space Telescope is finding too many early galaxies

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381–390 of 547 posts

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

#381
Some more interesting food for thought:

>The classical big bang cosmological models describe gravitation by Einstein’s general theory of relativity. These models are able to treat the matter content of the universe quantum mechanically where appropriate, but they do not take into account the interplay of quantum theory and gravity.... The earliest universe was presumably quantum mechanical through and through, and we can no longer describe its initial conditions in a classical language. We must instead treat the whole early universe as a quantum system and formulate its initial conditions in the language of quantum mechanics.... Quantum gravity theorists have not shied away from the challenge. At present there are some half a dozen contenders...."

https://www.einstein-online.info/en/spotlight/quantum_cosmo_...

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

#382
post #4

Can someone explain to me what would be behind the galaxies if we could see it, to the point of 0 seconds after the big bang? Black, white, is it even possible?

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…

> the uniform ultimate backdrop we have when looking in any direction

Is the CMB exactly uniform in every direction? Or is this early light slightly more redshifted when we look up versus when we look down or left or right? Does the oldest light we see in any given direction vary slightly in color?

I'm imagining the universe expanding as a sphere from a central point, but we're located off-center. Wouldn't the early infrared photons emitted from the other side of the central point of expansion from us be observed by us now as a slightly different color than the early infrared photons emitted closer to the edge of the early expanding universe?

A rabbit hole of questions: - When did space start expanding? - Did it have to rapidly expand for 400k years as extreme forces propelled matter apart? - Was that expansion faster or slower than the current expansion of space between galaxy groups? - Is expansion uniform across the universe? - Or is expansion slower closest to the original center of the universe? - Maybe there's a central point in the universe that's not moving relative to a reference frame outside our universe? - Is space discrete or continuous? - As space expands do new "units" of space appear between units of space that have grown farther apart? - If not, wouldn't physics work differently for areas of space where the units of space have grown farther apart than areas of space where the units of space aren't as far apart?

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

#383
post #377

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…

If MOND completely described observable phenomenon it would supplant dark matter, but it doesn't. MOND still requires dark matter, just less of it. Or, to quote Milgrom, "some standard matter in some form that has not been detected"[1]. Which, IMHO, is nearly isomorphic to DM as far as statements go.

So until we figure out what the missing mass is, MOND is widely viewed as an unnecessary complication. There is missing mass, if we figure out the nature of DM or discover this hitherto unknown "standard matter" then we can talk about modifying universal gravitation.

[1]: https://web.archive.org/web/20160721044735/http://www.astro....

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

#384
post #331

Earlier quoted context omitted.

Carbon dioxide is actually a relatively weak greenhouse gas. At least compared to water vapour, or even methane. Btw, CO2 does 'magically' disappear. Into the oceans. Alas, from what I've read it'll take about 2,000 years to do so. > [...], but the general direction of travel cannot be seriously disputed without arguing against the above simple facts. I don't want to argue against global warming, but I want to argue…

I understood their point to be that that based on our understanding of basic physics and chemistry, the energy balance is such that the Earth system is gaining energy, and that this will lead to increased temperatures among other things. Certainly there are all kinds of complexities about how that energy will be distributed and what the effects will be, but just in terms of a simple energy balance model based on well…

> Certainly there are all kinds of complexities about how that energy will be distributed and what the effects will be, but just in terms of a simple energy balance model based on well understood physics, it would be difficult to make the case that warming won't happen.

There are lots more effects. When lots of volcanoes erupt, we also see more CO2, but we see the climate cool down.

That's because the effect of the CO2 is outweighed by other factors. But exactly that there are lots of factors is my point.

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

#385
post #329

Earlier quoted context omitted.

> Biologists are almost unique among scientists in being happy to say how little they still know [...] Citation needed. > Up until last year nobody had thought to see whether anything eats viruses! Turns out some do. Nah, lots of things eat viruses. It's nothing unusual at all. You eat viruses, I eat viruses. They are everywhere, after all. The novel finding was a critter that lives / can live solely on viruses.

> Citation needed How could you possible find a citation for that? It’s not even pretending to be a scientific or totally objective claim. Asking for a citation for this type of statement is no way to have a discussion. Do you not see why?

Eh, 'Citation needed.' was my admittedly somewhat snarky way of calling bullshit.

Most any scientist will happily babble all about the stuff they don't know yet in their discipline, because that's exactly where the excitement lies for them.

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

#386
post #329

Earlier quoted context omitted.

> Biologists are almost unique among scientists in being happy to say how little they still know [...] Citation needed. > Up until last year nobody had thought to see whether anything eats viruses! Turns out some do. Nah, lots of things eat viruses. It's nothing unusual at all. You eat viruses, I eat viruses. They are everywhere, after all. The novel finding was a critter that lives / can live solely on viruses.

> Nah, lots of things eat viruses. It's nothing unusual at all. You > eat viruses, I eat viruses. They are everywhere, after all. When an engineer walks in front of an idling jet engine you don't say the jet eats viruses.

To be more precise, viruses are just made up of proteins and DNA / RNA. Your normal digestion that can handle proteins and DNA/RNA from animals, plants etc doesn't have any more problem breaking down virus proteins into amino acids and absorbing them.

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

#387

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.

> 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…

I'm still not convinced that the expansion of the universe is accelerating based on current evidence.

That argument largely comes from supernovae appearing dimmer than we think they should, and more distant things appear more red and it looks that way in any direction we look. But the thing is, we sometimes calculate how distant things are based on redness, so it's kind of circular reasoning.

Sure we have other things which help gauge distance, like brightness and periods of Cepheids, but if you look into history on Cepheids, the association that brightness is directly related to periods was built upon an assumption that the Cepheids in a galaxy were roughly all the same distance away. That may seem probable, but it isn't a given, as galaxies can be at various angles to our perspective, as well as being different size in various dimensions. It also assumes that it is impossible for fake Cepheids to exist, which might even confer a reverse association. How could we know if we're looking at false Cepheids vs real Cepheids, and that there's not multiple types of Cepheids with different causes for pulsations at various brightnesses?

Next you have to consider movement is relative. It's entirely possible a brighter galaxy is moving 2x faster away from us, than a dimmer galaxy that is actually closer to us. Yet this is hardly considered from distance calculations.

Lastly, people also say the Big Bang is not an explosion of matter moving outward to fill an empty universe, but rather an expansion of space between things. IMO, this is mostly just a model, a way of viewing things. The thing is, you can still look at things from normal intuition (of say an explosion), and it still conforms that definition (ie it's objects moving in space over time, vs it's space filling in between objects over time). And so, if looking further into the galaxy, means looking further in time, the dynamics of an explosion suggests that those galaxies will be moving faster away from us. As the outmost debris of an explosion, is the fastest moving debris of an explosion, and speed between two pieces of debris, is highly associated to their relative positions and tends to increase as distance between them increases, even regardless of where they are in an explosion. So even if further galaxies are indeed moving faster away from us, and it is faster the further we look, and looks that way every which way, I don't see why this would necessarily mean the expansion of the universe is accelerating. As it appears to me, it can be predicted by conventional (non-accelerating) explosion dynamics.

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

#388

Some more interesting food for thought: >The classical big bang cosmological models describe gravitation by Einstein’s general theory of relativity. These models are able to treat the matter content of the universe quantum mechanically where appropriate, but they do not take into account the interplay of quantum theory and gravity.... The earliest universe was presumably quantum mechanical through and through, and we…

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

#389
post #141

This is good. If we merely confirm what we expect to see, then we don't learn anything new.

Not so sure. If we're not early ourselves, the likelihood that the universe is swimming in intelligence -- if not already part of an enormous computational fabric -- is higher. That naively seems like it would place an upper limit on Earth-originated intelligences.

Would that be such a bad thing?

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

#390
post #359
post #275

Earlier quoted context omitted.

So much this! There’s surely a huge argument that all of scientific education is a massive disservice. The point should be to learn and appreciate the method or process of scientific investigation of uncertain and mysterious or hard to understand phenomena. Instead we get dogma as a proxy of measuring intelligence with little regard for what the fundamental tools are of being a scientist. I’ve gone all the way throug…

> There’s surely a huge argument that all of scientific education is a massive disservice. > If the general public is to benefit from education and pass that benefit into their society (that’s the point right), it needs to be more than soon to be forgotten and often useless fallacies. I realize this is hyperbole, but still I think it's obvious that there is more than soon to be forgotten and often useless fallacies.…

Agree. I’m guilty of descending to hyperbole at times!

Nonetheless, while I agree with your pushback, I do wonder how much utility there is in the “dogma” approach. There’s a lot of “facts” being thrown around in education, from what I’ve seen, that are often forgotten or become vague memories. How much better would it be to focus on skills and practice and concepts? Especially in the digital age where a fact is easily discoverable, provided one has the appropriate research skills.

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