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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

#531

Post by moloch-hai »

foxyv wrote: post #514
moloch-hai wrote: post #288

Earlier quoted context omitted.

> It's one of those non-linear messy quantum things that's a pain in the neck to solve. That is exactly equivalent to "dunno, maybe something".

> That is exactly equivalent to "dunno, maybe something". Yup! It's like understanding the why of weather and people. They are messy and have so many factors you can't account for. It's like saying, why are the clouds shaped like that. You can why your way down, but it's turtles all the way! When it comes to non-linear junk, the why becomes mixed up because the causes are so numerous. There are so many tiny interacti…

It is entirely possible that global warming could tip us into the next ice age, though probably not in our lifetimes.

First you would need a world-wide cloud layer reflecting insolation back without conversion to IR. As the temperature drops, ice forms. When the clouds dissipate, the ice takes over reflecting sunlight out.

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

#532

Post by shagie »

denton-scratch wrote: post #480
sfifs wrote: post #131

Earlier quoted context omitted.

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)

> So such an expansion phenomenon should affect everything uniformly right? Apparently not. As far as I can tell (IANAC) cosmic expansion affects the empty space between galaxies, but not concentrations of mass. Galaxies (and everything in them) are immune to cosmic expansion. I understood that cosmic expansion is a consequence of General Relativity; DE is supposed to explain accelerating expansion. Is that right? Bu…

(I commented on the parent comment... and came back to this one...)

The question of "is the rate of acceleration accelerating"... PBS Space Time

Dark Energy Explained https://www.youtube.com/playlist?list=PLsPUh22kYmNAv1_8MA9-U...

> Want to understand what we know about Dark Energy: the hypothetical form of energy that exerts a negative, repulsive pressure on the universe that effects the energy on the largest scales? Then enjoy this Dark Energy playlist!

And the question is "is the rate of acceleration accelerating?" If so, then make sure you watch "Could the Universe End by Tearing Apart Every Atom?"

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

#533

Post by astrange »

Cthulhu_ wrote: post #419
yipbub wrote: post #413

Earlier quoted context omitted.

Same, but I imagine doing it in a country house with a table looking out into a lovely garden, and a mountain path nearby for long walks thinking about things.

I'm sure there's a catchy phrase for that kind of thing, intellectual cottagecore maybe?

I think that's called "dark academia".

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

#534

Post by throwawaymaths »

rsj_hn wrote: post #293
throwawaymaths wrote: post #284

Earlier quoted context omitted.

He's passed, but jacob bekenstein?

Bekenstein wrote an interesting paper on MOND in 2010 here: https://arxiv.org/abs/1001.3876 But again, the 2017 experimental data [cited previously] in support of Lorentz invariance and the 2016 bullet cluster data in support of dark matter basically killed MOND in the eyes of most researchers. As I said before, nothing wrong with writing papers exploring the consequences of MOND or trying to come up with alternative…

I don't know where you're getting this idea that MOND breaks Lorentz invariance. I've never heard of anyone claiming that that is evidence against mond. Hell, a search of mond and Lorentz invariance turns up your comment as one of the top results.

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

#536

Post by eru »

moloch-hai wrote: post #481
eru wrote: post #385

Earlier quoted context omitted.

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.

Some do. Many don't. Much of Wikipedia is "curated" by retired professors carefully scrubbing mention of anything new that makes their graduate thesis look ill-conceived.

> Much of Wikipedia is "curated" by retired professors carefully scrubbing mention of anything new that makes their graduate thesis look ill-conceived.

What makes you think so? What evidence do you have?

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

#537

Post by b800h »

moloch-hai wrote: post #301
b800h wrote: post #77

Earlier quoted context omitted.

There is a wonderful sequence in the (2nd?) Book of Enoch (~150AD?), where the viewer is transported up through the heavens, past the planets, and finally beyond the stars, and eventually sees the incomprehensible face of God lying behind it all, visible all across the far end of space. So perhaps that? :-)

Great flaming letters spelling out "We apologize for the inconvenience".

Haha, Douglas Adams was nothing if not well-read.

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

#538

Post by mr_mitm »

bmitc wrote: post #505
Beldin wrote: post #484

Earlier quoted context omitted.

The simplest explanation is that there is regular matter which we fail to detect. Not weird, given the huge distances involved - there almost assuredly is mass that we didn't detect (e.g. planets). The point where fairy matter comes in, is that we can guess how bad we could be at not detecting matter. Basically, regular matter that we didn't observe can't explain everything - we would've observed it otherwise.

> The simplest explanation is that there is regular matter which we fail to detect. Not weird, given the huge distances involved - there almost assuredly is mass that we didn't detect (e.g. planets). What is the difference between that and dark matter? > there almost assuredly is mass that we didn't detect (e.g. planets). Don’t planets give off light and thus contribute to the distribution of light observed?

The GP is talking about MACHOs; MAssive Compact Halo Objects. They used to be a valid DM candidate but have been ruled out 20-30 years ago. Planets don't give off any non-negligible amount of light. However, they do consist of baryons (read: atoms) which would contribute to the baryonic accoustic oscillations in the CMB power spectrum, so that's a good probe to set upper limits on baryonic matter in general.

Primordial black holes are a somewhat related candidate; but those are mostly considered ruled out as well. They are not considered baryonic matter.

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

#539

Post by JPLeRouzic »

ngcc_hk wrote: post #527
jquery wrote: post #377

Earlier quoted context omitted.

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…

Epicycles is what Copernicus fought against. Have he also have some I am not aware of ?! Epicircle come about if one consider earth is the Center and some planets sometimes move backwards and then start to move forward again. You do not have that issues with Copernicus. But he made a mistake of using circle. The observation guy using everything rotate around the sun and sun around the earth … a wrong model but the ke…

Not an historian or astronomer but I guess Copernicus' main work is about heliocentrism, but it uses epicycles.

It has to because in his views planets made circles around the sun and at constant speed.

Indeed Copernicus was aware this only could not explain what is observed so he had to introduce epicycles as in Hipparchian, Ptolemaic system.

Circles with epicycles are just an approximation for ellipses, but ellipses could not be introduced without a theory of gravity.

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

#540

Post by JimBlackwood »

bardworx wrote: post #313
JimBlackwood wrote: post #157

Earlier quoted context omitted.

It's in the lines: > The triboelectric effect is very unpredictable, and only broad generalizations can be made. > The mechanisms of triboelectrification (or contact-electrification) have been debated for many years, with possible mechanisms including electron transfer, ion transfer or the material's species transfer. > Recent studies in 2018 using Kelvin probe microscopy and triboelectric nanogenerators revealed tha…

> So, still very much misunderstood. There is an experiment showing the dominant mechanism (so still only explaining a part!) between solid-solid and a generic model proposed that can be used to explain other interactions (solid-liquid, liquid-liquid, etc). This seems like a very large part, no? I mean, we know it works, we get the majority of it, and it doesn’t seem super necessary to spend a lot of dollars and brai…

Sorry for my late response. Anyway:

I get your point. However, this is worked on by researchers who get paid to work on unsolved problems. This is one of them. It's a surprising one, since it looks like such a simple and obvious effect governed by physics we've (seemingly) understood for centuries. Gauss's Laws are from 1773 and much of the work on static electricity is from that era.

So, it's not just an internet debate. Knowing how things work _exactly_ is what scientists do. Getting the majority is not good enough.

And yes, that will often surpass the scale of "Is what we're doing useful?". However, won't know until we find out. Most likely understanding this effect will not bring any revolutionary insight but we should understand it nonetheless. Maybe our understanding will help someone else solve a problem, that solves another problem, that solved another problem, that gives someone a brilliant idea.

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