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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

#281

Post by moloch-hai »

Buttons840 wrote: post #264
azalemeth wrote: post #228

Earlier quoted context omitted.

My favourite example of the intractabilities of some theories is that magnetohydronamics apparently can't predict the formation of streamer jets when you put your finger on a kid's plasma ball – i.e. the main point of the toy is beyond the most advanced theory that lies behind NIF, JET, ITER, etc...

At this point in the thread, I'm wondering if we do a disservice to physics students by making it appear we have it all figured out.

It is easy for children to come up with questions for biologists that none can answer, and that none has even tried to answer.

Biologists are almost unique among scientists in being happy to say how little they still know about their subject. Up until last year nobody had thought to see whether anything eats viruses! Turns out some do.

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

#282

Post by thom »

make3 wrote: post #34
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.

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?

Think of the universe as some sort of information system. The speed of light caps the rate at which information propagates, which is a desirable or at least necessary property at scale. But there’s some discrete substrate underlying that propagation of information. That substrate can multiply, like inserting nodes in a graph or empty spaces in a linked list. That makes it longer to traverse from one end to the other. The rate of propagation stays the same but the map keeps changing.

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

#283

Post by [deleted] »

rsj_hn wrote: post #267
6nf wrote: post #256

Earlier quoted context omitted.

MOND is not compatible with all observations but neither is dark matter. A lot of scientists think MOND is a better explanation than a new particle that we've not yet observed. Have a look at Sabine Hossenfelder's work for some of those arguments.

Which researchers (as opposed to pop-sci pundits) think MOND is a better explanation than Dark matter? That is a very, very fringe alt-science view that so far exists in various pop-sci blogs and informal youtube discussions, rather than in mainstream conferences, journals, and research centers. I'm not saying it's bad to speculate or write whimsical blog articles about these topics, there's lots of room for creative…

[deleted]

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

#284

Post by throwawaymaths »

rsj_hn wrote: post #267
6nf wrote: post #256

Earlier quoted context omitted.

MOND is not compatible with all observations but neither is dark matter. A lot of scientists think MOND is a better explanation than a new particle that we've not yet observed. Have a look at Sabine Hossenfelder's work for some of those arguments.

Which researchers (as opposed to pop-sci pundits) think MOND is a better explanation than Dark matter? That is a very, very fringe alt-science view that so far exists in various pop-sci blogs and informal youtube discussions, rather than in mainstream conferences, journals, and research centers. I'm not saying it's bad to speculate or write whimsical blog articles about these topics, there's lots of room for creative…

He's passed, but jacob bekenstein?

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

#285

Post by kortex »

darkerside wrote: post #266
Sharlin wrote: post #253

Earlier quoted context omitted.

The usual hypothesis is that a microscopic layer of the surface melts, not because your shoes are warm, but because of the pressure. But the pressure is not enough to do that. That said, as anyone who has been in icy conditions can attest, it is clear that ice at ~0° C is vastly more slippery than at, say, -20°C.

My understanding is that, at the borders, master is constantly changing between its states. A boiling pot has water molecules turning to steam, as well as vice versa. It just has more of the first probabilistically. Maybe the same happens with ice and water.

That's more or less it, as far as I understand. There's the hexagonal lattice of solid water ice, where hydrogen bonds form a 3D tetrahedral structure which is very stable. At the boundary, there are no molecules "above" the solid latice, so those water molecules are held less tightly. The exact dynamics are challenging to predict because we can't exactly see what's going on (most simulation based).

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

#286

Post by WXLCKNO »

Spkeat wrote: post #278

This can further reinforce the idea that the unobservable universe was always there and that the big bang is only a pattern of movement of the cluster of galaxies and it is only the information that has managed to arrive from our position.I want to see how big bang theory falls into an optical illusion.

I don't know which idea is harder for me to conceptualize.

That something has always existed or that it came to exist out of nowhere-ish.

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

#287

Post by yreg »

tuatoru wrote: post #273
yreg wrote: post #244

Earlier quoted context omitted.

Earth came quite late to the party and it spawned life relatively soon after. That's why it's strange we haven't discovered any Dyson spheres/swarms (in any galaxy). Either life is indeed absurdly rare, or Dysons are impractical for some reason, or there is a way to mask heat.

Earth life uses lots of different elements - at least two generations of supernovas required. Not really that late if you allow for that.

Didn't that happen within like the first 2B years? First Sol-like systems were I think at 5B years, which would still make Earth ~3B years late to the party.

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

#288

Post by moloch-hai »

foxyv wrote: post #196
gwd wrote: post #143

Earlier quoted context omitted.

> You mean dielectric moments and static electricity? You're confusing what with why . My understanding is that everyone knows it has something to do with electrons collecting on the balloon; but nobody quite knows why rubbing rubber against hair causes the electrons to do that.

I think I got confused because I was thinking about why it stuck to the wall, rather than why it accumulated charge. I know why electrically charged objects stick to things. The why of how they got like that is a bit different as you mentioned. Triboelectric effect is spooky, but there are some theories. It's one of those non-linear messy quantum things that's a pain in the neck to solve.

> 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".

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

#289

Post by mikepurvis »

pmichaud wrote: post #171
mikepurvis wrote: post #106

Earlier quoted context omitted.

I think it's a bit more subtle than whether it can synthesize , because clearly it can produce seemingly new work. But what it definitely cannot do is seek new abstractions . It can't be curious about an inconsistency and probe its own knowledge for possible resolutions, or design an experiment that might shed further light in an unknown area. It can't even play a board game after ingesting the rules to it, much less…

I kind of feel like _all it can do_ is seek new abstractions. It’s clustering the data into what you might think of as “concepts,” even though we haven’t made all that much progress on interrogating those concepts directly. I just think clustering concepts by their latent relationships is sort of what abstraction is.

Hmm, interesting. I feel like that clustering/grouping part is like... the first stage on the way to finding an abstraction, but if all you've done is that part of it, then you haven't reasoned about what the abstraction is, or extrapolated out to a new hypothesis, or grappled with the other consequences of the grouping.

Thinking of mathematics, an abstraction is only as valuable as what it can tell us about the underlying system— a laplace transformation into the frequency domain isn't particularly interesting unless we either a) happen to care about some frequency domain property of the function, or b) we can manipulate the transformed function and then un-transform it afterward, yielding a novel insight in the original time domain.

My layman's assessment is that the current state of the art for machine cognition is about on the level of identifying that such a transformation might be possible, but not actually applying it or doing anything about it, much less unapplying it afterward.

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

#290

Post by SV_BubbleTime »

WXLCKNO wrote: post #286
Spkeat wrote: post #278

This can further reinforce the idea that the unobservable universe was always there and that the big bang is only a pattern of movement of the cluster of galaxies and it is only the information that has managed to arrive from our position.I want to see how big bang theory falls into an optical illusion.

I don't know which idea is harder for me to conceptualize. That something has always existed or that it came to exist out of nowhere-ish.

I suspect this is why simulation theory is popular.
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