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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

#311

Post by TillE »

abtinf wrote: post #211
NovaVeles wrote: post #188

Earlier quoted context omitted.

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?

We know very well how carbon dioxide interacts with infrared radiation (easily tested with an IR spectrometer), and we know human activity releases enormous quantities of carbon dioxide into the atmosphere, which does not magically disappear.

Precise predictions are hard, but the general direction of travel cannot be seriously disputed without arguing against the above simple facts.

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

#312

Post by m463 »

emptybits wrote: post #272
vl wrote: post #198

Earlier quoted context omitted.

>Certainly there are many unexplained effects in solid state physics Wait for it… Why ice is slippery? Usual explanation is completely incorrect. Actual semi-conclusive research just recently happened.

I had to look that up. Here's research[1][2] from 2019 about "why ice is so slippery", including some of the apparent surprises. I dunno. I'm not a physicist so some of the surprises seem like very minor things to me. Spoiler: According to this research, ice is slippery because of a thin layer of water. (As we expected, no?) But the water layer is 1) thinner than expected, 2) more viscous than expected, and 3) contai…

I remember listening to joe rogan when he interviewed neil degrasse tyson and he had some fascinating insights into the behavior of water with relation to pressure and temperature.

I can imagine ice on an iceskate wanting to be solid, but because that takes up too much space it becomes a liquid instead.

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

#313

Post by bardworx »

JimBlackwood wrote: post #157
Eduard wrote: post #140

Earlier quoted context omitted.

Reading https://en.m.wikipedia.org/wiki/Triboelectric_effect , I have the impression the mechanisms are not _that_ poorly understood, at least from my layman's perspective.

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 brain power to satisfy an internet debate on a theory of rubbing a balloon on one’s head.

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

#314

Post by bbreier »

whaaswijk wrote: post #308
tommoor wrote: post #299

Earlier quoted context omitted.

Much like god, that just pushes the question up one level

While I agree that simulation theory pushes the question up a level, that is not the case for the God of classical theism.

Ok, I'm curious. How does the explanation for everything's existence being "God did it" not simply push the question up a level to wondering how to explain God's existence?

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

#315

Post by pmichaud »

mikepurvis wrote: post #289
pmichaud wrote: post #171

Earlier quoted context omitted.

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 unde…

I think I get the gist of your point which I would handwavily summarize as “there is no there there,” which I agree with. But I’m thinking that in terms of functionality, there is no real distinction here. Like If I train a model to do video game physics, and reward it for getting the tank shell missile to land on arbitrary targets, then in some sense the system must have an abstraction of gravity or at least parabolic movement or at least a functional equivalent of that, and it must be able to “hypothesize” about the consequences of its model because that’s what it needs to do in order to hit the target, ie, “everything I’ve seen before leads me to believe tank missiles move like so, therefore if I apply the following forces, it should hit the goal”—the degree to which it wins at this task is exactly the degree to which it can form working models of its environment and reason about the cause and effect of the actions it can take. But of course all those words in the previous sentence are wrong because it’s not exactly doing any of that, just something functionally equivalent and automatic.

Maybe we disagree about whether that last point means it can meaningfully “do abstraction” or not.

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

#316

Post by 10g1k »

A lot of academic/scientific belief is based on ignorance. Hear me out.

The entire academic/medical establishment believed the appendix was "just a vestigial organ" which served no purpose. It was taught in every university, in every textbook. Every medical professional knew it was a fact. Why? Because they had not identified a purpose. In their ignorance, they adopted the position "I don't know what it does, therefore I can state as a fact that it does nothing." Except it turned out they were all wrong, for a very long time.

The appendix is not the only example of that mentality.

The same has occurred when it comes to estimates of the age of the universe.

When the most powerful telescope could see N lightyears, people believed the universe was N years old. Tiny gains or new images using that telescope adjusted the estimate to N.fraction years.

When the most powerful telescope could see 2N lightyears, people believed the universe was 2N years old. Tiny gains or new images using that telescope adjusted the estimate to 2N.fraction years.

When the most powerful telescope could see 3N lightyears, people believed the universe was 3N years old. Tiny gains or new images using that telescope adjusted the estimate to 3N.fraction years.

This happens every time. Yet astronomers and cosmologists refuse to learn the lesson, and keep repeating the same mistake.

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

#318

Post by mixmastamyk »

UltraViolence wrote: post #189

So there could've been civilizations that are literally BILLIONS of years ahead of us? Imagine what these people know about the universe! This reminds me of the Star Wars lead-in: "A long long time ago in a galaxy far far away." It really could've happened you know!

The first ones are beyond the rim now.

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

#319

Post by WalterBright »

sebzim4500 wrote: post #98
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…

I think this says less about cosmology and more about the incredibly effectiveness of the standard model in the regime we can test directly on earth. If we compare ΛCDM to most other scientific theories it doesn't look so bad in terms of discrepancies. Certainly there are many unexplained effects in solid state physics, there isn't even an accepted explanation for why rubbing a balloon on your head makes it stick to…

> there are many unexplained effects in solid state physics

Looks like there is plenty of opportunity for newly minted physicists to make their names and careers!

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

#320

Post by flockonus »

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.

Calling mental models "laws of physics" is the biggest linguistic disservice to science itself, so in a way, yes.
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