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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

#201

Post by drdeca »

eigenket wrote: post #172
chrisweekly wrote: post #119

Earlier quoted context omitted.

also (citation needed, this is from memory from university cosmology classes over 20y ago, maybe misremembering or info out of date) the shape of the universe may be less like a sphere and more like a toroid, or a multidimensional moebius strip. so (hand-wavy, impossible IRL but maybe illustrative / fun to think about) if you could freeze time and look far enough in one direction, you'd see the back of your own head.

There are some reasons why cosmologists don't like the idea of a universe that loops back on itself, one is that such a universe can't be both isotropic (the same in every direction) and homogeneous (the same at every point) [edit: while also being flat, as observations seem to indicate it is]. To get a rough idea of why, imagine taking a 1km by 1km square and identifying the opposite sides, you now have a homogeneou…

What’s wrong with it being (topologically) a 3-sphere ? That seems plenty symmetric to me.

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

#202

Post by alfor »

moffkalast wrote: post #160
jpttsn wrote: post #126

Earlier quoted context omitted.

At that point why not call it “witchcraft;” a sciencey word for something is not an explanation.

Clearly you've never recalibrated the thermal interferometery scanner so you can reverse the polarity of the neutron flow in the isoneutronic pulse wave carrier.

You need a plumbus for that.

Everyone need one.

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

#203

Post by foxyv »

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!

What's even crazier is that those civilizations could have built and advanced for a 100 million years and we would never know about it because they are so far away. The light from Canis Major, our closest galactic neighbor, is older than our civilization (25,000 years). The average distance between galaxies is 1 million light years. For all we know, there have been billions of civilizations that have lasted longer than the lifetime of our solar system and we haven't even seen the light from them yet.

The universe is huge!

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

#204

Post by Twisol »

sfifs wrote: post #131
shagie wrote: post #68

Earlier quoted context omitted.

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…

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)

Gravitational attraction still dominates on even fairly large scales, and chemical bonds absolutely dominate over anything expansion could possibly do -- it would contribute an incredibly light force opposing any bonds. So no, we (and our galaxy) are in no danger of being inflated from the inside by space itself.

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

#205

Post by zelphirkalt »

dalbasal wrote: post #147
kibwen wrote: post #58

Earlier quoted context omitted.

> 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. It's actually even worse than that. Because of the accelerating expansion of the universe, over time the part of the universe that we can observe will get smaller, allowing us to see less and less of it. Eventually, all that we…

So galaxies are falling off the edge of the universe never to be seen again?

I know it is considered increasingly unlikely, but: What a parallel to flat Earth ideas people had (...) hundreds of years ago, until they realized we are on a sphere. Maybe in a few hundred years people will laugh about our limited ideas of the universe as well.

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

#206

Post by cypress66 »

lp4vn wrote: post #185
Tuna-Fish wrote: post #22

Earlier quoted context omitted.

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…

What I'm going to ask you is completely dumb, but keep in mind I don't know much of physics. If my understanding is correct, when mass gets dense enough inside, a star you have a black hole, that would be like a hole in the fabric of space time. Ok, we have black holes in the contemporary universe. So how was the primordial universe a ball of dense, extremely hot, opaque plasma without becoming a huge black hole?

I have no idea about cosmology, but I think maybe that if this dense matter where everywhere, then forces would cancel out and that's why you don't get a black hole.

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

#207

Post by deanCommie »

SkyMarshal wrote: post #30
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.

> 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…

So mindboggling that frankly I refuse to accept it.

The likelyhood that we'll figure this out in my lifetime is zero, but I simply can't comprehend a universe that accelerates without cause (dark energy) infinitely.

Just as we don't understand the root causes of dark energy, I believe it's just as logical to believe that something will eventually slow it down.

I have to believe that because only a cyclical theory of the universe makes sense to me. It's my faith, I suppose.

The more depressing part to me isn't that I'll never know, but rather it's entirely possible HUMANITY can never know, any more than an ant can know about General Relativity.

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

#208

Post by dark-star »

TheOtherHobbes wrote: post #151

I'm going to be very amused if the Steady State Model - an unpopular relic from the 1940s - turns out to be correct. https://en.wikipedia.org/wiki/Steady-state_model

My favorite theory is that the universe is finite, some sort of (hyper)sphere or -torus. If we could just look far enough out there we would see our own galaxy

What would be even cooler is if it was warped like a moebius strip in a higher dimension, so that when we look out there, everything is mirrored from "our" reality :-D

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

#209

Post by drdeca »

SketchySeaBeast wrote: post #162
freedude wrote: post #134

Earlier quoted context omitted.

ok, but what caused the big bangs? ... Genesis 1:1

You've just moved the "what caused the..." question up another level and then pleaded that your new level is somehow more special than the previous level without any actual justification. It's turtles all the way down and gods all the way up.

So what you do is you form a ordinal-indexed hierarchy of “why”s, And then you go up a universe level so that the class of ordinals in the lower universe level becomes an actual set and not just a class, and then you somehow (exactly how... remains to be seen) appeal to Zorn’s lemma , and construct a why-of-all-whys that explains everything in the lower universe level.

And you call that thing [ERROR: NOT REPRESENTABLE].

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

#210

Post by zmgsabst »

atemerev wrote: post #82

Something is wrong with the cosmic distance ladder. Space is anisotropic, or gravity interacts with itself somehow. The distances are not what they seem to be. I think this will eventually be the solution to the galaxy rotation / dark matter problem.

Our who claim that things are isotopic seems in conflict with what we see:

https://www.quantamagazine.org/asymmetry-detected-in-the-dis...

https://www.newscientist.com/article/2280743-enormous-strand...

Personally, I think this is strong evidence that primordial anyons were inflated — and we’ve failed to account for the energy these stored from inflation.

https://en.wikipedia.org/wiki/Anyon

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