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The James Webb Space Telescope is finding too many early galaxies

skyandtelescope.org

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

#131

Post by sfifs »

shagie wrote: post #68
Twisol wrote: post #45

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. From my understanding, it's not that we're moving away from parts of the universe, but that the distance between us is growing so fast that light sent from one part will find that after traveling toward us for some amount of time, the remaining distan…

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)

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

#132

Post by mmusson »

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…

It may be more a question of a new generation of physicists, willing to consider that particle dark matter is not the explanation for the acceleration discrepancy.

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

#133

Post by luxuryballs »

I always wonder if light traveled billions of years to get here wouldn’t it be possible that it got distorted along the way? What if all these galaxies are just a sort of a typical pattern of what light looks like after an unfathomably long journey through space/gravity/time/etc? It could be likely that what we’re seeing is no indication of what was ever actually out there.

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

#134

Post by freedude »

robg wrote: post #121

Instead of one big bang, imagine an infinite number of big bangs, all colliding on a cosmic scale in time and space. That’s not necessarily a multiverse, but it is a megaverse with universe as the old paradigm.

ok, but what caused the big bangs?

...

Genesis 1:1

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

#135

Post by fnovd »

Maursault wrote: post #76
hnuser123456 wrote: post #57

Earlier quoted context omitted.

The universe is 13.7b yo, but due to acceleration of expansion, if you could "teleport", it's actually currently 93b ly across. So we're already in a bubble within a greater universe that we'll never be able to escape even if you could instantly reach lightspeed right now, and due to the expansion continuing to increase, the fractional size of this bubble relative to the rest is shrinking. Faraway galaxies that are "…

> The universe is 13.7b yo, but due to acceleration of expansion, if you could "teleport", it's actually currently 93b ly across. So we're already in a bubble within a greater universe that we'll never be able to escape This number, the age of the universe, has changed a few times since I learned to read 45 some years ago. What are the chances that this isn't really "the" universe, but what we know as the observable…

It's black holes all the way down. Fun to note that, from the reference of someone outside a black hole, the singularity contained within hasn't happened yet, and never will.

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

#136

Post by tim-fan »

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…

Relevant xkcd: https://m.xkcd.com/2682/

And from the alt-text:

"Friction-driven static electrification is familiar and fundamental in daily life, industry, and technology, but its basics have long been unknown and have continually perplexed scientists from ancient Greece to the high-tech era. [...] To date, no single theory can satisfactorily explain this mysterious but fundamental phenomenon." --Eui-Cheol Shin et. al. (2022)

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

#137

Post by Waterluvian »

bcaulfield wrote: post #71

Great news. Finding stuff that doesn't fit into the current model and we need smart people to get to work understanding may be the surest sign that the JWST is invaluable.

This reminds me of how when you’re right, you don’t learn much. When you get it wrong, you learn a ton.

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

#138

Post by bruce343434 »

freedude wrote: post #134
robg wrote: post #121

Instead of one big bang, imagine an infinite number of big bangs, all colliding on a cosmic scale in time and space. That’s not necessarily a multiverse, but it is a megaverse with universe as the old paradigm.

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

ok, but what caused Genesis 1:1?

...

big bang

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

#140

Post by Eduard »

beambot wrote: post #125
Eduard wrote: post #113

Earlier quoted context omitted.

> there isn't even an accepted explanation for why rubbing a balloon on your head makes it stick to a wall But the accepted explanation is "static electricity", no? Or do you mean we don't "really" know when asking a couple of follow-up "why?" questions further?

This is the triboelectric effect, and the low-lying mechanisms are poorly understood & poorly characterized.

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.
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