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.
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
#72Ethan Siegel isn't so certain: https://bigthink.com/starts-with-a-bang/most-distant-galaxie... The tl;dr is that we're finding quite a few red galaxies and red can mean distant (and therefore old) but you need to follow-up and do further direct measurements of each galaxy to be really certain that it's old and not red looking for some other reason. Some of these unexpectedly red galaxies have been followed up on, and…
They do talk about that a bit in the article:
"These candidates await spectroscopic confirmation: Their redshifts are only estimates for now. But so far, spectroscopic confirmations of other galaxies have confirmed the vast majority of preliminary distances. Even if only half of Yan’s selection turn out to be nearby galaxies masquerading as distant ones, the latter number would still be unexpectedly large."
Re: The James Webb Space Telescope is finding too many early galaxies
#73Does this mean that big bang either didn't happen or happened in a different way that we think of it? Or happened far earlier than we think it did? Complete layman here.
I think it's safe to say that it is still uncertain, but few (not zero) astronomers believe that it means the Big Bang didn't happen.
Re: The James Webb Space Telescope is finding too many early galaxies
#74Is it possible that the 'edge' of universe reflects light? Have scientists been able to conclusively rule that out somehow? Does the universe even have an edge? What is our current understanding of what the boundaries of the universe might be like?
I have a memory from when I was a kid and learning about the universe. In my head it definitely had an edge, and it resembled a really really big hockey rink with boards. But it was also only 2d at that time, which I think I remember knowing that wasn't right but not being able to conceptualize a 3d universe. So yes, in the universe of my 8yo mind the "edge" might reflect light
Re: The James Webb Space Telescope is finding too many early galaxies
#75Earlier quoted context omitted.
Am I understanding that paper correctly that their suggested solution to explain the Bullet Cluster using MOND is too introduce an additional kind of matter which can not be detected on earth and doesn't interact with light (namely sterile neutrinos)? Is this satire?
"dark matter but not as much" is still an improvement if you replace it with something better. If MOND predicted these observations and LCDM didn't it's reasonable to say that it is better.
Yeah that's fair. I guess it could also explain why DM has been so hard to pin down, if both MOND and DM are true then there might be DM candidates that have been unfairly ruled out.
I do think it significantly hurts the (more philosophical) argument that MOND is simpler or has fewer parameters than DM though.
Re: The James Webb Space Telescope is finding too many early galaxies
#76Earlier quoted context omitted.
What do I have to study to understand all this in mathematical terms? Is an undergrad text good enough?
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 universe is really a mind-bogglingly massive black hole that was sucked out of the actual universe, and the actual age of "the" universe is incalculably old, trillions of quadrillions of years old, and it's only our baby universe is what is roughly 13.7Byo? Maybe the Great Attractor hides the mother of all singularities. I'm sure there could be a way to explain the CBR and what seems like the Big Bang and Inflation. Maybe this baby universe only appears to be expanding, when it's just a growing black hole.
Re: The James Webb Space Telescope is finding too many early galaxies
#77Can someone explain to me what would be behind the galaxies if we could see it, to the point of 0 seconds after the big bang? Black, white, is it even possible?
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? :-)
Re: The James Webb Space Telescope is finding too many early galaxies
#78I 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 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" in a more economical way.
Could we train a GPT3 like model with the entire corpus of astronomical research and try to answer some questions that way?
Re: The James Webb Space Telescope is finding too many early galaxies
#79RIP Big Bang Theory
I have no idea if it is the end of the Big Bang Theory, but I think it would be super fun if it is:
* It doesn't have a negative effect on anything if it turns out to be wrong (other than some theses).
* It would be pretty cool to get a sense for how fallible we are
So I'm rooting against Big Bang Theory just for the experience of it :)
Re: The James Webb Space Telescope is finding too many early galaxies
#80Earlier 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…
Yes, true -- the distance between two points doesn't grow linearly, but rather proportionally to itself :D