it's not going to expand faster than what you're able to observe
Webb and Hubble confirm Universe's expansion rate
131–140 of 380 posts
Re: Webb and Hubble confirm Universe's expansion rate
#132I've asked this question before, but I don't think I received a good answer, so figured I'd try asking again. How do we know that galaxies are accelerating away from us and not moving at constant speed? People often point to the observation that the further away a galaxy is, the faster it appears to be moving away from us, implying acceleration. However, wouldn't we expect to see the same observation even without any…
How do we know that galaxies are accelerating away from us and not moving at constant speed? There's a more basic question: How do we know the galaxies are moving? It seems (I haven't seen any other response, like... ever) that we have one and only one way to measure the speed of galaxies: the red shift. It's impossible to triangulate those huge distances and the time scale would also be a barrier, so no way of confi…
“Degrading” sounds very intuitive to me. Can the frequency of the light waves simply slow down over a very long distance/time? Or maybe the speed of light simply slows down over an unimaginably long distance? We don’t have any model to describe such behavior, but everyday objects around us all slow down one way or another, what makes light so different?
Re: Webb and Hubble confirm Universe's expansion rate
#133Earlier quoted context omitted.
You would have to come up with an explanation for such drifting to be occurring across the entire visible universe in precisely the same way, across billions and billions of light years.
Just a fringe speculation without any physical basis: maybe the Big Bang emits a 4-dimensional spherical shell of matter at c ? With the direction in which we are traveling at c called “time”, and the other three which we're not moving through called “space”; diverging rays having spatial velocity relative to each other equal to tan(alpha) i.e. flat projection; and at any given point on the 4-sphere's 3D surface ever…
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Re: Webb and Hubble confirm Universe's expansion rate
#134This URL is a stub, and the full article can be read at https://www.esa.int/Science_Exploration/Space_Science/Webb/W...
Thanks! We've changed to that from https://www.esa.int/ESA_Multimedia/Images/2024/03/Webb_Hubbl... above.
Re: Webb and Hubble confirm Universe's expansion rate
#135Re: Webb and Hubble confirm Universe's expansion rate
#136If we can travel faster than light does it blow up the theory that the universe expands? Because if we can travel faster than light the universe is theoretically be infinite if I can go to a point pas the furthest reaches of stars/matter.
If we can travel faster than light, that would blow up all the theories that say that we cannot. And FTL travel would imply time travel (if in your reference frame, something is traveling faster than light, there's another reference frame where it is going backwards in time). A lot of science fiction just sweeps this under the table and pretends that we have Newtonian absolute time to go along with the FTL travel.
If we can do FTL it may just prove that light speed can be achieved by brute force, or an alternative method. No laws needs to be broken and new laws can be found. Like quantum physics and classical physics.
Re: Webb and Hubble confirm Universe's expansion rate
#137Can someone help me understand - point me toward some reading or ELI5 - what is the universe expanding into? (Or probably, why is that question not formulated well?)
One of the quantities described by Einstein's equations of General Relativity is the metric tensor—a matrix of matrices—that describes how "far" things are in space and time given the stuff in the local environment. One of the things that the equation tells us is that objects that are not gravitationally bound will tend to get farther away from each other as time passes. We call this the expansion of space. As far as we can tell, there isn't anything "outside" the universe is expanding "into"; distances just become larger somehow.
Re: Webb and Hubble confirm Universe's expansion rate
#138Earlier quoted context omitted.
Just a fringe speculation without any physical basis: maybe the Big Bang emits a 4-dimensional spherical shell of matter at c ? With the direction in which we are traveling at c called “time”, and the other three which we're not moving through called “space”; diverging rays having spatial velocity relative to each other equal to tan(alpha) i.e. flat projection; and at any given point on the 4-sphere's 3D surface ever…
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Re: Webb and Hubble confirm Universe's expansion rate
#139Earlier quoted context omitted.
Or it's a simulation and someone keeps pushing changes to production.
All the expert software engineers agree this is the most likely explanation. Have physicists looked into this?
> All the expert software engineers agree this is the most likely explanation.
That's quite a strong claim. I'm skeptical. Sources?
> Have physicists looked into this?
They shelved it right next to "God Made The Universe" in the "Unfalsifiable Propositions" section, under the title "Grad Students Made The Universe."
Re: Webb and Hubble confirm Universe's expansion rate
#140This article is titled "Webb and Hubble confirm Universe's expansion rate", however I don't see the expansion rate actually listed there, or in the comments. I see a mention of age, but not the rate. Does anyone know the rate? I clicked through to the paper itself[1], but wasn't able to interpret it from the details I could see
[1]: https://iopscience.iop.org/article/10.3847/2041-8213/ad1ddd