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Analysis indicates that the universe’s expansion is not accelerating

ras.ac.uk

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Re: Analysis indicates that the universe’s expansion is not accelerating

#91

Post by omnicognate »

hn_acc1 wrote: post #24
Sharlin wrote: post #16

Earlier quoted context omitted.

Edit: A big brain fart, ignore the retracted part below. Colonizing the universe is of course impossible in 100My, barring FTL. What the paper I referred to [1] says is that colonizing the Milky Way may take less than that, and if you can do that, spreading to the rest of the observable universe is fairly easy, very relatively speaking. According to some calculations, it should in principle be possible to colonize th…

I found someone saying colonize the Milky Way Galaxy in ~90m years? Is that what you meant? The observable universe is ~93B LY - unless you're assuming FTL (and MUCH faster than light), I don't see how that's possible?

Time dilation means that you can get anywhere while experiencing an arbitrarily small amount of time. You can cross the galaxy in a second as far as special relativity is concerned. (With the expenditure of insanely vast amounts of energy, ofc.)

To an observer back home you'd look like you're travelling at merely extremely close to the speed of light, but to you the journey would take a second.

Re: Analysis indicates that the universe’s expansion is not accelerating

#92

Post by dylan604 »

ASalazarMX wrote: post #73
dylan604 wrote: post #58

Earlier quoted context omitted.

what? no. religion is not certain which is evidenced by the numerous sects of christianity with their own interpretations of the same book. while science might not have a definitive answer for everything, they distinguish from fact and theory.

> religion is not certain Ask any religious person if their religion teaches truth or lie, then ask them if that truth is the absolute truth. We'll wait.

just because you tell me water is not wet does not make it dry. also, the cool thing "about science is it doesn't need you to believe in it" or however the quote goes

Re: Analysis indicates that the universe’s expansion is not accelerating

#93

Post by pdonis »

Erem wrote: post #79
pdonis wrote: post #37

Earlier quoted context omitted.

> If true, then that means the big bounce is back on the menu I don't think so. Deceleration does not imply recollapse. AFAIK none of this changes the basic fact that there isn't enough matter in the universe to cause it to recollapse. The expansion will just decelerate forever, never quite stopping.

Wait but decelerating forever does in fact imply recollapse doesn't it?

No. The simplest example is a matter-dominated universe at exactly the critical density. It decelerates forever but never quite stops expanding--the expansion rate asymptotes to zero.

Re: Analysis indicates that the universe’s expansion is not accelerating

#94

Post by mindcrime »

cluckindan wrote: post #66
CamperBob2 wrote: post #47

Earlier quoted context omitted.

"Sorry, but as a large language model, I cannot provide advice on how to reverse entropy."

Thinking… Thinking… Thinking… The word ”entropy” can be reversed by writing its letters in reverse order. E-N-T-R-O-P-Y The first letter is E. The second letter is N. The third letter is T. The fourth letter is R. The fifth letter is O. The sixth letter is P. The seventh letter is Y. Thinking… To construct the reversed word, the seventh letter must be first, and the sixth letter must be second, and the fifth letter m…

yporrrtney

Looks like it halluco-commingled the physical principle and the drummer from Dream Theater...

Re: Analysis indicates that the universe’s expansion is not accelerating

#96

Post by pixl97 »

mrbluecoat wrote: post #45

I have a great deal of respect for the sciences but sometimes astronomy just feels like one giant guessing game: age of the universe, big bang starting as a joke and all the "first minute" timelines thereafter, dark energy and dark matter (code for we have no idea what it is) vastly outnumbering everything else, and now questioning the Nobel Prize-awarded universe expansion. Meanwhile, asteroids the size of buses+ ke…

I mean an asteroid the size of a bus is messy for your local area if it decides to land there, but in the terms of size of things in space is nearly undetectable. Space, even our local neighborhood is unbelievably huge.

Think of trying to find a bus that could be anywhere on earth that is moving so it's not easy to keep track of and is painted in a way to be camouflaged with its environment.

Now instead try to imagine looking for that bus on Jupiter. Gets way harder. But it's way bigger than that, your looking for a black dot in the size of an area of millions of Jupiter and just hope it crosses in front of a star so you can track it.

Most problems involving space are insanely hard.

Re: Analysis indicates that the universe’s expansion is not accelerating

#97

Post by patcon »

cluckindan wrote: post #66
CamperBob2 wrote: post #47

Earlier quoted context omitted.

"Sorry, but as a large language model, I cannot provide advice on how to reverse entropy."

Thinking… Thinking… Thinking… The word ”entropy” can be reversed by writing its letters in reverse order. E-N-T-R-O-P-Y The first letter is E. The second letter is N. The third letter is T. The fourth letter is R. The fifth letter is O. The sixth letter is P. The seventh letter is Y. Thinking… To construct the reversed word, the seventh letter must be first, and the sixth letter must be second, and the fifth letter m…

I love this. I've upvoted every parent just so you can get your dues :)

Re: Analysis indicates that the universe’s expansion is not accelerating

#98

Post by kloop »

dylan604 wrote: post #92
ASalazarMX wrote: post #73

Earlier quoted context omitted.

> religion is not certain Ask any religious person if their religion teaches truth or lie, then ask them if that truth is the absolute truth. We'll wait.

just because you tell me water is not wet does not make it dry. also, the cool thing "about science is it doesn't need you to believe in it" or however the quote goes

Sure, but they didn't say correctness, they said certainty

Re: Analysis indicates that the universe’s expansion is not accelerating

#99

Post by antonvs »

gcanyon wrote: post #87
antonvs wrote: post #40

Earlier quoted context omitted.

> After all, existence in itself is irrefutable and cannot not exist by definition. I can say the same about forgnoz, which is something I've just invented that must exist by definition. You'd need to try a bit harder to make existence actually inevitable.

I think they mean existence in general, not the existence of any specific thing. Meaning that if there were no “existence” then we wouldn’t be here to consider its nonexistence.

> I think they mean existence in general, not the existence of any specific thing.

Yes, but the definition of "existence" doesn't require that anything must actually exist.

In other words, it is not the case that existence "cannot not exist by definition."

> Meaning that if there were no “existence” then we wouldn’t be here to consider its nonexistence.

That's an anthropic principle argument, which is not an argument from the definition of existence. One of the premises of that argument is that we exist already.

Re: Analysis indicates that the universe’s expansion is not accelerating

#100

Post by Terr_ »

mrb wrote: post #90
sfink wrote: post #23

If you cover up the part of the Figure 3 graph past "now", it kind of fits a sine wave. https://ras.ac.uk/sites/default/files/2025-10/Figure%203.jpg Universe gong.

A funny coincidence is that the solar system was formed 4.6 billion years ago which is exactly when the universe's rate of expansion peaked according to figure 3. If you want to believe in an intelligent creator—not that I do—it's as if they were accelerating the expansion until the solar system was formed, then turned the control knob down.

Turns out the universe is one giant PID controller.
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