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Analysis indicates that the universe’s expansion is not accelerating

ras.ac.uk

201–210 of 218 posts

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

#201
post #159

Earlier quoted context omitted.

Yes but then there is always something that must exist which is the concept of absence of existence. So it doesn't make sense.

That's a requirement that you're imposing. If nothing exists, no concept of absence of existence exists. Concepts are for humans.

How can nothingness exists, if it is supposed to not exist since it is nothingness?

Concept are not really for humans, but humans can grasp them. Or would you say that the sun only exists because (some) humans see it?

It's not because a human is unaware of something that it does not exist. Its concept is still there somewhere. Independent of its treatment by human cognition.

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

#202
post #10

Was there a date at the top of this? I didn't see one. I saw a similar headlines earlier this year and I'm trying to understand that this is something new

You're probably thinking of the DESI BAO results from March, which also cast doubt on the standard cosmological model. These new results point further in the same direction as the DESI ones

https://newscenter.lbl.gov/2025/03/19/new-desi-results-stren...

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

#203
post #198

Earlier quoted context omitted.

Did he yell "They LAUGHED at me at Heidelberg! They said I was mad. MAD!" ? It is a very fundamental shift, though. The whole "Dark Energy/Matter" hypothesis has always seemed to me, to be a bit of a "Here, there be dragonnes" kind of thing, but I am nowhere near the level of these folks, so I have always assumed they know a lot that I don't.

I've never really gotten this criticism. Science has worked on "here be dragons" ever since it became a "thing". Neutrinos took like 40 years to discover after experiments earlier showed that either all of modern particle physics was wrong, or there was something that we couldn't see.

It wasn't a criticism. At least, not from me. It was just an observation.

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

#204

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…

> now questioning the Nobel Prize-awarded universe expansion

It is not questioning that the universe is expanding. It is questioning how the expansion is happening. Massive difference. The rate of expansion has always been more of a "probably" and "looks like" rather than "we have very strong evidence" (unlike expansion itself, for which there is very strong evidence). This is a classic "we have tweaked our model as we've learned more" type thing (assuming it holds).

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

#205
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.

All glory to forgnoz, a thing which I assure you does exist!

xD Fortunately we have forgnoz. All praise forgnoz. :D :D :D

What is it again?

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

#206
post #152
post #103

Earlier quoted context omitted.

Because energy cannot be created nor destroyed

Evidently energy was created, or it would not exist, would it ? It probably can be destroyed back to the pre-energy state in some way, just not on a scale we comprehend or even care about. I suppose we're like bubbles on a boiling pot of water when the fire stops: all this agitation spreads out on the entire volume, and sure no energy was lost, but there are so little bubbles and so much water, once the heat has spre…

>Evidently energy was created, or it would not exist, would it ?

It is constantly transforming, but that does not signify that it was created, that is beyond the evidence

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

#207
post #199

Earlier quoted context omitted.

There are two main claims that I think you may be touching on: 1. The question of whether concepts exist in the absence of a human mind to imagine them. This is still debated in philosophy. I'm not an expert, so I won't make a claim about this, but I will point out that if it was easy to resolve, it probably wouldn't be a field of active debate after 2000+ years. 2. The question of whether it is necessary that _somet…

I thought the smiley would make the 'Nope' less argumentative. Sorry if you felt it was offensive. This was in response to: > Side-note: the deontological argument is an argument for the existence of God, which uses the same principle as the grandparent which was not actually true. This is not the same principle. Maybe the way I expressed the idea wasn't too clear. A close principle, would be Descartes' cogito perhap…

No worries, i did feel it was a bit dismissive, but no hard feelings at all.

I think your main claim is that concepts exist even if there is not a human to perceive/think of them. I have no horse in that race, sorry if that’s disappointing haha.

However, sometimes your comments seem to be claiming that _something_ must exist. _This_ i disagree with. We can observe that something does indeed exist in our universe. However, there is nothing that forced that to be the case. It just happens to be.

Regarding English, your phrase choice is just a bit odd and somewhat poetic, haha. It reminds me a bit of my dad, whose first language was Farsi. Here’s a couple concrete examples from your writing:

- “Maybe the way I expressed the idea wasn’t too clear”. “Too” is close in meaning to “excessive” (among other uses). I think it would be more common to see “wasn’t so clear” or “wasn’t clear enough”

- “Besides, why human?” I think there are a few words that have been dropped here, which would not normally be dropped even in casual English. You mean something like “Besides, why do we need a human perspective?” From context your meaning is clear, but the phrase “why human?” just feels unusual. I think the phrase “why X?” is common when X is a verb, but not so much when X is a noun. Consider, “why drive?”, “why worry?”, “why wear that?” all sound normal to me. On the other hand “why apple?”, “why lamp?”, “why monkey?” all seem unusual, even somewhat humorous.

- “On a whole other note”: i think the common phrase here is “on another note”. I’ve never heard “whole other note” before.

And now I’m curious: Is English your second language? In either case, your writing is unique in a very interesting way, and not something you should be worried about. I like the style, it gives you much more personality than most comments i see.

Edit: I can’t help myself, I want to guess where you’re from, lol. My best guess is Central Europe. The use of “too” to be “adequate” feels vaguely French to me, although that’s probably just based on Hollywood portrayals, since I don’t know any French. So I’ll say French is your first language, but I’ll claim victory if it’s anything from Central Europe :P

Edit edit: after googling, i see France isn’t usually counted as Central Europe. But I’m leaving my guess as France + Central Europe

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

#208
post #51

Mainstream physics has been delighted to ignore/abandon essential conservation laws when talking about the expanding universe. It's kinda weird, I tried publishing a paper on it recently and it was not received well. In general, if conservation laws are to hold, expansion must be balanced with [eventual] contraction, is that not obvious? Apparently it was quite contentious to say until... this article?

Maybe this helps: https://www.preposterousuniverse.com/blog/2010/02/22/energy-... My favorite quote: > I like to think that, if I were not a professional cosmologist, I would still find it hard to believe that hundreds of cosmologists around the world have latched on to an idea that violates a bedrock principle of physics, simply because they “forgot” it. If the idea of dark energy were in conflict with some other mu…

You go into a cafe and order a slice of cake. One is delivered. You order three more, three more are delivered. You conclude that the kitchen has infinite cakes based on the observable evidence. That's the argument.

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

#209
post #167
post #32

> type Ia supernovae, long regarded as the universe’s "standard candles", are in fact strongly affected by the age of their progenitor stars. A key point in the article. From what I understand, this is the main way we measure things of vast distance and, from that, determine the universe's rate of expansion. If our understanding of these supernovae is wrong, as this paper claims, that would be a massive scientific br…

This is mostly my physics ignorance talking, but if we measure distance in space-time and not just space, and speed or velocity is space-time/time (which somehow are both relative to each other) and the derivative of velocity is acceleration, cant acceleration mean either expanding "faster" in the sense of distance OR time speeding up or slowing down? All of it seems so self referential its hard to wrap around.

Yes, it is the same thing, but since the objects are in free fall and there is no traditional force to cause the acceleration the better view point is that this is accelerated expansion of the universe. In a flat spacetime a forward light-cone can be identified with an expanding (no acceleration) universe where objects just fly away from a single point with constant but different speeds, i.e. an explosion. But in this model space as slice with the same local time after explosion is not flat. Also data seems to indicate that space is flat while space-time is curved on a large scale, so this picture is too simple.

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

#210
post #28

Seems like the problem should be pretty easy to figure out. Just need to wait ~5 gigayears and see which model is right. I'm personally hoping for deceleration so that we have more total visitable volume. I'll set a reminder to check back at that time to see who was right.

Oh, I'm not going to care about visitable volume. With 5 gigayears to work with I'm going to move a few star systems over, break down all the matter orbiting the star into a Dyson sphere made of computronium, and simulate visiting any world I could possibly ever want to.

This is one reason to assume we'll never meet any aliens. They're just simulating whatever all day long in their Dyson Goonspheres.
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