this post was submitted on 17 Mar 2024
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[–] [email protected] 77 points 8 months ago* (last edited 8 months ago) (2 children)

This model combines two ideasβ€”about how the forces of nature decrease over cosmic time and about light losing energy when it travels a long distance. It's been tested and has been shown to match up with several observations, such as about how galaxies are spread out and how light from the early universe has evolved.

These hypotheses never seem to stand up to rigorous analysis. Still, always welcome the discussion.

[–] [email protected] 24 points 8 months ago (7 children)

Absolutely. On the one hand, having ~26% of the known universe consisting of a substance that we cannot detect directly leaves a lot of questions open. On the other hand; dark matter is postulated because otherwise things like galaxy rotation curves don't match what we believe they should be from general relativity, and this theory doesn't seem to address that.

https://en.wikipedia.org/wiki/Bullet_Cluster#Significance_to_dark_matter

Also, light 'losing energy' would be a violation of the first law of thermodynamics, unless it loses it 'to' somewhere.

[–] [email protected] 7 points 8 months ago (2 children)

Light does actually just lose energy to nowhere in our current understanding of expanding space.

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[–] [email protected] 22 points 8 months ago

This is the same researcher that said the universe is 26.7 billion years old based on the JWST data instead of 13.8.

Happy to see ideas thrown out there to help us understand what dark matter is, but I'm really looking forward to all the random videos that eventually come out explaining why it holds up against a whole bunch of observational evidence while it ignores all the other observational evidence it doesn't hold up against.

[–] [email protected] 59 points 8 months ago (1 children)

It's time for people to start taking this matter lightly.

[–] [email protected] 7 points 8 months ago

Well played.

[–] [email protected] 49 points 8 months ago (1 children)

"In standard cosmology, the accelerated expansion of the universe is said to be caused by dark energy but is in fact due to the weakening forces of nature as it expands, not due to dark energy."

Fascinating! I'm looking forward to seeing where this goes. The "tired light" theory they mention doesn't seem to have held up to scrutiny, but maybe there's something else about weakening over time or distance that we haven't observed yet.

[–] [email protected] 3 points 8 months ago (2 children)

How would the gravitational forces weakening accelerate the expansion speed? It would at best "not slow it down", you can't explain the speed increase with this logic. That just sounds wrong. Am I missing something?

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[–] [email protected] 36 points 8 months ago (3 children)
[–] [email protected] 20 points 8 months ago (1 children)

where were u wen dark matter die

[–] [email protected] 30 points 8 months ago (1 children)

i was sat at home eating milky way when saturn ring

"dark matter is kill"

"no"

[–] [email protected] 15 points 8 months ago (1 children)

when saturn ring

πŸ₯‡

[–] [email protected] 8 points 8 months ago

Glad someone appreciated that, lol

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[–] [email protected] 29 points 8 months ago (3 children)

Just going to assume this popular science article is about a theory with no support as usual.

[–] [email protected] 25 points 8 months ago* (last edited 8 months ago) (1 children)

um i browsed it for nearly two minutes and at the very top of the page there was clearly a chart. i didn't understand it but obviously we can conclude that it is based on scientific science

[–] [email protected] 7 points 8 months ago

I have also seen the picture and can confirm, that it is, in fact, a picture.

[–] [email protected] 16 points 8 months ago (1 children)

*hypothesis. A theory (in the scientific sense) has to be tested and therefore has at least some support!

[–] [email protected] 5 points 8 months ago
[–] [email protected] 8 points 8 months ago

Always has been.

[–] [email protected] 25 points 8 months ago (7 children)

Don't get too excited, this is a pretty fringe theory that doesn't really have experimental evidence. They were able to make some observations fit with their theory without dark matter yes, but not all of them. The tired light part in particular has a lot of contradictions with observation that they don't explain.

So interesting, but far from definitive.

[–] [email protected] 6 points 8 months ago (2 children)

Couldn't the same be said for the proof of dark matter?

They were able to make some observations fit with their theory with dark matter yes, but not all of them

[–] [email protected] 9 points 8 months ago

Couldn’t the same be said for the proof of dark matter?

No, dark matter is actually a great explanation for lots and lots of observations; the only problem with it is that we don't know anything about it other than that it is such a good explanation for these observations.

[–] [email protected] 9 points 8 months ago

Generally for a new theory to be accepted, it needs to explain everything that the old theory did plus something more

[–] [email protected] 3 points 8 months ago

I'm a workshop kind of guy that enjoys space documentaries. For my part, I see "dark matter" as a known hole in our current understanding of cosmology, and I bet when we figure out how it does actually work it'll lead to some really cool TV shows.

[–] [email protected] 3 points 8 months ago (1 children)

If light got tired, wouldn't everything get blurry the further away it were?

[–] [email protected] 7 points 8 months ago (1 children)

I'm nearsighted, so that happens anyways

[–] [email protected] 4 points 8 months ago

Me too but I always knew that it was my eyes not the maximum draw distance of the universe that was to blame.

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[–] [email protected] 22 points 8 months ago (1 children)

This stuff is way, way over my head. And probably most of humanity right now. In this moment I can feel some envy and admiration towards whoever is around to understand the great breakthroughs we may one day have on this matter.

[–] [email protected] 20 points 8 months ago* (last edited 8 months ago) (2 children)

Coles notes: scientists made calculations on the universe and it didn't make sense because the math says there should be more mass and energy than what they know exists. So they called the missing mass dark matter and the missing energy, dark energy.

Now some guy in Ottawa figured out better math that doesn't need the "dark" stuff to make the math make sense.

[–] [email protected] 9 points 8 months ago (1 children)

My understanding of dark energy is a little different. As I understand it, we figured gravity pulls things together, right? So everything should be kinda slowly falling back together from the big bang. It was theorized to end in a 'big crunch' where the universe collapses back and then explodes again in a cycle.

Only when they tried to measure how fast distant objects were moving relative to us, they found that things were still moving away from each other. More than that, the farther away things were, the faster they were moving. Meaning distant objects were accelerating.

Acceleration requires energy, but we don't know the mechanism behind this, or where the energy comes from. Hence, dark energy.

[–] [email protected] 2 points 8 months ago (2 children)

So, dark energy is responsible of the expansion of the universe?

[–] [email protected] 5 points 8 months ago (1 children)

kinda, dark energy is the unknown explanation for the expansion of the universe. Once we understand it enough to know what it is responsible for it'll no longer be dark.

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[–] [email protected] 2 points 8 months ago

Maybe, we don't know.

[–] [email protected] 5 points 8 months ago

Just to be clear, there are lots and lots of different observations that are all explained by dark matter; it's not just a single term in "the math". Furthermore, the hypothesis presented in this article is not "better math" because it does not do as good a job as dark matter in explaining all of these observations.

[–] [email protected] 19 points 8 months ago (3 children)

Only white matter is allowed in this universe.

[–] [email protected] 11 points 8 months ago

All Matter Lives.

[–] [email protected] 6 points 8 months ago

Black matter lives

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[–] [email protected] 12 points 8 months ago* (last edited 8 months ago) (1 children)

I went and read the research.

I'm not an expert and as such can't really analyze it fully. But what I took away is that it aimed to test a part of new theory by with a very narrow measurement, using early-universe density oscillations. They left dark matter out of the equation with the new model, and it was a smashing success if you're willing to overlook that it requires the universe to be a completely different age than it is.. In short, this is shenanigans.

edit: I'm fine being wrong if I am, I'd love to know more from informed readers. That's just what I took away https://iopscience.iop.org/article/10.3847/1538-4357/ad1bc6#apjad1bc6s3

edit2: It also presumes the "tired light theory" is true. Tired light is the flat earth of astrophysics/cosmology. Yeah, there are contrarian knuckleheads in every discipline.

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[–] [email protected] 3 points 8 months ago (2 children)

Is anyone really surprised? Really neat study though!

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[–] [email protected] 3 points 8 months ago

Dark mind over dark matter, amirite?

[–] [email protected] 2 points 8 months ago
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