this post was submitted on 08 Apr 2025
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...there are two different ways to measure this cosmic expansion rate, and they don’t agree. One method looks deep into the past by analyzing cosmic microwave background radiation, the faint afterglow of the Big Bang. The other studies Cepheid variable stars in nearby galaxies, whose brightness allows astronomers to map more recent expansion.

You’d expect both methods to give the same answer. Instead, they disagree—by a lot. And this mismatch is what scientists call the Hubble tension...Webb’s data agrees with Hubble’s and completely rules out measurement error as the cause of the discrepancy. It’s now harder than ever to explain away the tension as a statistical fluke. This inconsistency suggests something big might be missing from our understanding of the universe - something beyond current theories involving dark matter, dark energy, or even gravity itself. When the same universe appears to expand at different rates depending on how and where you look, it raises the possibility that our entire cosmological model may need rethinking.

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[–] [email protected] 8 points 2 days ago (1 children)
[–] [email protected] 2 points 2 days ago* (last edited 2 days ago) (2 children)

Lerner is a massive kook and scam artist

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[–] [email protected] 7 points 2 days ago (1 children)

Most rational people will completely ignore this theory, but what if it's just God fucking with us?

[–] [email protected] 7 points 2 days ago* (last edited 2 days ago)

I could've sworn there was a thought experiment for an omnipotent being modifying the universe but only when we are intentionally trying to study it, but this is all I could find. https://en.wikipedia.org/wiki/Evil_demon

This concept is stuck in my mind as "Cartesian demon" but that only leads to the above which is more about the idea that we could be in a simulated reality. It's possible I'm getting an xkcd comic mixed in but I couldn't find it either based on a quick search.

Edit: The comic was something like a sliding scale (or maybe a flow chart) of different views of reality. On one end was everything is fake, even self, and the other end was that everything is real and measureable. Somewhere in the middle was the idea that reality exists but we can't measure it properly or objectively. Something like that. But it's also possible this comic was unrelated to whatever I'm remembering as "Cartesian demon" and I'm getting mixed up.

[–] [email protected] 93 points 4 days ago* (last edited 4 days ago) (14 children)

The article over-dramatizes the story. This "deeply wrong" discrepancy is less than 10%. CMB measurements predict a Hubble constant of around 68km/s/Mpc. Distance ladder measurements get around 73km/s/Mpc.

Our current understanding of the universe the Lambda-CDM model is still wildly successful and it's more likely that the true correct model of the universe will be a correction/extension to Lambda-CDM rather than a completely new theory (although if it is a completely new theory that would be pretty cool).

[–] [email protected] 36 points 3 days ago (1 children)

I think you're understating things. The measurements don't have to be 100 km/s/Mpc apart to cause problems for our understanding of the universe. Ruling out measurement error means we have to go back to the drawing board on cosmology. The problem isn't sloppy telescopes or anything -- it's definitely a hole in our current model.

[–] [email protected] 10 points 3 days ago

Yes it's a problem with the model. But it a problem that can very likely be fixed. We don't have to throw out the entire model and start from scratch.

[–] [email protected] 17 points 3 days ago

If they wanted to use the term "deeply wrong discrepancy", maybe they should have gone with the difference between the universe's expansion predicted by quantum vacuum energy and the actual, much slower observed rate of expansion.
By "much slower", I mean that the theory and the observations differ by something like one hundred and twenty five (!!!) orders of magnitude.

[–] [email protected] 16 points 3 days ago (2 children)

I think the deeply wrong part of it is that the difference is now big enough for the error bars to stop overlapping

[–] [email protected] 4 points 3 days ago (1 children)

The instrumental error bars are no longer overlapping. But if we imagine all the modifications one could make to Lambda-CDM, then there is still a huge "theory" error bar that subsumes all these.

Basically I'm saying the model is wrong, yes, but it can very much be fixed.

[–] [email protected] 2 points 2 days ago (1 children)

But could you make these modifications without diverging from other observations? If it were as easy as you put it, why have scientists been talking about it for decades?

[–] [email protected] 1 points 2 days ago

Scientists have came up with countless ways to fix the Hubble tension. But all these modified theories so far are either

  • contrived
  • untestable with present day observational instruments
  • currently being tested
  • already tested and deemed incompatible with reality.
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[–] [email protected] 2 points 2 days ago

Maybe the light does a detour before it reaches the telescopes.

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[–] [email protected] 140 points 4 days ago (3 children)

JWST doing exactly what it was supposed to do ! That's both exciting and terrifying !

[–] [email protected] 9 points 3 days ago (1 children)

What’s terrifying about learning more about his the universe works?

That’s just how all of science works.

It’s not kind JWST detected a black hole barreling towards us or anything.

[–] [email protected] 3 points 2 days ago
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[–] [email protected] 4 points 2 days ago

Off topic: no full screen popover showing up to ask me to subscribe/disable adblocker/accept cookies? What is this site and how do I give them money?

[–] [email protected] 15 points 3 days ago

It's the damn Sophons isn't it?

[–] [email protected] 7 points 3 days ago (1 children)

Maybe it's the observer and the universe is in superposition, unfolding in every moment. Playing a little game with us as we try to win by understanding it.

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[–] [email protected] 22 points 3 days ago

This website is slop even if it overlaps with reality at times.

[–] [email protected] 36 points 4 days ago (4 children)

I fully expect scientists of the 25th century to roll our current level of knowledge of the universe in one with flat earth and geocentrism.

[–] [email protected] 8 points 3 days ago* (last edited 2 days ago) (2 children)

If you're interested in this stuff, Thomas Kuhn's The Structure of Scientific Revolutions describes a lot of how science actually happens, where most normal science builds up accumulated information under an accepted paradigm, but occasionally those old models slowly become untenable with repeated observations that are anomalous or not explained by that existing accepted scientific paradigm. Then a scientific revolution occurs, the old paradigm is cast aside or limited in its scope, while the new paradigm takes over as the generally accepted set of theories. The book is one of the most cited works of the post-war era.

~~Geocentrism~~ Heliocentrism didn't have a clear advantage over ~~Heliocentrism~~ geocentrism, until Kepler made the observation that the planetary orbits were elliptical. (One big objection to geocentrism was that the stars should have some kind of observable parallax if the earth were moving around the sun, but that ended up being explained by learning just how freaking far away the stars are.) Heliocentrism with elliptical orbits, though, laid the groundwork for Newton's theory of gravitation.

Later on, Mercury's anomalous orbit just couldn't be made to fit Newton's theory, but astronomers held onto Newton's theories for decades before Einstein's general relativity was enough to explain it. Einstein's own cosmological theories needed to be fit in with the discovery of the cosmic background radiation and our expanding universe, and eventually we got to our current paradigm of the lambda-CDM model, which postulates the existence of dark matter to account for galactic structures, dark energy to account for the acceleration of the expansion of the universe. All along the way, there were discarded theories that just don't hold up.

The history of how we got here can help inform how we should speculate about where we might go next. New normal science might try to figure out what dark matter actually is (different theories can be tested by looking for different observations), without actually challenging the overarching lambda-CDM model. Or research into the Hubble Tension might allow enough observation to propose a new model entirely, for a revolution into a new paradigm.

And of course, Kuhn wrote his hugely influential book in 1962, so many decades of thought have refined and challenged some of those ideas. It's interesting stuff.

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[–] [email protected] 16 points 4 days ago (2 children)

But how could light pass through nothing? Surely there must exist a lumeniferous aether!

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[–] [email protected] 11 points 4 days ago

I mean, the recent discoveries actually do not dispute most of the previous theories. Most of the time the old theories are fringe cases where some parameters are simplified so you get the new theory that is actually a general case of the classical one. It's not like our old formulas stop working when we discover new cases...

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[–] [email protected] 28 points 4 days ago* (last edited 4 days ago) (1 children)

To be fair, there's always been something deeply wrong with how most people understand the universe.

[–] [email protected] 15 points 4 days ago (1 children)

To be fair, there’s always been something deeply wrong with how most people understand ~~the universe~~.

FTFY

[–] [email protected] 30 points 3 days ago (6 children)

To be fair, there’s always been something deeply wrong with ~~how~~ most people ~~understand the universe~~.

FTFTFY :P

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[–] [email protected] 17 points 4 days ago

James Webb confirmation confirms something is deeply wrong with how we write headlines.

[–] [email protected] 16 points 4 days ago* (last edited 4 days ago) (4 children)

Am I missing something or is there just no source given in this article? I would really like to be able to read more but I can’t find anything in the recent press releases from the JWST team or through a quick search. It doesn’t even say who the “researchers” are.

Also why is every other sentence bolded? It made it really hard to read.

Edit: It seems that the article is mostly taken from this 2023 NASA blog post. The raisin bread analogy is on Wikipedia.

Even if this isn’t AI slop this is a lazy article.

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[–] [email protected] 16 points 4 days ago (1 children)

This is really exciting stuff, tbh. It's kinda amazing that in a world where the frontiers have been settled, most fields have had a century to a thousand years of refinement, there are still areas of science where we have giant gaps in our knowledge, like scientists first discovering gravity, or the circumference of Earth.

Someone, perhaps someone who is already alive, is going to discover new math or observations that fundamentally change how we see the universe, with far reaching implications on cosmic exploration, travel the birth and death of our universe, and (I'm sure) many commercial applications.

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[–] [email protected] 18 points 4 days ago* (last edited 4 days ago) (1 children)

We don't even understand what caused the incomprehensibly fast rate of expansion after the Big Bang known as "cosmic inflation", but basically JWST has confirmed that the rate of acceleration of the universe is, itself, accelerating beyond our models. Everything, everywhere since 0.01 quectoseconds^1^ after the Big Bang has always moved faster than we could predict, and we don't why!

“What the results still do not explain is why the universe appears to be expanding so fast! We can predict the expansion rate of the universe by observing its baby picture, the cosmic microwave background, and then employing our best model of how it grows up over time to tell us how fast the universe should be expanding today. The fact that the present measure of the expansion rate significantly exceeds the prediction is a now decade-long problem called “The Hubble Tension.”

  1. Quecto, the smallest metric SI prefix, 1*10^-30^, is still 100x too large to measure the time between the Big Bang and Cosmic Inflation.
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[–] [email protected] 19 points 4 days ago (21 children)

Cool.

Also, what do folks use to block ads on mobile. I've been using FF with Ublock Origin, but lately it hasn't been cutting it.

[–] [email protected] 20 points 4 days ago (1 children)
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[–] [email protected] 19 points 4 days ago

Check which blocking lists you have. I use the same and don't see any ads

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