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Some Astronomers Will Re-Examine a 102-Year-Old Theory About the Universe's Expansion (futurism.com) 77

Several "high-profile astronomers" will meet at London's Royal Society (the UK's national academy of sciences), "to question some of the most fundamental aspects of our understanding of the universe.reports Futurism: As The Guardian reports, the luminaries of cosmology will be re-examining some basic assumptions about the universe — right down to the over-a-century-old theory that it's expanding at a constant rate. "We are, in cosmology, using a model that was first formulated in 1922," coorganizer and Oxford cosmologist Subir Sarkar told the newspaper, in an apparent reference to the year Russian astronomer Alexander Friedmann outlined the possibility of cosmic expansion based on Einstein's general theory of relativity. "We have great data, but the theoretical basis is past its sell-by date," he added. "More and more people are saying the same thing and these are respected astronomers."

A number of researchers have found evidence that the universe may be expanding more quickly in some areas compared to others, raising the tantalizing possibility that megastructures could be influencing the universe's growth in significant ways. Sarkar and his colleagues, for instance, are suggesting that the universe is "lopsided" after studying over a million quasars, which are the active nuclei of galaxies where gas and dust are being gobbled up by a supermassive black hole.

The article notes that another theory is that the so-called cosmological constant that's been used for decades "actually varies across space."

Thanks to long-time Slashdot reader schwit1 for sharing the article.
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Some Astronomers Will Re-Examine a 102-Year-Old Theory About the Universe's Expansion

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  • Wouldn't it be nice to be living in a universe that doesn't require a big bang or heat death?
    • Why? While a one-shot or cyclical universe can make you feel like on long time scales life is meaningless... one in eternal dynamic equilibrium has the same philosophical result only with slightly different details.

  • So? (Score:4, Funny)

    by Anonymous Coward on Sunday April 21, 2024 @03:10AM (#64411652)

    right down to the over-a-century-old theory that it's expanding at a constant rate. "We are, in cosmology, using a model that was first formulated in 1922,"

    That's not that bad. Pythagoras' theorem is like two and a half thousand years old. We should replace that first.

    • right down to the over-a-century-old theory that it's expanding at a constant rate. "We are, in cosmology, using a model that was first formulated in 1922,"

      That's not that bad. Pythagoras' theorem is like two and a half thousand years old. We should replace that first.

      Anti-science skepticism isn't amusing anymore. Even in the fine summary it was made clear: in the time since forming the theory they've acquired dramatically improved observation abilities and there's significant evidence that the theory is at least partially incorrect. If there was similar for the Pythagorean Theorem then yeah, that too should be revisited. Otherwise bringing it up is unhelpful at best.

      • by ceoyoyo ( 59147 )

        You've dismissed an insightful comment.

        It's apparently not exactly clear what 1922 theory he's referring to, but we certainly didn't just take something from 1922 and use it today as is.

        There's general relativity, which we keep trying to poke holes in, the idea of the big bang itself, which dates to the 40s, dark matter, from ~1930s, refined and tested in a lot of different ways since then, dark energy from 1998, inflation in the 1970s, and a bunch of other things.

        If you want to point to a single theory und

      • ... there's significant evidence that the theory is at least partially incorrect.

        Too softball. That's not what the article said. "Significant," evidence is redundant. Evidence is sufficient on its own and scientists don't have that yet. That's the point of the effort. "At least partially incorrect," suffers as well. "Incorrect," does not need modifiers. Scientists have verified Hubble's Constant since it became a thing. While the precise value is difficult to pin down, the value still exists for now.

        It's like saying, "Relativity (special and general) needs to be re-examined." Of course

      • "Anti-science skepticism isn't amusing anymore."

        Whoopsie, did we jump the gun in our zealous attempts to be cool with the in-crowd by attacking anti-science wherever it may possibly be lurking, even if we paint with way too broad a brush as proved by this particular attack, eh?

        How "scientific" is it to use the emotion of ridicule and the feeling of being cool as your go-to weapon in your fervent hunt for anything that threatens the status quo?

        • "Anti-science skepticism isn't amusing anymore."

          Whoopsie, did we jump the gun in our zealous attempts to be cool with the in-crowd by attacking anti-science wherever it may possibly be lurking, even if we paint with way too broad a brush as proved by this particular attack, eh?

          How "scientific" is it to use the emotion of ridicule and the feeling of being cool as your go-to weapon in your fervent hunt for anything that threatens the status quo?

          Huh?

          No, genuinely what are you trying to convey here?

          • He's trying to play some "Say you don't have an argument without saying 'I don't have an argument' " game?
    • We already replaced Pythagorean's Theorem, for use in non-Euclidean geometry.

      https://en.wikipedia.org/wiki/... [wikipedia.org]

      • We already replaced Pythagorean's Theorem, for use in non-Euclidean geometry.

        https://en.wikipedia.org/wiki/... [wikipedia.org]

        That is stating the obvious. When you attempt to apply rules developed in one system (Euclidian geometry) to another system (Non-Euclidian geometry) it is reasonable to expect that some rules may not fit.

        Otherwise, if all the rules of one system fit the other system, then they would both be called the same name, right?

        • Keep in mind that at the time they didn't believe in irrational numbers, negative numbers, nor non-Euclidean geometry.

    • It's already known that the expansion seems to be accelerating. Several supernova studies all point to an accelerating expansion likely driven by Dark Energy but, regardless of the cause, we already know the expansion rate is not a constant.
    • right down to the over-a-century-old theory that it's expanding at a constant rate. "We are, in cosmology, using a model that was first formulated in 1922,"

      That's not that bad. Pythagoras' theorem is like two and a half thousand years old. We should replace that first.

      +1 Funny ... if I had Mod points

    • by necro81 ( 917438 )

      Pythagoras' theorem is like two and a half thousand years old.

      I was about to retort that Pythagoras doesn't hold in non-Euclidean space, which general relativity (and abundance evidence) indicates we live in.

      But then I do a little digging and learned, gosh-darnit, a form of the Pythagorean theorem still holds in hyperbolic and elliptical geometries [wikipedia.org].

      I guess that makes me one of today's lucky 10000?

  • I think it has been decades since cosmologists believed the universe is expanding at a constant rate.

    • by HiThere ( 15173 )

      Well, this summary is based on a story from someone quoting a story in The Guardian. Not the best way to get accurate news on science.

      • Yeah, I'm hunting around the RS's website looking for some information about this meeting ... to find it has gone down the cracks. Their programme of meetings covers 25th Apr onwards, while the Grauniad item talks about "this week's meeting" ... and if it's going at the moment, then the videos won't be on YT, yet. (The most recent RS video is "Dr Anthony Fauci on the lessons from AIDS and COVID-19 , 1.6K views, 4 days ago"). (Not a particularly engaging set of lectures. The RI is better.)

        The named organise

      • Found it via the 3rd name.

        https://royalsociety.org/scien... [royalsociety.org]

        15 - 16 April 2024 09:00 - 17:00 The Royal Society ... ah, the GRauniad article is from the 14th!

        Scientific discussion meeting organised by [names]

        Is the universe simple enough to be adequately described by the standard [lambda]CDM cosmological model which assumes the isotropic and homogeneous Friedmann-LemaiÌtre-Robertson-Walker metric? Tensions have emerged between the values of cosmological parameters estimated in different ways. Do thes

        • Bloody Slashcode can't even handle a perfectly reasonable HTML entity, "& chi ;" necessary to spell "ArXiv" correctly.
  • by getuid() ( 1305889 ) on Sunday April 21, 2024 @03:59AM (#64411698)

    ...it's aliens!

    I mean, just think about it! Where is everybody? The great filter and stuff...

    Why they're here, of course. There's a lot of them, and they're using some kind of space-bending interstellar travel (and possibly energy generating) technology. And once bent and stretched, space kind-of springs back to its original shape, but not quite all the way. There's am ever-so-slight distortion left.

    So universe expansion is the "smog" of interstellar travel, the "micro plastics" of ancient, still.thriving, alien civilizations. What we've found is just the high population density areas of the Universe.

    Us trying to figure out "the laws & constants of the universe" is like plankton tying to figure out "the laws and constants of the ocean" when they observe that heavy-metal contamination is accelerating, the gulf stream is subsiding, and generally, temperature is rising. Rapidly. I'm sure they'll come up with some "theory", but c'mon... we all know how realistic it'll be.

    There. Mistery solved. You're welcome.

    Don't forget to include me in the authors list when you make this groundbreaking publication in a cosmological journal!

  • This headline is a pretty good example of what? As if no astronomer prior to this reviews and questions theories? Well, probably not as we all know that there was nothing, then there was something, and then a big bang.
    • by Ol Olsoc ( 1175323 ) on Sunday April 21, 2024 @07:54AM (#64411832)

      This headline is a pretty good example of what? As if no astronomer prior to this reviews and questions theories? Well, probably not as we all know that there was nothing, then there was something, and then a big bang.

      And then the Big Cuddle, and the guy falls asleep

  • What if the universe is rotating like a wheel, planets orbit the sun, the stars orbit the galactic center, maybe scale that up to the whole universe and the only reason science hasn't discovered the rotating universe is because of it's immense size, were only seeing a very small piece of it
    • by Anonymous Coward

      You're very clever, young man, very clever -- but it's turtles all the way down!

    • The universe doesn't rotate because there is no reference frame for it to rotate in, if there were then the universe wouldn't be the universe.

      • Its just a hypothesis, I have no evidence, and you don't know it doesn't any more than I know it does, some things I think will forever remain a mystery forever because of human limitations
        • No, they know it doesn't, you may believe it does but you don't know it... because it doesn't.

          The term 'universe' means 'everything'. Everything can't rotate because there's nothing else for it to rotate relative to.

          Not only that, but if it was rotating, it would have an obvious centre and we would see everything orbiting it. Even if we were in a tiny little segment of visible universe in a far more vast rotating universe, there would be patterns evident in the movement of stars that we just don't see.

          • Everything can't rotate because there's nothing else for it to rotate relative to.

            Not only that, but if it was rotating, it would have an obvious centre and we would see everything orbiting it.

            I don't think so. Not necessarily.

            Consider a universe - the whole shebang, everything, no external reference frame. Separate it into two regions, of (approximately) equal size ; set one part rotating clockwise relative to the other, and the second part rotating anticlockwise relative to the first.

            You now have a un

      • by ceoyoyo ( 59147 )

        Rotation isn't relative the same way unaccelerated motion is. The net angular momentum of the observable universe has been measured repeatedly. As far as we can tell, it's zero.

      • by Geoffrey.landis ( 926948 ) on Sunday April 21, 2024 @01:19PM (#64412354) Homepage

        The universe doesn't rotate because there is no reference frame for it to rotate in, if there were then the universe wouldn't be the universe.

        In General Relativity, rotation is not relative. You can tell if you're rotating without reference to the outside universe, and in fact Gödel showed a solution to the Einstein field equations [aps.org] for the case of a rotating universe (...and the solution was pretty weird [space.com]).

        But, sufficiently precise astronomical measurements have looked for whether the universe is rotating, and it turns out it isn't.

    • What if the universe is rotating like a wheel

      Then we would know because while the universe refuses to define a common zero for velocity (velocity is relative), it absolutely does define a common zero acceleration.

  • by cascadingstylesheet ( 140919 ) on Sunday April 21, 2024 @07:03AM (#64411788) Journal

    Certain topics do not lend themselves very well to the scientific method [wikipedia.org].

    It's kind of hard to set up 100 universes, say, and run them through a few billion years. You can't do the experiment part.

    • Re: (Score:3, Insightful)

      by Black Parrot ( 19622 )

      Certain topics do not lend themselves very well to the scientific method.

      It's kind of hard to set up 100 universes, say, and run them through a few billion years. You can't do the experiment part.

      Sometimes a hypothesis has potentially observable implications, even if a mad scientist can't reproduce everything in their lab.

    • Certain topics do not lend themselves very well to the scientific method [wikipedia.org].

      Can you suggest a better method ? At least it is better than religion which works by making assertions and then continuing to hold them even when there is evidence to the contrary.

    • Sure you don't get a "control" in the traditional sense which is where models and simulations come in but more importantly astronomers can do the most important part which is predictions, if we can theorize something will happen based on observable evidence and then observe it happening like we predicted then that is still scientific method. It's actually far more flexible then we were taught in school.

      Of course things in cosmology and such don't carry the same weight of something you can experiment on wit

    • Shrug. We can't do experiments in historical geology (what happened in the past), but that doesn't render the field unscientific - it just means we have to use more indirect arguments and slightly longer chains of inference.
  • by burtosis ( 1124179 ) on Sunday April 21, 2024 @07:16AM (#64411794)
    First off no actual scientist thought it was even a constant for decades at least. It’s more like saying a car went from stopped at a light to some speed x a block later giving it an average acceleration of y. This is the Hubble expansion, simply a current measurement of the receding velocity of far off things in the universe whose rate are correlated to their distance in a rather linear relationship. In fact, most believe there was a period of inflation faster than light early on to account for how balanced and equal disparate sections of the universe are, despite no time for equilibrium to occur since the Big Bang.

    Currently, we can’t even agree on this average acceleration because measuring expansion by cosmic markers of stars like cephid variables and measuring it by the cosmic microwave background give conflicting results [nasa.gov]. This is called the hubble tension and underlines how we don’t have a handle on even gross measurements yet.

    In 1998 it was discovered the universe was actually accelerating in its expansion, the 2011 Nobel Prize in physics was awarded to Saul Perlmutter at the Lawrence Berkeley National Lab and Brian Schmidt at the Australian National Lab and Adam Reiss at Johns Hopkins University for their discovery. Until then everyone was hung up on the universe slowing down its expansion, falling back in on itself, expanding forever but never reaching a critical size, or continuing to expand forever but doing so more and more slowly. Turns out it was none of them at all.
    • by Baron_Yam ( 643147 ) on Sunday April 21, 2024 @09:09AM (#64411924)

      Unfortunately, while you are correct, you are arguing against a point that wasn't made.

      They suspect the expansion rate varies not only over time but across space as well.

      • Unfortunately, while you are correct, you are arguing against a point that wasn't made.

        They suspect the expansion rate varies not only over time but across space as well.

        “right down to the over-a-century-old theory that it's expanding at a constant rate.”

        I know reading the article is not really expected, but not reading the summary goes a bit far. If the journalists weren’t so terrible at writing these things they would have used “right down to the over-a-century-old theory that it's expanding symmetrically”.

        • It was in the second paragraph of the summary...

          • It was in the second paragraph of the summary...

            That does not undo what the earlier false statement professes. What’s not in the article is the guy is a crank who professes in the tired light hypothesis [youtube.com] (if you want details explained to you by an actual scientist) and it really came down to releasing results before proper calibration of jwst data. No serious scientist believes the universe is double the age since the Big Bang, this has been debunked in the previous 8 slashdot articles on the same subject just since 2020. Not to say the universe

      • Comment removed based on user account deletion
        • There's a difference between "space and time," referring to local events, and "spacetime," referring to the universe as described by special and general relativity.

      • you are arguing against a point that wasn't made.

        The point _was_ made: "constant rate" means that the rate of expansion remains the same with time. What you are talking about is a _common_ rate of expansion. The summary says that they are considering variations in the rate as a function of position but, by saying that the rate is constant that inplies that it does not vary with time and that is wrong: we know from multiple supernova studies that the expansion is accelerating. This even gave is a new possible "end of the universe" scenario: the "big rip"

    • > First off no actual scientist thought it was even a constant for decades at least.

      The working assumption was that it was constant because all the other known forces are constant. It had been "constant unless proven otherwise".

      It's premature to conclude such, but the lumpiness fits the "budding universe" theory whereby some portions of our universe will eventually collapse back on self and re-explode into a new universe in another dimension (string?) with slightly different "parameters". Universes may b

    • While you are correct, one thing we must tackle is the standard candle. We don't know with certainty just how far stuff is. Locally, we are pretty close to figuring out distance. Not surprisingly, as distance increases, our candles are extrapolations of a best guess. Until we fine-tune the candles I don't see us making much progress.

      • You haven't noticed any of the astronomical publications about refinements to the chain of "standard candles" across the observable universe over the last 40+ years? I remember reading about these things in the town library in the late 1970s, in the university library in the 1980s, the journals waiting, wedging the front door shut when I got home in the 1990s, and on ArXiv (it's a chi, not an "X", but Slashcode can't handle HTML) in the 2000s, 2010s and 2020s.

        The process of refining those candles continues

  • ... a new particle. To carry the property of mass across space. And bend space-time to produce the emergent field which we call gravity. One with a very long, but not infinite lifetime. So that its decay across space produces the non uniformity that we observe.

    Sorry, but the Higgs boson cannot be responsible for mass directly. It has too short a lifetime to even be directly observable in the LHC. Never mind moving across galaxies or the universe like photons do.

  • by kbahey ( 102895 ) on Sunday April 21, 2024 @11:10AM (#64412144) Homepage

    If the topic of this story is of interest to you, then watch Subir Sarkar's lecture on Beyond The Cosmological Standard Model [youtube.com].

    Sarkar is a professor at Oxford who has done some interesting work providing evidence that the expansion of the universe is NOT accelerating.

    Instead, he is saying that there is a dipole effect because earth, and the galaxy cluster that we are in, are all moving in space, and that gives the effect of accelerating expansion!

    He provides compelling evidence (for a non-specialist at least) for what he says and also casts doubts on the evidence for acceleration by analyzing their data (supernovae as standard candles, and their red shift), since a dipole effect is observed on that.

    If his hypothesis is confirmed by other research and observations, then the Nobel Prize for Saul Perlmutter and Adam Reiss maybe for nothing ...

    An area to watch for sure ...

    • by ceoyoyo ( 59147 )

      The problem with public lectures is that you have to simplify things, and that means skipping the details.

      You can present a compelling story about cosmology and the dipole in the CMB. Or the quadropole, which is weirder. Or that our galaxy is in a denser than average part of the universe. Or that our galactic cluster might be in a void.

      They all have different effects, in all directions, all depend on particular sets of assumptions which aren't unreasonable but also aren't guaranteed to be true, and all are

      • by kbahey ( 102895 )

        The lecture is based on published research done by him and his post doctoral student.

        Again, it is an area to keep an eye on, and nothing is definitive yet.

        • by ceoyoyo ( 59147 )

          Of course it is. I'm not saying he's wrong. I'm saying "compelling" is a trap. Humans love stories, and scientists these days are highly encouraged to tell stories. When I was in grad school they paid people to come and teach us how to tell compelling stories.

    • very interesting. so we may be interpreting angular velocity as expansion.
      • by kbahey ( 102895 )

        That is it in a nutshell ...
        And it makes a lot of sense, if the observations are correct.

        If his research pans out, then one Nobel Prize was awarded for an erroneous interpretation.

        Adam Reiss, Nobel Laureate for that prize criticizes Sarkar's work, but he has a vested interested in the status quo. Other experts should chime in, and more observations and analysis are needed.

        • I think his argument is compelling. I laughed out loud several times, esp when he says... xyz is off by a factor of 10 to the power of 60!! but then the additional info raises that to 10 to the power of 120!!!... then he says... makes no difference, the baseline was already off by a power of 10 to the 20, so "You're screwed anyways!" ... ha ha.. a good amount of self awareness.....

          so where does that leave us? Does that basically nullify the red shift?
          and if so what could we draw from that? Not necessarily t
          • by kbahey ( 102895 )

            so where does that leave us? Does that basically nullify the red shift?
            and if so what could we draw from that? Not necessarily that the universe is quite a steady state?

            No, the universe is still expanding.
            This has been established since Slipher/Hubble in the 1920s or so.

            But, if Sarkar is right, then this expansion is NOT accelerating, which was what the 2011 Nobel Prize [nobelprize.org] was awarded for.

            And it may resolve the "crisis in cosmology" where the rate of expansion is different when measured using two different phe

    • Thanks for digging that out. I didn't come across that in my hunting (I was working from the RS end more than this guy's website.

      Off to watch and write notes.

    • Oh, OU Phys.Soc.

      Didn't know they had one that videoed lectures etc - but not surprised. I stumbled onto the OU Archaeology Soc. recently, and they had an interesting few hours of presentations there, so I think the Phys.Soc should repay a good search too.

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