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Big Bang Breakthrough Team Back-Pedals On Major Result 127

Posted by samzenpus from the no-bang dept.
An anonymous reader writes A few months ago researchers announced they had discovered proof of the big bang. Now they're not so sure. Further research suggests cosmic dust might have skewed the results. "Back in March, the BICEP2 team reported a twisted pattern in the sky, which they attributed to primordial gravitational waves, wrinkles in the fabric of the universe that could have been produced when the baby universe went through an enormous growth spurt. If correct, this would confirm the theory of inflation, which says that the universe expanded exponentially in the first slivers of a second after the big bang – many believe that it continues to expand into an ever-growing multiverse. Doubts about the announcement soon emerged. The BICEP2 team identified the waves based on how they twisted, or polarised, the photons in the cosmic microwave background (CMB), the earliest light emitted in the universe around 380,000 years after the big bang. Other objects, such as the ashes of exploding stars or dust within our galaxy, can polarise light as well."
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Big Bang Breakthrough Team Back-Pedals On Major Result More

Big Bang Breakthrough Team Back-Pedals On Major Result

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  • Not the Big Bang (Score:5, Informative)

    by TrekkieGod ( 627867 ) on Sunday June 22, 2014 @09:38AM (#47292743) Homepage Journal

    There's a ton of evidence for the Big Bang, the existence of the CMB at all being one of them. That result was meant to be evidence for Inflation [wikipedia.org], which is used to explain why the universe appears evenly distributed everywhere you look, among other things.

    • Cosmic inflation has always puzzled me - so the distance between particles of matter is slowly widening, without the particles themselves actually moving, why can't we observe this at the molecular level? Or do we? Even if its only a miniscule expansion at the smallest scales it must surely show some sign, and wouldn't it have some effect on say chemical interactions?

      • Scientists call it the big rip. [wikipedia.org]

      • Re:Not the Big Bang (Score:5, Informative)

        by careysub ( 976506 ) on Sunday June 22, 2014 @11:12AM (#47293153)

        Cosmic inflation has always puzzled me - so the distance between particles of matter is slowly widening, without the particles themselves actually moving, why can't we observe this at the molecular level? Or do we? Even if its only a miniscule expansion at the smallest scales it must surely show some sign, and wouldn't it have some effect on say chemical interactions?

        There are three different expansive phenomenon in modern cosmology - the initial inflation of the original symmetry breaking event, the subsequent vastly longer and slower expansion (measured by the Hubble Constant) that followed where the Universe coasted under influence of gravity alone, and then the recently discovered (and cosmically more recent) cosmic acceleration.that is now offsetting gravity.

        The first event lasting a trillionth of a trillionth of a trillionth of a second did indeed push all the particles then existing apart very fast, while creating lots of new particles.

        The second phase of coasting, and the modern phase when cosmic acceleration kicked in, is currently pushing things apart on a cosmic scale, but not gravitationally bound structures, much less the far more strongly bound electromagnetically bound ones (atoms and molecules, and molecular agglomerations) or nuclear force bound structures.

        Eventually, under current models, cosmic acceleration will strengthen to the point where it will start ripping apart these galaxy clusters. then galaxies, then star systems, then stars and bulk matter, then molecules and atoms, then nuclei,and finally composite subatomic particles themselves.

      • Re: (Score:2)

        by AdamHaun ( 43173 )

        The Usenet Physics FAQ has a page covering this, although it doesn't answer your question directly:

        http://math.ucr.edu/home/baez/... [ucr.edu]

      • As I understand it, chemical reactions, electron orbital sizes, etc, will all be the same even after space has expanded many times. While space is still expanding slowly, it's not having much effect on anything - the other forces (not that expansion is really a force, though it has similar effects) acting between molecules in close proximity will be overwhelming.

        Again AIUI, an electron could continue happily in its orbit while space expands 10, 100 or 1000 times - as long as the expansion remains relatively

        • It's not the simple fact that space is expanding that might cause a big rip, but the fact that the expansion is accelerating, and will - one day - be so fast that it will outpace light, at which point no forces will be able to act over even a Planck distance (because by the time they've propogated, that Planck distance will have expanded too much).

          And what happens when that happens? I'm going to guess the result is universal and cataclysmic. We could even give it a name. Let's call it The Big Bang.

    • Comment removed based on user account deletion

      • Re:Not the Big Bang (Score:4, Informative)

        by mbone ( 558574 ) on Sunday June 22, 2014 @12:21PM (#47293459)

        The speed of light is the ultimate speed limit relative to the underlying spacetime. If spacetime itself expands or contracts, that speed limit may not apply. That is, in fact, also the basis of the Alcubierre warp drive [wikipedia.org].

        • How does spacetime know how fast something is going through it? If there is nothing else other than spacetime and a single photon, what regulates the photon's speed? What is the speed relative to?

          • Get ready for a shitty science analogy. Someone please chime in if this is just plain wrong.

            You are sat on a boat in a pool, with a motor capable of pushing it at 5m/s, and this is the only force applicable to the boat because physics. You cannot observe anything outside of the boat's speed in the water; There is only you, the boat, and the water. Now, put a current in the water of 50m/s in the direction of travel of the boat. How fast is the boat going? You can't know anything about the speed of the water

          • How does spacetime know how fast something is going through it? If there is nothing else other than spacetime and a single photon, what regulates the photon's speed? What is the speed relative to?

            The easiest way to answer that is by saying you're thinking about it incorrectly. Our every day experiences leads us to believe that distances are absolute. That time periods are absolute. And if we're talking about the relative speeds in human experience, that's a very, very good approximation.

            Turns out reality is weirder. It's not that spacetime "knows" how fast something is traveling through it. It's that space and time don't behave like our senses lead us to believe. So, from our perspective, if e

        • Doesn't the Alcubierre drive have the same causality issues as any other FTL form of propulsion?

      • Re: (Score:3)

        by Opyros ( 1153335 )
        The law of physics in question states that no information can be propagated faster than light. This does not conflict with space itself expanding superluminally. I'd suggest this Usenet FAQ, Is Faster-Than-Light Travel or Communication Possible? [ucr.edu] for a more detailed answer.

    • Re: (Score:2)

      by mbone ( 558574 )

      There is a lot of evidence for the universe being in an early, condensed, hot state - as you say, the CMB is a one of them, as is the success of Big-Bang Nucleosynthesis (BBN). If that is what is meant by the "Big Bang," then it is indeed well established. If, however, what is meant is there was some sort of singularity from which everything exploded than that, like the smile of the Cheshire Cat, seems to be receding into the distance or fading away.

      This can be most clearly expressed by asking, how old is t

    • All of the data that could support "Big Bang" is edge data, and therefore known to be inaccurate. For every sensor, the resolution drops off at the edge. If Big Bang is true, it would be like God theories that can't be proven, because you can only hope to get edge data.

      That it is taught as a "fact" instead of as an unprovable hypothesis shows the difference between actual physics, and cosmology.

      Actual physics is making predictions at the small scale that is not edge data, and where the predictions match obs

  • Backpeddle? (Score:5, Insightful)

    by jythie ( 914043 ) on Sunday June 22, 2014 @09:55AM (#47292817)
    I am not sure "back pedal" is really the right word here. They did some research, published a result, other researchers pointed out potential problems with the conclusions, the original team listened to the criticisms and took them seriously.

    • Re:Backpeddle? (Score:5, Insightful)

      by Tanktalus ( 794810 ) on Sunday June 22, 2014 @10:02AM (#47292847) Journal

      This.

      Real science is always open to upending. If they weren't willing to listen to critics, they'd be called a religion.

      Excersise for the reader: are there any other scientists not willing to listen to their critics?

      • Re: (Score:2)

        by dryeo ( 100693 )

        Scientists are human and can have the same flaws as any human. There are lots of scientists who have held onto their beliefs in the face of new evidence which is why it has been stated that for new scientific paradigms to be generally accepted needs a new generation of scientists to replace the old established ones. There is the ideal of a scientist, then there is the reality of humans playing scientist.
        Famously there is Einstein refusing to accept quantum, Fred Hoyle refusing to accept the big bang and ins

    • Re: (Score:1)

      by Anonymous Coward

      indeed, that's what science is - adjusting theories to fit observations. As opposed to religion - adjusting the data to conform to dogma.

    • Re:Backpeddle? (Score:5, Informative)

      by Charliemopps ( 1157495 ) on Sunday June 22, 2014 @10:32AM (#47292961)

      I am not sure "back pedal" is really the right word here. They did some research, published a result, other researchers pointed out potential problems with the conclusions, the original team listened to the criticisms and took them seriously.

      Right... its even less serious that you make it out to be.

      A dumbed down explanation of how it went:
      Researchers: "We finally have conclusive evidence of Inflation!"
      Critics: "That's pretty cool but did you consider X?"
      Researchers: "Yes, but we're not ready to publish all the data yet. If we do, someone might beat us to some other stuff we're working on"
      *data finally published*
      Critics: "Ah, you did account for X. You're probably correct, but X could possibly be bigger than you accounted for in some rare cases."
      Researchers: "Ah, we see your point now. Ok, this isn't conclusive evidence... but it's pretty darn close. There's another group that's very close to completing a study that will confirm our observation so we'll just wait for them as it will come sooner than anything we can do."

      • Researchers: "We finally have conclusive evidence of Inflation!"
        [runs off to make a viral video]
        Critics: "That's pretty cool but did you consider X?"

        tftfy

      • The way you script things there isn't exactly science either.

        Science isn't supposed to have an agenda and then set out to prove the agenda, nor is it supposed to sit around and wait for others to sit around and prove it either. The scientific method calls for the formation of a hypothesis and then doing a series of tests that will attempt to disprove that hypothesis. True science requires standing up to the scrutiny of scientists attempting to disprove their own thoughts and ideas not holding back fact

        • Re: (Score:2)

          by fnj ( 64210 )

          The scientific method calls for the formation of a hypothesis and then doing a series of tests that will attempt to disprove that hypothesis.

          I would modify that slightly. For "disprove", substitute "support or oppose". The solar eclipse observational experiments of Campbell, Eddington and others were undertaken in a thirst for knowledge to FIND OUT if one phenomenon predicted by general relativity was actually evident; not really to try to prove or disprove general relativity. If the measurements of positio

    • Re: (Score:2)

      by mbone ( 558574 )

      Actually, they did some research, had a press conference, other researchers pointed out potential problems with the conclusions, and they put some weasel words in the actual published paper. It doesn't matter; the way they went about this, and the weakness of their dust calibration, means that no one will really believe the cosmological interpretation of their results* until more data comes along. That may not take long, according to Nature News [nature.com] :

      In addition, presentations given earlier this week at a cosm [iki.rssi.ru]

    • I do think they jumped the gun a bit by getting their background correction from a scraped conference figure rather than unambiguous published data, which seems to be the source of the problem.

  • These BICEP2 guys didn't back-pedal of their own accord, friends---how about citing the much more senior and respected people, such as WMAP guru Spergel [arxiv.org], who already DID the joint Planck analysis and showed them how hasty they had been? This is pretty poor reporting on NS's part.

    BICEP2 were a bunch of young upstarts riding into town with guns a-blazing. The sheriff came down and told them to calm down, boys, calm down.

    • They were for the bang before they were against it.

    • BICEP2 were a bunch of young upstarts

      You got that right. And the tender egos of the Planck team got hurt by the "young upstarts" outdoing them. Awww, how sad.

      Fact is, the BICEP2 team got the result and published in a leading journal. The team hardly backtracked at all. For more on this, see the blog post by Lubos Motl: "BICEP2 gets published in PRL [blogspot.co.uk]".

      It is pathetic how established scientists try to protect their egos from "young upstarts".

      • Re: (Score:2)

        by mbone ( 558574 )

        If anyone had any doubt that Lubos Motl has no credibility at all, that post proves it IMHO.

  • I still find it hard to believe that they would do a major press conference on results that depended (fairly crucially) on a calibration screen-scraped from a presentation from another scientific group. I would love to know the true back-story here - was knowledge of this dependency on screen-scraped data widespread within the BICEP2 group, or was this just some grad student who was being expedient? Didn't anyone try and contact the Planck group and ask for their best dust estimates?

    While it is quite possib

    • Planck has yet to release their polarization data, so BICEP2 couldn't use it. To be clear, they also didn't use just the Planck data: the paper lists five different models for dust polarization, only one of which (DDM1) was constructed from what little Planck data they had available. All of them showed fairly tiny amounts of polarization from dust compared to their signal, hence the conclusion that it was a cosmological polarization (there were other reasons for that conclusion as well, of course). They pub

      • Re: (Score:2)

        by mbone ( 558574 )

        Yeah, but when you lead with a press conference, and then have to back-pedal, you are going to take a hit, and they have.

  • The foreground dust in the Milky Way just happens to have a pattern of polarized light filtering capabilities that align with the largest grain structure of all the mass in the visible universe on the order of 5 sigmas from our current position. Coincidences like that happen all the time. It is a quirk of timing. In a few hundred years the Earth's position will have shifted enough that this "Ray-Ban effect" will disappear.
  • Comment removed based on user account deletion

  • The advantage to science (Score:3)

    by nurb432 ( 527695 ) on Sunday June 22, 2014 @12:19PM (#47293447) Homepage Journal

    Is that it admits when its wrong. Religion, not so much.

    • Re: (Score:1)

      by Anonymous Coward

      Science: "The data doesn't fit the theory? Fine, we'll come up with another theory."
      Religion: "The data doesn't fit the theory? THE DATA'S WRONG!"

  • "A few months ago researchers announced they had discovered proof of the big bang"

    They were actually looking for evidence of cosmic inflation, as this would account for how the universe is isotropic, or the same over vast distances, something big bang doesn't account for.

  • I remember that at the time this was annouced, and especially in slashdot and the linked article we were told to take the story with a grain of salt. Oh well, seems the slashdot blurb didn't but the article included : “These results are as extraordinary as they get, and they will require the most extraordinary scrutiny,” Kamionkowski said. (...)

    Maybe slashdot comments were better at pointing out these were initial, preliminary etc. results. The general media failed to put any nuance and announc

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