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Science

Inflaton, Mother of the Universe 163

quantalm writes "Forget the god particle, we're talking about the universe's particle mother. The theory of supersymmetry has rolled out two new ideas about the particle that puffed spacetime up from smaller than a proton to bigger than a soccer ball: it could be the 'unified particle' of Grand Unified Theories or a smaller-scale version that could be tested at the Large Hadron Collider at CERN."
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Inflaton, Mother of the Universe

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  • inflaton? (Score:5, Funny)

    by circletimessquare ( 444983 ) <circletimessquar ... m ['gma' in gap]> on Thursday August 19, 2010 @11:53AM (#33303438) Homepage Journal

    i don't know about unifying electromagnetism and gravity, but it seems like someone just unified economics and quantum mechanics

    just tell us how to avoid the deflaton particle for the next few years

    • by Monkeedude1212 ( 1560403 ) on Thursday August 19, 2010 @11:59AM (#33303526) Journal

      If those two particles meet, they don't cancel out - they actually cause a rift in the space-time continuum that is so catastrophic that it convinces people to take out sub-prime home equity loans.

    • You do realize that quantum economics is an actual field of study, right?
    • You want to avoid deflation?
      You're stupid.

      While very rapid deflation is bad (as markets cannot react instantly), deflation as a whole is in fact a good thing for everyone but the top 1% of wealthy people.

      • Re: (Score:3, Insightful)

        by Mr2001 ( 90979 )

        Deflation is bad for anyone who has any debt, which is an awful lot of people. The amount you owe is specified in nominal dollars, so deflation means you have to pay back a greater real value than you would otherwise.

        It's also bad for anyone who runs a business, or works for a business, which again is an awful lot of people. Deflation -- or rather, the expectation of more deflation to come -- makes people less willing to spend money. I don't want to buy ten widgets for $10 today if I think I can get eleven

        • An awful lot of stupid people.
          Debt is to be avoided like the plague.

          • by Mr2001 ( 90979 )

            There are around 50 million mortgages in the United States. If everyone followed that philosophy, a lot fewer people would be able to own houses... or own cars, or start businesses and expand them, etc.

            Like it or not, there is a place for borrowing, and we'd all be worse off without it. Well, maybe not the top 1% of wealthy people you mentioned earlier -- they can avoid debt like the plague, because they have cash in the bank to cover the expenses that ordinary people need loans for.

            • There are around 50 million mortgages in the United States. If everyone followed that philosophy, a lot fewer people would be able to own houses... or own cars, or start businesses and expand them, etc.

              Protip: Those people are NOT able to own the houses or cars they bought. That's why they're in debt. That's why we're fucked.

              • Bullshit. It just means they can't own it straight away. They might still be able to afford it over the long term.

                • And I might be able to afford a McMansion.
                  The bank is willing to loan me the money, and I'm sure to get that promotion, and my wife's on the pill so no more kids, and my parents are nice and healthy, and I'm nearly done paying off my car...

                  Retards, the lot of you.

              • by Mr2001 ( 90979 )

                Sure, you could save up your cash and buy a house when you're 60 instead of getting a 30 year mortgage when you're 30. But that means you lose the use of the house for those 30 years, and the money you save in mortgage interest, you lose in paying rent on another place for 30 years!

                Likewise, you could save up your cash and expand your business 5 years from now instead of getting a loan and expanding today. But you might find that competitors have already taken your spot by then, either because they have mor

                • Protip: You're a moron.

                  A 5 year loan is fine.
                  30 years is fine if you plan to WORK for 30 years, at your CURRENT salary, pay it off ON TIME, and STILL have enough money over the years to handle the $XX,XXX in expenses you WILL incur to cover medical expenses, car expenses, etc.

                  Every single person under the water right now bit off more than they could chew, and it's their own fault for being haphazard, ignorant, or plain fucking stupid.

                  Gradual deflation would NOT have a terrible impact on anyone in the middl

      • Or anyone in a lot of debt, I imagine.

    • by sorak ( 246725 )

      i don't know about unifying electromagnetism and gravity, but it seems like someone just unified economics and quantum mechanics

      just tell us how to avoid the deflaton particle for the next few years

      Misused quantum mechanics: the branch of quantum physics that accounts for bullshit at the atomic level; an explanation of nonsensical beliefs based on a poorly understood field.

  • by MaggieL ( 10193 ) on Thursday August 19, 2010 @12:08PM (#33303648)

    "Oops. Sorry about those extra universes that just leaked out."

  • by Xacid ( 560407 ) on Thursday August 19, 2010 @12:10PM (#33303676) Journal

    My initial reading of the subject:

    Inflation of Mother, like a Universe.

    • by ruiner13 ( 527499 ) on Thursday August 19, 2010 @12:21PM (#33303866) Homepage
      Your mom is so inflated, your dad had to roll her in flour and find the wet spot.
      • by Quiet_Desperation ( 858215 ) on Thursday August 19, 2010 @12:41PM (#33304200)

        Your mom is so inflated, your dad had to roll her in flour and find the wet spot.

        Nah, you need to go full on physics here.

        "You mom is so inflated, your dad had to roll her up like a Calabi-Yau manifold and look for the Casimir effect!"

        Thank you! Am I right? Huh? Huh? Am I? Huh?

        Oh, shut up.

      • by AP31R0N ( 723649 )

        i wrote these for a Fark thread a few days ago:

        Yo mama so fat i swerved to miss her and ran out of dilithium crystals.

        Yo mama so fat the guild navigator needed 30 kilos of spice to see around her fat ass.

        Yo mama so fat her measurements are 36AU-26AU-36AU, and her other arm is just as big.

        Yo mama so fat and so black she the missing dark matter.

        Yo mama so ugly the universe is expanding to get away from her.

        Yo mama so black her black body radiation is 0*.
        * doesn't actually claim to understand black body radiat

    • by t35t0r ( 751958 )

      yeah, except that the universe tends to go to a steady state (the opposite of inflation)

      • Yeah, accept the universe is accelerating (the opposite of going to a steady state).

        • Re: (Score:3, Funny)

          by Bigjeff5 ( 1143585 )

          Yeah, accept...

          Oh shit!

          *runs from the grammar nazis*

          • You could have left it alone and then if somebody jumped on you could have claimed you were making an imperative like 'accept it!' However, now you have convicted yourself. Smooth move, Exlax.
  • Why do they say "mother" particle? Is it because mothers have a tendency to inflate after giving birth and getting married? ;-)
    • During this period in the big bang, particles had not formed yet. If you view the universe at this stage as a single particle (which you could, since it contains all energy and mass in the universe in a single entity), it creates all the other particles, but more than that it is the beginning of our current universe.

      AKA, the mother of the universe, mother of all particles, mother of all matter, etc.

    • by mcgrew ( 92797 ) *

      It's the particle that gave birth to the universe. From the very first sentence of TFA: "The inflaton particle is credited with generating the universe and fuelling its inflation."

  • by bjorniac ( 836863 ) on Thursday August 19, 2010 @12:48PM (#33304304)

    The "inflation" we're talking about here is the accelerated expansion of the early universe. So, first off why do we need it?

    It turns out that parts of the observable cosmic microwave background are 'causally disconnected'. This means that you take two patches of sky as observed at the time the CMB formed (300k years after the big bang, we now think - approximately 15 billion years ago) and track their behavior back to the big bang. In the normal models where the universe is full of dust or radiation they never were in contact in the past: Light from one area could never reach another. Why is this a problem? Because they are remarkably similar. They appear to have come into thermal equilibrium (same temperature) yet this shouldn't be possible if they were never in contact. So we need to have a method by which the universe expanded faster before this period.

    There are a few ways to do this - one is a cosmological constant. But the problem with a constant is that it's constant - we should still see it today, and we don't. The universe is not expanding that fast anymore - the bounds we can place on the cosmological constant today put it well below the effect we want from inflation. What we need is something that acts like a cosmological constant for a while and then drops away. This is what inflationary models are all about. The inflaton is a theoretical particle that starts off behaving like the comsmological constant, but eventually decays into the matter we see today. We model this by a particle moving in a potential - think of a ball rolling on the side of a hill. How the inflaton behaves is all about the ratio of its kinetic to potential energy - high potential energy looks like a cosmological constant, high kinetic energy looks more like normal matter. (I can explain this in more detail if anyone's interested). So the ball rolls down the hill, losing potential, gaining kinetic (there's also friction from the expansion of the universe so it loses 'energy' overall) and hence our inflaton does exactly what we need - slowly changing from looking like a cosmological constant to normal matter. In theory too, it decays once it reaches the bottom of the hill, but no-one provides much of a model for this.

    This is old (20-30 years old is old in theory standards) stuff from Linde, Mukhanov etc. No-one would take it seriously, except that when you calculate things from it, it works incredibly well - it's the source of http://xkcd.com/54/ [xkcd.com] - it's still controversial. Some people love it, others think it's a fudge and doesn't do much for you. The new stuff here is that there is a method being proposed by which a multiplet of supersymmetric particles (again, I can say a bit more but it's not my field) is shown to be able to act like the inflaton. Ie a stable state of multiple particles bound together could act this way, and could be found at the LHC. Now, that's a lot of 'could' - the usual inflaton mass is set to around 10^12 GeV - way above what the LHC can reach, and this is the same across most inflationary models. But if the LHC can see evidence of supersymmetry (again, another discussion, but it is thought to be likely that if supersymmetry is real then the LHC will see it) it might be able to at least give some credibility to some of these models of inflation.

    • Re: (Score:3, Informative)

      No-one would take [inflation] seriously, except that when you calculate things from it, it works incredibly well - it's the source of http://xkcd.com/54/ [xkcd.com]

      Not quite. You don't need inflation to get the blackbody spectrum of the cosmic microwave background radiation (CMBR) observed by the COBE satellite, which is what the xkcd comic depcits. That's a prediction of plain vanilla Big Bang cosmology, with or without an early inflationary phase.

      However, inflation does predict details in the CMBR angular power spectrum, the "acoustic peaks", which were observed by the later WMAP satellite. And it solves other "paradoxes", like the horizon problem you mention.

    • Light from one area could never reach another. Why is this a problem? Because they are remarkably similar. They appear to have come into thermal equilibrium (same temperature) yet this shouldn't be possible if they were never in contact. So we need to have a method by which the universe expanded faster before this period.

      Maybe they have the same temperature because they were made/subject-to a similar environment, simply because they shared a similar history and so changed in similar ways.

      Alternatively they could have been entangled (quantum spooky action at a distance), although the high energies would probably have broken entanglement, but maybe things were different back then.

      • Similar environments and histories has been posited a number of times, but given just how similar the regions are and how many of them there are it doesn't seem likely. But more so, this only pushes the question further back: Why were their histories identical? Did they all start in roughly the same state? Why? And at the same time?

        Entanglement requires causal contact. Two particles are entangled when they have been in contact, and then move apart, so this doesn't help.

        • But I thought that the point of the big bang was that the universe started out from a single point, so everything (or the precursor to everything) was in one place -- ie everything in contact with everything else???
          • Re: (Score:3, Interesting)

            by bjorniac ( 836863 )

            Ah, now you're into the fun stuff: Just about every physicist believes that general relativity will have to be modified by quantum mechanics at some stage and at least once you get to energy densities around the planck density (this value comes mostly from dimensional analysis - it's more of an order of magnitude thing). Since the standard big bang that results from GR has infinite density, we believe that corrections will happen before you get there - that quantum mechanical effects take place and that we

    • > They appear to have come into thermal equilibrium (same temperature) yet this shouldn't be possible if they were never in contact.

      This has always bothered me, and I'm certainly not trained in these disciplines so that may be the sole reason, but ... why should 2 areas *NOT* be the same temperature simply because they haven't "met"? It's impossible that 2 things in the early universe can't have *independently* arrived at the same state?

      • Well, it's not just two areas, it's any two areas. If the model you're considering doesn't have inflation, the number of patches of sky that are causally past disconnected yet have the same temperature is of the order of a million. Two things independently reaching the same state is a curiosity (well, it depends on how close they are really, but we'll let that go for now). A million things on the other hand, well, that's more than just curious.

        • I guess I haven't studied it enough and I don't have the requisite background. I understand what you're saying from a mathematical point of view, but I guess my gut just doesn't understand why something that expanded from ~the size of a proton can't show homogeneity without a hyper inflationary phase. I'll keep reading the comments here to try and get a sense of it. Thanks for your patience!

  • SUSY appears to be an extraordinary gratuitous abbreviation for a perfectly understandable word - supersymmetry. Physics is hard enough to keep up with. I don't understand half of what Physicists say (except Susskind), no need to use secret code. I guess that's what I get for RTFA.

A committee takes root and grows, it flowers, wilts and dies, scattering the seed from which other committees will bloom. -- Parkinson

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