Results 1 to 9 of 9

Thread: Antimatter

  1. #1
    Join Date
    Aug 2004
    Posts
    55

    Antimatter

    Why is matter dominating the universe? I thought there was always a conservation of the baryon no. (no. of quarks+antiquarks /3) Then how can our baryon no. be +ve & not 0? Was this anomaly done at the Big Bang? Can there be antimatter stars spewing out antineutrinos with complete galaxy systems with atoms and nuclei? What would their composition be? Or is antimatter just a mathematical quirk about the –ve roots of
    E^2=m^2*c^4+p^2*C^2
    If so does antimatter have –ve mass or –ve charge/spin?

  2. #2
    Join Date
    Sep 2005
    Location
    Metrowest, Boston
    Posts
    4,216

    Cool the big question....

    Quote Originally Posted by mercury
    Why is matter dominating the universe? I thought there was always a conservation of the baryon no. (no. of quarks+antiquarks /3) Then how can our baryon no. be +ve & not 0? Was this anomaly done at the Big Bang? Can there be antimatter stars spewing out antineutrinos with complete galaxy systems with atoms and nuclei? What would their composition be? Or is antimatter just a mathematical quirk about the –ve roots of
    E^2=m^2*c^4+p^2*C^2
    If so does antimatter have –ve mass or –ve charge/spin?
    Mercury. Kudos.The presently observed universe universe has no reason to exist whatsoever. You have asked one of the biggest questions in physics/cosmology. Nobody has any experimental evidence whatsoever to show why an excess of baryons over anti-baryons is present. Proton-decay experiments showed them stable beyond ~1031 years...All particle physics experiments show associated production of pairs(one of each matter/anti-matter)every time, trillions of times after times. Though some gamma rays from annihilations exist in high energy astrophysical situations, there is no indication that it is anything other than normal pair annihilation....not matter-galaxy vs antimatter-galaxy annihilation.
    Time delays in B-meson decays only shows that there is an asymmetry in their rates...not in the eventual production of an excess of matter or anti-matter......and all those experiments are done in the presence of the neutrino sea plus the local solar neutrino flux. Would that we could perform that experiment at ~500 A.U. and see if the difference in the rates varies due to the ambient neutrino sea gradient being different. I doubt that the Earth's slight distance variation over the year will show enough change to measure, though like many parity asymmetries, it is possible nobody has had it checked yet. Pete.

  3. #3
    Join Date
    Feb 2004
    Posts
    576
    Quote Originally Posted by mercury
    I thought there was always a conservation of the baryon no.
    Baryon number is not concerved by the weak interaction, in rare cases (see The Standard Model of electroweak interactions has all the necessary ingredients for successful baryogenesis. ... Baryons are not conserved by the usual electroweak interactions due to quantum chiral anomaly.

    See also the last section in this page: "...the observed matter-antimatter ratio may have been produced by the occurrence of CP violation in the first seconds after the big bang,..."

    Quote Originally Posted by mercury
    Can there be antimatter stars spewing out antineutrinos with complete galaxy systems with atoms and nuclei?
    Regular matter spits out anti-neutrinos during beta decay. Might there be antimatter stars in large anitmatter regions? No, that's been ruled out. We would have noticed them.


    Quote Originally Posted by mercury
    Or is antimatter just a mathematical quirk
    It is real. Anti-electrons are used in medical imaging (PET scans)! Experimentors commonly create antimatter to smash head-on with matter, as the preferred way of concentrating a lot of energy in a small volume.

    Special Relativity requires that anti-particles exist.


    Quote Originally Posted by mercury
    If so does antimatter have –ve mass or –ve charge/spin?
    An anti-particle has the identical mass as its normal counterpart. Mass only goes in one direction, and electrons and positrons both have it. Quarks and anti-quarks both have it. In baryons, most of the mass comes from binding energy, which I'm sure you see is the same regardless. Likewise, the mass due to kenetic energy of motion will be the same regardless of whether it is matter or anti-matter.

    --John

  4. #4
    Join Date
    Sep 2005
    Location
    Metrowest, Boston
    Posts
    4,216

    Cool not yet...

    [QUOTE=John Dlugosz]Baryon number is not concerved by the weak interaction, in rare cases (see The Standard Model of electroweak interactions has all the necessary ingredients for successful baryogenesis. ... Baryons are not conserved by the usual electroweak interactions due to quantum chiral anomaly.

    John Dlugosz: The theoretical posture of chiral anomaly has as yet no experimental confirmation from a particle physics lab anywhere in the world. It will be Nobel material should such data be found. Since the first cosmic ray photographic emulsion searches...right up til now, every bubble chamber photo, every spark chamber, every wire chamber....every detector yet...no asymmetry in matter over anti-matter production. Like supersymmetry, it is an idea totally without corroborating experimental confirmation. Pete.

  5. #5
    Join Date
    Feb 2004
    Posts
    576
    Supersymmetry is still an idea and a work in progress. Electroweak theory is sound, matches all observations, and spits out QED as a subgroup in the low-energy case. Furthermore, although we've never observed the chiral anomaly in a cloud chamber, the Feynman diagram shown on that page is the spitting image of one of the 5 canonocal "closed loop" forms figured into renormalization. If that form didn't "exist" as a possibility, the sum would come out wrong, right?

    IAC, reference 5 on that page might be a good direct answer to the original poster's question. "Moreover the standard electroweak theory predicts nonconservation of baryonic charge through quantum corrections. This nonconservation is negligibly small at low energies but could be very much enhanced at high temperatures comparable with the electroweak scale"

    --John

  6. #6
    Join Date
    Nov 2005
    Posts
    1,023
    Quote Originally Posted by mercury
    Why is matter dominating the universe? I thought there was always a conservation of the baryon no. (no. of quarks+antiquarks /3) Then how can our baryon no. be +ve & not 0? Was this anomaly done at the Big Bang? Can there be antimatter stars spewing out antineutrinos with complete galaxy systems with atoms and nuclei? What would their composition be? Or is antimatter just a mathematical quirk about the –ve roots of
    E^2=m^2*c^4+p^2*C^2
    If so does antimatter have –ve mass or –ve charge/spin?
    If quantum theory is correct the "domination" by matter is not as overwhelming as you might think. The quantum vacuum is predicted to have expansive presssure ~120 OOM larger than observed, and it is predicted to have gravitational equivalence ~120 OOM greater than observed. These forces are apparently in dynamical balance everywhere throughout the universe.

  7. #7
    Join Date
    Sep 2005
    Location
    Metrowest, Boston
    Posts
    4,216

    Wink climbing out on a limb...

    Quote Originally Posted by turbo-1
    If quantum theory is correct the "domination" by matter is not as overwhelming as you might think. The quantum vacuum is predicted to have expansive presssure ~120 OOM larger than observed, and it is predicted to have gravitational equivalence ~120 OOM greater than observed. These forces are apparently in dynamical balance everywhere throughout the universe.
    It's interesting to see a theory off by 120 orders of magnitude, and still have proponents, but then again, somebody paid for the grilled cheese sandwich "Mona Lisa"...~ $13,000..
    Pete.

  8. #8
    Join Date
    Nov 2005
    Posts
    1,023
    Hi, Pete:

    It is instructive to watch the on-line videos of Roger Penrose's lectures to see why this might be an important point to pay attention to. In the ATM section, I have instituted a thread entitled "What if a non-scientist..." but that thread has been essentially killed for now. I have posted a number of critical falsifications that can disprove my model (which mainsteam astonomers will not do), and I now await experimental confirmation of my predictions.

  9. #9
    Join Date
    Aug 2004
    Posts
    55

    Cool Anyway, coming back to the point about antimatter...

    We can't calculate the baryon no. of balck holes, right? So what if the antimatter systems have already become black holes? (Don't ask me how!) Also astronomically seeing far away is seeeing back in time so why don't our Hubblers just look far far away to know more truths about the Big Bang or the end of antimatter?

Similar Threads

  1. Ep. 74: Antimatter
    By Fraser in forum Astronomy Cast
    Replies: 7
    Last Post: 2008-Feb-08, 02:27 AM
  2. Where is the antimatter gone ?
    By czeslaw in forum Against the Mainstream
    Replies: 13
    Last Post: 2005-Mar-06, 04:13 PM
  3. Antimatter
    By Deep_Eye in forum Space/Astronomy Questions and Answers
    Replies: 2
    Last Post: 2004-May-31, 05:35 PM
  4. Antimatter
    By Powerman 5000 in forum Off-Topic Babbling
    Replies: 14
    Last Post: 2004-Feb-11, 12:35 AM
  5. Antimatter
    By mercury in forum Against the Mainstream
    Replies: 0
    Last Post: 1970-Jan-01, 12:00 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
here
The forum is sponsored in-part by: