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Second and Third Generations of Proton and Neutron?

  1. Nov 16, 2008 #1
    Hello!

    I have a very interesting question, whose answer I have not yet been able to find out.

    Now, according to The Standard Model there are three generations of matter, therefore three generations of quarks also.

    Generations of Quarks:
    1st: up (u) & down (d)
    2nd: charming (c) & strange (s)
    3rd: top (t) & bottom (b)

    There are also three generations of corresponding Leptons:
    1st: electron (e−) & electron-neutrino (νe)
    2nd: muon (μ−) & muon-neutrino (νμ)
    3rd: tauon (τ−) & tauon-neutrino (ντ)

    So, we also know that the proton is u+u+d and the neutron is u+d+d.

    Therefore who knows how we could find out about the physical and quantum mechanical properties of the second and third generations of proton and neutron, that is:

    ???? PROTON & NEUTRON
    1st: uud & udd
    2nd: ccs & css
    3rd: ttb & tbb

    And if we have these higher energy protons and neutrons, we could build second and third generations of chemical elements, that is:

    1st: H(=uud), He(=2uud+2udd), Li(=3uud+4udd), etc.
    2nd: **H(=ccs), **He(=2ccs+2css), **Li(=3ccs+4css), etc.
    3rd: ***H(=ttb), ***He(=2ttb+2tbb), ***Li(=3ttb+4tbb), etc.

    You would have to, of course, add the corresponding electrons, muons and tauons to their respective generational elements to get all your periodic table chemically stable.

    Now, my question is:
    Is it all possible, even if only theoretically?
    Does the Standard Model predict this?
    Or String Theory?

    Please answer me, because I believe this could initiate a very exciting new path of research (both theoretical and later even experimental...)

    Thank you!!!!
     
  2. jcsd
  3. Nov 16, 2008 #2

    Fredrik

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    I think the problem is that these states are all very unstable. They will decay into first generation particles almost immediately, just because they can.
     
  4. Nov 16, 2008 #3

    malawi_glenn

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    Also you can't have any top quarks bound in hadrons..
     
  5. Nov 16, 2008 #4
    I understand that is the most likely thing that can happen, but then there is the so-called "Island of Stability" at the far end of the periodic table, which implies that even very high energy elements could be yet stable...
     
  6. Nov 16, 2008 #5

    malawi_glenn

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    The theoretical obtained "island of stability" is that certain configurations of protons and neutrons are stable. So you should not confuse these two subejcts.

    However, there are research within your suggestion of "exotic nuclei", google hypernuclei for instance. They are very shortlived.

    You can pick up an advanced textbook in hadron physics and study this if you want. I can give you some tips.. but it is very technical.
     
  7. Nov 16, 2008 #6
    So, why can't top quarks be bound in a hadron?? (the strong interaction keeps the quarks in the proton and neutron also...)
     
  8. Nov 16, 2008 #7

    malawi_glenn

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    because they are so short lived that they decay before any kind of hadronization process can take place.

    You might want to study som "basic" particle physics.. try the textbook "Particle Physics" by Martin. Very good!
     
  9. Nov 16, 2008 #8
    so are you suggesting then, that theoretically they might be possible... but these hadrons may not exist on our time scale... (what about the time scale of string theory?)
    how long would the "hadronization process" have to take?

    thanx, and you have any more books on hadrons, you'd recommend?
     
  10. Nov 16, 2008 #9

    malawi_glenn

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    if you don't know anything about quantum physics or particle physics, I suggest you start with the basics before suggesting new areas of research ;-)
     
  11. Nov 16, 2008 #10
    look, i've just read a very interesting article about a new particle (composed of a charming and a strange quark), and surprisingly, they found that it lived much longer than what theory had previously suggested... (a heavier and more stable particle than in theory!)

    http://www.theregister.co.uk/2004/06/18/meson_weirdness/

    so, how do you explain that?
     
  12. Nov 16, 2008 #11

    malawi_glenn

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    explain what? It just "violates" the general rule that the heavier a particle is, the faster it decays. So what?

    It lives 3 times longer than it "should be" according to simple estimation models, they live 3*10^20 seconds instead of 1*10^10 s.

    And is not even a scientific article, is the particle listed in PDG?

    I am studying the pi0 decay into e+e-, which have a braching ratio 3 standard deviations from the standard model value according to quantum electro dynamics.

    Are you suggesting that since we don't know everything, everything is possible?
     
  13. Nov 16, 2008 #12
  14. Nov 16, 2008 #13

    malawi_glenn

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    and this you think give arguments for having nuclei of hyperons? ;-)
     
  15. Nov 16, 2008 #14
    i wasn't talking about hyperons (any baryon containing a strange quark, but no charm quarks or bottom quarks!) but such discoveries (that contradict accepted dogmas) could open a very narrow but extremely important window into yet unexplored territory (eg.: the strange & charming and the top & bottom analogues of the proton and neutron), string theory, for instance suggests even more generations of matter than the usual three...
     
  16. Nov 16, 2008 #15

    malawi_glenn

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    That is just the way science goes.

    Now the question you have raised is an old one, so there is a lot which can be studied in this field..

    Why is this an important and unexplored territory? Hunts for beauty baryons etc have been going on since decayes...

    String theories suggest alot of things.. so what?
     
  17. Nov 16, 2008 #16
    if neither of your (even the very technical) textbooks mention scc, ssc, btt or bbt then wouldn't it be unexplored or perhaps somewhat ignored territory?

    why would it be important? wouldn't a 2nd and/or 3rd generational equivalent of the periodic table be interesting? couldn't some new chemistry and/or technology come out of that?

    and the "island of stability" in the study of super-heavy elements, don't you see how it's kind of analogous to super-heavy particles, and baryons composed of them?

    symmetries, analogies and elegance have always been important driving force into new research in physics, so why not especially these?
     
  18. Nov 16, 2008 #17

    malawi_glenn

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    i) they are very very very short lived and very very hard to detect. There is a STRONG motivation for not having t-quarks bound in hadrons.

    ii) technology of particles living shorter than 10^-30s?

    iii) there is a small analogy. The difference is that you don't even have particles with bbs configuration, you want to merge them togheter to form nuclei..

    iv) There is already strong research in hadron physics, if you havn't noticed. However, one must be realistic when doing research and proposing new fields of study.
     
  19. Nov 16, 2008 #18

    Vanadium 50

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    First, the nuclear island of stability is believed to be an island of relative stability. Nucleii there are expected to live 100 or 1000 times as long as their neighbors, but that still gives them half-lives of seconds or minutes.

    Second, you have given no argument whatever that the particles you propose are in a new island of stability,

    Third, you have given no argument why your putative new island of stability confers a lifetime 100000000000000000000 or more times longer than expected, which is what it would take for useful materials to be made from them.

    I think malawi_glenn made a very good point: "if you don't know anything about quantum physics or particle physics, I suggest you start with the basics before suggesting new areas of research."
     
  20. Nov 16, 2008 #19
    alright then, but what chance do you give the newly starting Large Hadron Collider in Geneva, that it will discover super-heavy baryons that will be much more stable than expected?
     
  21. Nov 16, 2008 #20

    malawi_glenn

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    they will not even search for super heavy baryons... as far as I know, it is not on their agenda.

    And what factor is "more stable than expected" ?
     
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