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Suppose you had 80% up quarks, and only 20% down quarks. How would this affect stellar formation?

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I'm not sure this question is really answerable in its current form. Why would there be 80% up quarks and 20% down quarks? –  David Z Apr 6 '13 at 7:47
@DavidZaslavsky this looks like a legitimate question to me. It is not relevant to know what processes could potentially lead to such an unusual up/down quark ratio. But the expected answer can discuss what impacts the up/down quark ratio has on stellar formation. Such and similar questions (or Gedankenexperiments) are legitimate in the "real world" and discussed by serious physicists doing accepted main stream physics. I countervoted the undeserved downvote. –  Dilaton Apr 6 '13 at 10:39
Can people please stop downvoting this legitimate question? The question is clear, if the reader does not understand it it is his own fault. The increase of very capricious downvotes on this site is distracting. –  Dilaton Apr 6 '13 at 15:39
Thanks, Dilaton. It is a problem on all stackexchange sites. –  Buttle Butkus Apr 12 '13 at 6:44

1 Answer 1

up vote 3 down vote accepted

It's really not clear what hypothetical limits you're imposing. I take your question to mean that in the process of baryogenesis the various baryons like protons and neutrons highly favored up quarks (lots more protons than neutrons). Remember, quarks are subject to confinement so other than a quark-gluon plasma, quarks are confined to baryons.

Since stellar formation depends on hydrogen and hydrogen formation depends on protons and electrons primarily, it's unlikely that there would be any meaningful impact.

Also, remember that free neutrons are unstable and will undergo beta decay and convert to protons. If there is an excess of protons the reverse can happen via electron capture.

I'm pretty sure even if there were some wild physical law that forced there to always be a huge imbalance of up to down quarks there would still be enough hydrogen formation for stars to form. It's not clear what this restriction would do to hydrogen to helium fusion though.

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It is not in my area of expertise, I am an experimentalist, but my intuition is that if there were an unbalanced number of free quarks the universe would stop expanding at the time of baryogenesis, due to the infinite attractive force of the free quarks. They are free in the initial soup because of the dimensions and energy and asymptotic freedom afaik. –  anna v Apr 6 '13 at 3:24
Well this is certainly not my area of expertise either. I assumed any unbalance in the quarks would pair up to form meson and baryons. Without anti-quarks to pair up though I don't think mesons could form. You may be right that with too many excess unpaired quarks would immediately stop inflation. –  Brandon Enright Apr 6 '13 at 7:02

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