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I recently read about the early universe and found that first quarks were made $10^{-12}$ seconds after the inflation or the beginning.

But what was the cause of this minute delay, since inflation started when the universe was $10^{-34}$ seconds old (as per this image).

image

So basically I want to know why did it take that much time to form the first quarks? Also how much time should it take energy to form quarks at laboratories?

I know that nothing sure can be said about this but I want some ideas regarding this. Also, the time intervals are approx values given on the websites.

Edit: why didn't we have a massive quark (more massive than top quark or even anything else) if too much energy was present in a small space??

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Above a certain temperature, quarks get annihilated as quickly as they form. the universe had to cool off a bit to get below that threshold temperature, so the quarks would persist. Then they acquire their mass at about 10^-12 seconds.

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  • $\begingroup$ By temperature did you mean that a huge amount of energy was present in a very compact space (since temperature is the measure of internal energy of the molecules and there were no molecules) ?? Also if a huge amount of energy was present then why didn't they form a massive quark ?? $\endgroup$ – Ankit Aug 8 at 8:19
  • $\begingroup$ $10^{-12}$ s is when quarks attain their mass. It is not the epoch that they appear in the universe. $\endgroup$ – Rob Jeffries Aug 12 at 16:32
  • $\begingroup$ Thanks @RobJeffries, will edit. BTW when then do they then "appear"? $\endgroup$ – niels nielsen Aug 12 at 17:35
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    $\begingroup$ @Ankit Pretty sure you don't need molecules (as evidenced by Helium gas having a temperature). Anything that emits blackbody radiation can be said to have a real temperature (as opposed to effective temperature). Failing that, just use the amount of energy and/or entropy present as an approximate indicator $\endgroup$ – Jim Aug 14 at 17:49
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The quarks were thought to be created from the potential energy of the decaying "inflaton" field at the end of the inflationary epoch. Any particles present prior to inflation would have become diluted to essentially zero number density by inflation. Indeed, this was one of the early motivations for the inflation theory - it successfully explained why we don't see exotic objects like magnetic monopoles, because their number density is extraordinarily low post-inflation.

At this point in time the weak force and electromagnetic force were unified and all the particles present (quarks, W, Z, gluons, photons, Higgs) were massless.

It was not until at around $10^{-12}$ s and electroweak symmetry breaking, that particles attained their masses via the Higgs mechanism and became the particles we know in the standard model.

At $10^{-12}$ s, the universe had a temperature roughly equivalent to the electroweak scale of 160 GeV. This energy scale sets roughly the maximum mass of particles that can be created at that time and indeed the top quark has a mass of around 170 GeV.

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  • $\begingroup$ Jefferies What does it mean that the particles were massless ?? $\endgroup$ – Ankit Aug 12 at 17:02
  • $\begingroup$ why didn't they gain more mass ?? Why were they restricted to their presently known mass ? $\endgroup$ – Ankit Aug 12 at 17:04
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    $\begingroup$ @Ankit particles get their mass via the Higgs mechanism. This took place along with electroweak symmetry breaking. Massless particles exist now - they are called photons. $\endgroup$ – Rob Jeffries Aug 12 at 17:38
  • $\begingroup$ Jefferies does the Higgs field give masses to a limited amount ?? Or why didn't the Higgs mechanism resulted in an extremely massive quark ?? $\endgroup$ – Ankit Aug 13 at 2:51
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    $\begingroup$ @ÁrpádSzendrei assuming particle number is conserved then particle number density is reduced to close to zero by inflation. $\endgroup$ – Rob Jeffries Aug 14 at 6:38

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