Content deleted Content added
Johnjbarton (talk | contribs) →Beyond the Standard Model: consequences |
Johnjbarton (talk | contribs) →Strong force phase transition: move figure up to the paragraph it illustrates |
||
Line 25:
===Strong force phase transition===
The strong force binds together [[quarks]] into [[protons]] and [[neutrons]], in a phenomenon known as [[color confinement]]. However, at sufficiently high temperatures, protons and neutrons disassociate into free quarks. The strong force phase transition marks the end of the [[quark epoch]]. Studies of this transition based on [[lattice QCD]] have demonstrated that it would have taken place at a temperature of approximately 155 [[MeV]], and would have been a smooth crossover transition.<ref name="aoki-qcd">{{cite journal |last1=Aoki |first1=Y. |last2=Endrodi |first2=G. |last3=Fodor |first3=Z. |last4=Katz |first4=S. D. |last5=Szabo |first5=K. K. |title=The order of the quantum chromodynamics transition predicted by the standard model of particle physics |journal=Nature |date=2006 |volume=443 |issue=7112 |pages=675–678 |doi=10.1038/nature05120|pmid=17035999 |arxiv=hep-lat/0611014 |bibcode=2006Natur.443..675A |s2cid=261693972 }}</ref> In the early universe the chemical potential of baryons is assumed to be near zero and the transition near 170MeV converts a quark-gluon plasma to a hadron gas.<ref name=Manzudar-2019/>{{rp|25}}▼
[[File:QCD phase diagram.png|thumb|300px|right|Conjectured form of the phase diagram of QCD matter, with temperature on the vertical axis and quark [[chemical potential]] on the horizontal axis, both in mega-[[electron volt]]s.<ref name='RMP'/>]]
▲The strong force binds together [[quarks]] into [[protons]] and [[neutrons]], in a phenomenon known as [[color confinement]]. However, at sufficiently high temperatures, protons and neutrons disassociate into free quarks. The strong force phase transition marks the end of the [[quark epoch]]. Studies of this transition based on [[lattice QCD]] have demonstrated that it would have taken place at a temperature of approximately 155 [[MeV]], and would have been a smooth crossover transition.<ref name="aoki-qcd">{{cite journal |last1=Aoki |first1=Y. |last2=Endrodi |first2=G. |last3=Fodor |first3=Z. |last4=Katz |first4=S. D. |last5=Szabo |first5=K. K. |title=The order of the quantum chromodynamics transition predicted by the standard model of particle physics |journal=Nature |date=2006 |volume=443 |issue=7112 |pages=675–678 |doi=10.1038/nature05120|pmid=17035999 |arxiv=hep-lat/0611014 |bibcode=2006Natur.443..675A |s2cid=261693972 }}</ref> In the early universe the chemical potential of baryons is assumed to be near zero and the transition near 170MeV converts a quark-gluon plasma to a hadron gas.<ref name=Manzudar-2019/>{{rp|25}}
This conclusion assumes the simplest scenario at the time of the transition, and first- or second-order transitions are possible in the presence of a quark, baryon or neutrino [[chemical potential]], or strong magnetic fields.<ref name="Boeckel2011">{{cite journal |last1=Boeckel |first1=Tillman |last2=Schettler |first2=Simon |last3=Schaffner-Bielich |first3=Jurgen |title=The Cosmological QCD Phase Transition Revisited |journal=Prog. Part. Nucl. Phys. |date=2011 |volume=66 |issue=2 |pages=266–270 |doi=10.1016/j.ppnp.2011.01.017|arxiv=1012.3342|bibcode=2011PrPNP..66..266B |s2cid=118745752 }}</ref><ref name="Schwarz2009">{{cite journal |last1=Schwarz |first1=Dominik J. |last2=Stuke |first2=Maik |title=Lepton asymmetry and the cosmic QCD transition |journal=JCAP |date=2009 |volume=2009 |issue=11 |pages=025 |doi=10.1088/1475-7516/2009/11/025|arxiv=0906.3434|bibcode=2009JCAP...11..025S |s2cid=250761613 }}</ref><ref name="Cao2023">{{cite journal |last1=Cao |first1=Gaoging |title=First-order QCD transition in a primordial magnetic field |journal=Phys. Rev. D |date=2023 |volume=107 |issue=1 |pages=014021 |doi=10.1103/PhysRevD.107.014021|arxiv=2210.09794
| |||