Questions tagged [quark-gluon-plasma]
A state of matter in which quarks and gluons are freed of their strong attraction for one another under extremely high energy densities.
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Which hadrons were present after the phase transition from the post-Big Bang QGP?
This question relates to the "hadron epoch" (after the initial quark-gluon plasma, but before the end of baryogenesis).
My understanding is that the phase transition that ends the quark-...
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Green's function for a 0+1 D wave equation in Milne coodinates
Consider a system in $3+1$ D Minkowski space with coordinates
$\tau,r,\theta,\eta$, $g^{\mu\nu} = (1,-1,-r^2,-\tau^2)$ with a metic given by
\begin{equation}
{
ds^2 = d\tau^2-dr^2 - r^2d\theta^2 - \...
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Matter-antimatter asymmetry during hadronization
When quark gluon plasma is created during heavy ion collisions, the QGP exists extremely briefly before hadronizing--the process where the QGP cools and quarks combine to form colorless hadrons. A ...
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Can the quark-gluon plasma of the very early universe be accurately characterized as a type of quark star?
The very early universe was dense and opaque. During the quark epoch, the entirety of the universe, up to every boundary, was a filled-in ball of QGP. Much like a star is a ball of ionized nuclei that ...
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Detection of quarks, gluons and color charges in quark-gluon plasma?
Due to quark confinement and color charge neutrality, individual quarks and gluons are non-observable under ordinary circumstances.
However, under extreme temperature achieved by colliding Pb+Pb ...
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Could there be a hybrid particle made of one quark and one or several gluons?
The question's background is that such a quark-gluon bound state
might be colour-less.
But it seems that no such particle is ever mentioned.
Is there a reason speaking against its existence?
ADDED:
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Do the different generations of fermions correspond with the epochs of the very early universe?
Up and down quarks as well as electrons and electron neutrinos currently dominate. Is it possible, that during the electroweak epoch, charm and strange quarks dominated? and that during the gut epoch, ...
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Can an electroweak plasma exist at room temperature?
Above around 246 GeV ($10^{15}$ Kelvin), the weak and electromagnetic forces are thought to be merged. See Electroweak interaction. This is thought to occur in the cores of over dense neutron stars ...
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Can free quarks exist?
I know that currently free quarks do not exist but can they exist under any circumstance? The Physicsworld article Quarks break free at two trillion degrees states that they do but I want a ...
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What particles existed in the Planck, GUT, and electroweak epochs, respectively?
What quarks, leptons, and bosons existed in each of the individual epochs of the early universe (Planck, GUT, electroweak)? Did the quantum zoo gain or lose species during these times? Or did some of ...
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Why does Pseudorapidity distribution have two peaks?
I found plots(fig2) that state that it is the sum of two gaussian distributions, but I am not able to understand its physical significance. Any help would be appreciated.[PS Why does rapidity not have ...
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Why did the quark epoch occur earlier than the lepton epoch?
I don't understand the reason and hypothesis behind why the quarks appeared first—as per the big bang cosmology—shortly after the strong and electroweak force separated. We don't know what the quarks ...
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Could charm, bottom, and even top matter form under the right circumstances?
Strange matter forms because turning some of the down quarks into strange quarks unlocks lower energy levels, and this can lower the system's overall energy at high densities. If the density was ...
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Is quark-quark interaction possible under extreme heat and pressure circumstances?
The neutron-rich core of neutron stars, underneath extreme pressure and heat, undergoes a phase transition to quark-gluon plasma. If both heat and pressure are increased to exceed beyond the TOV limit,...
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How exactly does the quark gluon plasma prevent protons from forming?
I have read this question:
The difference is that the quark-gluon plasma is governed by the dynamics of the strong interaction, which isn't very well understood, so that's what people are interested ...
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Color-magnetic fields in quark-gluon plasma?
I was curious as to whether there is a color equivalent of magnetic field in CCD. The answers here suggest there is, but only at femtometre scales due to confinement. Is this the case also for the ...
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If singular Quarks cannot exist on their own, then how is Quark-Gluon Plasma possible?
To my understanding, QGP is a theoretical form of matter where quarks are freely floating around. I understand immense temperature and pressure is required to form this. Also to my knowledge, quarks ...
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Why we multiply the quark contribution term by 7/8 while calculating the degrees of freedom for QGP?
Why we multiply the quark contribution term by 7/8 while calculating the degrees of freedom for two flavour QGP?
That is,
g = 7/8 (2×2×2×3) + 2 × 8
Why there is a factor factor of 7/8 ?
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What’s the basic procedure to draw a QCD phase diagram?
Could someone recommend a book/resource where I can find a detailed way of sketching out a QCD temperature-chemical potential phase diagram using gap equations (eg. equations 35-37 or 39-40 as given ...
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Why is strangeness enhanced in quark-gluon plasma?
How does the observation of strangeness enhancement in high-multiplicity proton–proton collisions explain the existence of quark-gluon plasma?
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What is Hagedorn Temperature?
I would like to get an understanding of the value of the Hagedorn temperature and the units this temperature can be given in. Is the Hagedorn temperature the maximum temperature, just as $0\ K$ is the ...
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Why photon do not interact in quark gluon plasma?
It is often said that we could probe quark gluon plasma with photon or dileptons, because they interact electromagnetically so tha tthey don't modify the medium.
But do they do not modify the medium ?...
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What is the link between the energies of particles and the corresponding temperature, in context of quark gluon plasma?
What is the link between the energies of particles and the corresponding temperature, in context of quark gluon plasma ?
Is quark gluon plasma existing at low or high energy of particles ? Or is it ...
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Quark gluon plasma at arbitrarily high temperature
Does the quark-gluon plasma become weakly coupled at infinite temperature (due to asymptotic freedom), or does it maintain some non-perturbative behavior?
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Which equations of QCD are the QGP (Quark Gluon Plasma) and QCD phase diagram coming from? [closed]
Which equations of QCD are the QGP (Quark Gluon Plasma) and QCD phase diagram coming from ?
Are there derivation formulas ?
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What do you mean by quark gluon plasma is frictionless?
I read about the similarities between quark gluon plasma and Bose Einstein condensate especially both are frictionless, I know generally when everday object rubs against one another the electrons get ...
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Is there some truth to the "vacuum as bubbling soup" story?
There are many discussions on this site about the nature and reality of vacuum fluctuations. The general consensus seems to be that this it falls into the Lie-to-Laymen category. On the other hand, ...
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How would a quark star maintain degeneracy near the surface?
I'm still not exactly understanding how a quark star could possibly exist for more than a fraction of a second. Neutron stars are already hypothesized to have degenerate quark matter at their cores, ...
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Why is color screening in Quark Gluon Plasma not effective for light quarks mesons like pions?
The color screening of quarkonia states like $J/\psi$ (bound states of charm and anti-charm) and $\Upsilon$ (bound states of beauty and anti-beauty) is considered one signal of QGP (quark-gluon plasma)...
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Do Quarks decay into Photons at high enough temperatures?
At high enough energy, particles lose coherence and are ripped apart into a Quark-gluon plasma where the individual quarks can break free of the atomic nucleus and fly around unencumbered.
A black ...
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Detecting the electroweak unification in data of quark gluon plasma
Electroweak unification is discussed in the Big Bang model and variant proposals, and there is a transition at energies of 100 GeV where the EW symmetry is unbroken and a quark gluon plasma phase ...
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If quarks can't be isolated in the first place, how did they become confined in the early universe?
On one hand, we know that quarks cannot exist in isolation. This is because the energy required to dissociate a quark-antiquark pair in a meson (or quarks in a hadron) will create a mesons (or hadrons)...
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s-wave radial equation for minimally coupled scalar field
I am trying to work through the calculations from the following article.
I need to find the s-wave radial wave equation for a minimally coupled scalar field, given by $\partial_{\mu}( \sqrt {-g} g^{\...
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When/ how were/are quarks formed?
We know that all particles can eventually be converted into energy. We know also that electrons were and still are formed by pair production from a 1MeV photon.
Do physicists have yet any idea how ...
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Bag model and MFT
Can I think of the MIT Bag model as an application of mean field theory (MFT) in nthe domain of nuclear physics? All the interactions between quarks are mediated via strong interaction, whose exact ...
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Is it sensible to talk about protons at the time when the universe was a quark-gluon plasma?
I'm currently studying from "Particle Astrophysics" by Perkins.
On page 132 it says:
After $kT$ fell below the strong quantum
chromodynamics (QCD) scale parameter ∼ $200$ MeV, the remaining ...
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Hadron contribution to effective degrees of freedom in early Universe
In transition from quark-gluon plasma to hadron gas in the early Universe, the value of the effective degrees of freedom $g_{\star}$ decreases abruptly. This seems to me like a sort of decoupling: ...
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Can nuclei ever "liquify"?
I've been reading about degenerate matter and how extreme temperatures and pressures can impact the way it organizes itself. Plasma is a type of matter where the energy of the matter allows electrons ...
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Are bottomonium and charmonium the only quarkonium systems?
I had a question:
Are bottomonium and charmonium the only quarkonium systems?
I was searching the internet and found that these two systems have been experimetally observed but the toponium has ...
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Are perturbative and non-perturbative QCD both signs of new physics?
I was studying about quarkonia systems and reached this page at CERN Courier. Here, I came across the following text:
While the failure to reproduce an experimental observable that is ...
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Where did all the negative potential energy in gluons went to?
I have watched PBS Space Time that gluons could be viewed as negative potential energy (tension between quarks) and that they actually are 99% of all the mass in protons and neutrons.
Now the way I ...
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Strong force equivalent of electricity?
Could colour charges be manipulated into something analogous to the flow of electricity, and if so, would there be any situation in which circuits of this kind would be useful? For example, given a ...
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Doubts about quark confinement, the pole mass and the quark gluon plasma
I have seen written a few times that the notion of a pole mass for a quark contradicts the quark confinement picture and that non-perturbatively it is expected that the quark pole mass be infinite. ...
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Is it possible to create a quark-gluonic reactor to produce energy with help of strong interaction?
Is it possible to create a quark-gluonic reactor to produce energy with help of strong interaction? Can it be done with quark-gluon plasma?
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plasma frequency in terms of thermal energy
The relativistic factor (in terms of momentum) is given by
\begin{equation}\label{}
\gamma=1/\sqrt{1-v^{2}/c^{2}}=\sqrt{1+p^{2}/m^{2}_{0}c^{2}},
\end{equation}
When thermal momentum is greater ...
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Fluctuating string in AdS black hole
People frequently use fluctuating string in AdS black hole (see 1,2,3 etc) to study dynamics of a "free external quark" in quark-gluon-plasma (QGP) at finite temperature. The background black hole ...
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What flavour is quark gluon plasma?
What flavour of quarks make up quark gluon plasma? What would it most likely cool down into, protons, neutrons, strange matter, neutronium or what?
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What are non-Abelian plasmas?
I know what a non-Abelian group is: a group whose operation does not obey commutativity. Does this have anything to do with a non-Abelian plasma? I'm not really looking at a specific paper, but I'll ...
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Extreme temperatures, relativity and kinetic theory
According to kinetic theory, average kinetic energy is proportional to temperature. Supposing $k_BT/2$ per particle, can we use relativity and kinetic theory to calculate, e.g., the temperature and ...
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Reference on stages of heavy ion collisions in particle physics
Is there any reference (book/review article etc.) where the physics of heavy ion collisions is overviewed?
To be absolutely clear about things, I am looking for a introductory review which covers ...