Questions tagged [bosons]
Bosons are integer-spin particles that obey Bose-Einstein statistics. Two bosons can occupy the same quantum state.
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Can not follow derivation of WZ(0, 0) amplitude in paper
i am re-reading this paper and trying to follow the derivation of equation (21) from equation (15).
Maybe someone can tell me where i am going wrong.
So the original equation 15 is:
$$M(0,0) = F\frac{\...
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What's happening in this approximation for the equation of state of an ideal gas of bosons
The way we arrived at the equation of state for an ideal fermion gas was to approximate the right handside of $$\beta PV=\sum_{\vec{p}}\log{(1+fe^{-\beta\frac{p^2}{2m}})}$$
as $$\frac{V}{h^3}\int \log{...
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Fourier transform of the Heisenberg antiferromagnetic model
I have a short question about the Fourier transform of the antiferromagnetic Heisenberg model.
The Hamiltonian, written in terms of bosonic operators, is:
$$ \widehat{H} = -NJ\hbar^2s^2 + J\hbar^2s \...
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Does the completeness relation for vector bosons hold also in this form?
Consider a generic Spin-1 vector field (massless) $A^{\mu}$, we know that the solution for its equations of motion can be built as
$$A^{\mu}(x)=∫ d^{3}kN_{k}(\epsilon^{\mu}(\stackrel{\rightarrow}{k},\...
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Confusion about spin in 1 dimension
If spin should not be defined for particles in 1 dimension since we can't do rotations in 1d, like it happens for the orbital angular momentum, then why can we talk about fermions in a 1 dimensional ...
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Mermin-Wagner theorem and SSB in 2D: is there sound in low dimensional solids
The Mermin-Wagner theorem states that there cannot be any spontaneous symmetry breaking happening in systems with short range interactions below dimension 3. Moreover, we know that Goldstone boson, ...
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Why do we only consider commutators and anticommutators in QFT?
While studying canonical quantization in QFT, I observed that we quantize fields either by a commutation or an anticommutation relation
\begin{equation}
[\phi(x), \phi(y)]_\pm := \phi(x) \phi(y) \pm \...
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WZW primary fields / correlations in terms of current algebra?
Cross-posted from a Mathoverflow thread! Answer there for a bounty ;)
Given the
$\mathfrak{u}_N$ algebra
with generators $L^a$ and commutation relations
$ [L^a,L^b] = \sum_c f^{a,b}_{c} L^c $ ,
the ...
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Is it possible to construct theory where fermions are force carriers?
Supersymmetry is a model based on symmetry between bosons and fermions. Bosons carry force and they are described by potentials. Fermions are matter particle and they are described by wavefunctions. ...
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What mathematics indicate that the vacuum of the universe is metastable?
As I understand it, the meta stability of the universe's vacuum depends on the electroweak force, which depends on the mass of the top quark and the Higgs boson. But I don't understand this fully. Can ...
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Can the Keldysh occupation function have a zero for bosons or a pole for fermions?
In the Keldysh framework for nonequilibrium dynamics of quantum systems we learn that there are essentially two Green's functions that characterize a system: the retarded Green's function $G^R(\omega)$...
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Changes due to Chargeless Bosons
Do chargeless bosons (i.e. Z boson and photon) change any properties in particles they interact with besides energy, momentum, and angular momentum/spin?
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Diffuse boundary condition for fermigas/bosongas
I'm doing math, usually working only in the classical framework, but my background in quantum physics is close to zero so please forgive me if the question does not make sense.
I was looking into ...
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Is it theoretically possible to get a fermion fields from compactifying a bosonic field theory?
It doesn't seem impossible to me that compactifying a purely bosonic field theory could result in spinor fields.
For example, the spin groups (the double covers of $O(n)$) have representations in $2^{...
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ELi5- How do pions hold nuclei together if they are so short-lived?
I need help understanding how particles do what they do and maintain the structures they maintain if so many of them exist for such a short time?
In the case of the nucleus and pions, pions only exist ...
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Quantum vs Classical solution to the Gibbs Paradox [duplicate]
The thermodynamic probability of a gas
with distinguishable particles having spin-$0$ is given by the expression:-
$Ω_{MB} = N!~Π_i\frac{g_i^{n_i}}{n_i!}$
If the particles were indistinguishable, the ...
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Bosonic Gas vs Ideal Gas
Bosonic Gases and Ideal Gases have these properties in common:
They are composed of
indistinguishable particles.
The particles of both gases do not
obey the Pauli Exclusion
Principle.
As far as I ...
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Does the Pauli exclusion principle apply to mesons?
According to the Pauli exclusion principle, two identical fermions cannot occupy the same quantum state simultaneously, but two bosons can. Mesons are bosons, but composed of two quarks, and quarks in ...
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If the bosons in a certain interaction can be outside of their mass hyperbola, how can we know the mass of the particles?
As far as I know, the virtual particles that appear in Feynman diagrams are allowed to be outside of their mass hyperbola, namely
\begin{equation}
k^2 = \omega^2 - (\vec{p})^2 = m^2
\end{equation}
So ...
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Why not use Bose-Einstein Statistics to derive the Planck's blackbody radiation law?
While deriving the Planck's radiation formula, why do we use MB statistics when we calculate the average energy of oscillators? Shouldn't we use BE?
Is this because temperatures concerned are very ...
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Has it been verified experimentally that the $Z$ boson interact with gravity?
Does the $Z$ boson interact with gravity? I understand it has a measurable mass. I'm instead looking for an experiment that says, unequivocally, it interacts with gravity (as opposed to, e.g., having ...
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Why doesn't the Pauli exclusion principle apply to bosons?
Everything I've read online seems to say/imply that the Pauli exclusions principle only applies to fermions and not bosons.
As I understand it the Pauli exclusion principle arises when the spatial ...
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Does the ground state of interacting of interacting spinless/scalar bosons in a centrally symmetric potential have angular momentum 0? [duplicate]
Motivated by this question: If electrons were spinless/scalar bosons, would atomic ground state configurations necessarily have total orbital angular momentum zero?.
Can we make a group-theoretical ...
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Were all particles once bosons?
For all matter to have been occupying the same point in space, this would violate the Pauli exclusion principle. Since fermions cannot occupy the same quantum state, the particles that are now ...
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Bosonic excitation investigated by scattering experiments in condensed matter physics
Why experimental tools like Raman scattering, Inelastic neutron scattering (INS), Resonant inelastic X-ray scattering (RIXS), etc., can only detect bosonic excitation?
Why electronic excitation won't ...
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Why are interactions mediated by the $W$ bosons and the $Z$ bosons classified as a single type of force when they are so different?
We always hear of 4 Forces or interactions, i.e. the Strong Force, Electromagnetic Force, Weak Force and Gravity. Each force has its mediating Bosons, i.e. gluons for Strong Force, photons for ...
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Microstates in a quantum gas and the occupation number
The occupation number of a gas of fermions or bosons is typically defined as:
$$\bar{n} = \sum_n n\ p_n$$
where n is the number of particles in each state.
But $n$ is just a number of fermions (or ...
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What force could theoretically redirect the Higgs field? [duplicate]
I’d just like to point out I am by no means a physics expert, or indeed a particularly knowledgable nerd on this subject. I am a minor and a wannabe sci-fi writer who is trying to come up with an idea ...
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How are Bosons force-carriers?
In QFT, the exchange of Bosons between certain particles is responsible for the effect of force. My question is how can exchanging bosons lead to a force. Is force defined differently in QFT? (Aka. ...
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Why are some collections of fermions considered bosons?
I read that He-4 is a boson because the four fermions in it add up to an integer spin—of zero—hence a boson.
Whereas I thought that if the parts are fermions, so is the whole.
Is an electron pair a ...
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How to update $SU(2)$ Higgs fields with Heat Bath algorithm?
I'm trying to update the Higgs field coupled with a pure gauge $SU(2)$ theory through Heat Bath algorithm. Pure gauge and Higgs configurations should be updated separately. For the pure gauge part the ...
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What happens to spin when bosons exchange bosons?
I understand that spin is a conserved quantity, I also understand that gluons can exchange gluons, and $W$ bosons exchange photons. However, when I try to combine these concepts, I can't figure out ...
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Commutation relations for fermionic and bosonic creation and annihilation operators [duplicate]
I'm trying to calculate commutator:
$$ [a_{k}^{\dagger}a_k,a_{k'}^{\dagger}a_{k'+q}b_q^{\dagger}]_{\_} $$
where $a_k$, $a_k^{\dagger}$ - annihilation and creation operators for fermions, $b_q^{\dagger}...
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How to couple the Higgs field with $SU(3)$ (and/or $SU(2)$) Yang-Mills theory in numerical simulations?
I'm trying to couple the Higgs field to numerical simulations of pure gauge theory with heatbath and overrelaxation update of link variables. I don't know how to insert the Higgs field into the ...
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Why is $W$ boson decay into more than 2 particles not possible?
I am studying hadronic decay of the $W^-$ boson. I am aware that the decay into quarks from different generations is not possible and that charge as well as the total angular momentum have to be ...
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What forces might the bosonic superpartners of the fermions of the SM mediate?
If the models of the universe that posit the existence of fermionic superpartners to the bosons, and bosonic superpartners to the fermions are correct, then what forces would be mediated by the ...
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Struggling to understand Identical particles
I'm struggling with the concept of identical particles in QM. Say I have two electrons, with one trapped on my left $\left|\uparrow\right\rangle_1$ and one trapped on my right $\left|\downarrow\right\...
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Can a graviton be a spin-2 particle made from 2 spin-1 particles?
Presumably there would be a force holding the 2 spin-1 particles together.
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Left hand side of Debye Model 2d
I'm studying Debye model and I realized that I don't know what the left side means, specially why there's a $3$.
For the 2 dimensional model we have $$\sum_{modes} 3 = 3N$$
$N$ could be the atoms and $...
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Which particles do $W$ bosons interact with to gain mass?
Which particles interact with $W$ bosons to give them mass?
I am aware that Higgs particles alone are not responsible for the mass of other particles.
In non-mathematical terms which particles give ...
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Why is the degeneracy factor for Bose Einstein distribution set to 1 automatically?
In https://scholar.harvard.edu/files/schwartz/files/12-bec.pdf, the article says
"With Bose-Einstein statistics, we determined that using the grand canonical ensemble the expected number of ...
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Can a neutrino emit a $W^+$ boson?
In the reaction $\nu_e + p \rightarrow e^-+ \Delta^{++}$, a Feynman diagram would be:
So my question is, could a neutrino emit that $W^+$ boson (knowing that the boson's mass is much higher than the ...
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Why, conceptually, are identical bosons "pulled together" and identical fermions "pushed away"?
I have seen the calculation for the separation distance of indistinguishable particles versus distinguishable ones. According to Griffiths (Pg. 204 3rd Ed.), the difference in separation distance is $$...
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Have the $W_0$, $W_1$, $W_2$ and $B$ bosons of Electroweak fame ever been discovered experimentally?
I have read that the LHC, and perhaps other collides, have reached so-called electroweak energies, where the two forces are unified....
So how much energy, exactly, is needed to produce fields/...
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Has the $N$-representability problem for bosons been solved?
The $N$-representability problem in non-relativistic quantum mechanics is the question whether a 1- or 2-particle mixed state is a reduced density matrix of a pure $N$-particle wavefunction. Has this ...
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Axial and vectorial couplings of fermion
From some of the review papers that i read, there is a phrase, Dirac fermions have just vectorial couplings to the $Z'_{B-L}$ boson.
Good day, what does axial coupling and vectorial coupling means? ...
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How does sodium-23 manage to form a Bose Einstein condensate with 11 protons and 11 electrons?
As asked in How is a Bose-Einstein condensate produced from sodium atoms that do not have an integer spin? , Sodium 23 has been used experimentally to form a Bose Einstein condensate.
Sodium 23 is the ...
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Are there practical applications for boson sampling?
Boson sampling is a computation that is not doable on classical machines but quite doable on quantum photonic machines.
(https://www.researchgate.net/figure/Experimental-results-for-3-and-4-boson-...
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Quantum Mapping of a Generalized 2D XY Model
I have been reading this paper, which discusses the deconfinement transition in the 2D generalized XY model. The classical Hamiltonian is given by the following. See page 2 of the paper.
$$
H = - J\...
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How could have Boson Stars formed in the universe at all?
Boson particles have been predicted by some to have been able to form stars known as Boson Stars. I am curious as to how these stars could have formed given that Boson particles are not truly affected ...
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