I've been reading about Bose-Einstein condensates, in which multiple bosons can occupy the same quantum state. I thought I understood how that could work until I learned that some atoms, such as Helium-4, are bosons.
It seemed to me that if two He-4 atoms H1 and H2 occupy the same quantum...
Whether traveling at c in the form of radiation and carrying energy in the process or to exert the force propagated by force fields, the mass-less gauge bosons cannot go faster than c and even the gravitational force which is caused by the space-time curvature or hypothetically gravitons cannot...
This is just an idea I had, but I can't seem to find any obvious flaws with it. It's pretty clear that the only description we have of fermions is as quantum objects. There is just no classical analog! Bosons however, have a very natural classical analog. If you just treat the quantum fields...
I'm working on a research project and was wondering what you could use to experimentally create a periodic infinite square well (dirac comb?) in a direction orthogonal to a different potential, say a periodic potential.
To help you understand what I'm trying to do picture a grid of atoms and...
Homework Statement
Suppose an ideal bose gas sees a periodic potential with a period a in both x and y directions. Its eigenstates are altered from the free-particle form. The lowest band has energies
\epsilon_\vec{k}=2t(2-cos(k_xa)-cos(k_ya))
where t is an energy scale that depends on the...
One says that bosons do not interact with one another. However, the presence of a gravitational field, and hence of gravitons (bosons) (assuming they exist), changes the probability of where a photon (boson) appears, which is the same sort of interaction as two fermions, no?
And, the contrary...
Homework Statement
Consider a system of N distinguishable particles which are distributed across levels with energies 0, 1, 2, 3, 4, 5... The total energy of the system is U. Determine all the possible combinations of the particles in this system and hence determine the total number of...
From here: http://blogs.scientificamerican.com/observations/2012/12/14/have-scientists-found-two-different-higgs-bosons/
So how significant would this be if it turns out to be true? I wasn't aware that there had been predictions of more than one Higgs in the first place, but the article says...
Homework Statement
Which of these particles don't follow Pauli exclusion principle and thus have a symmetric wave function?
a) Bosons
b) Fermions
c) Quarks
d) All particles follow Pauli exclusion principle
Homework Equations
None.
The Attempt at a Solution
I think that...
Quantum mechanics in 1 + 1 dimensions is equivalent to qft in 0 + 1 dimensions. This is because the position x(t) of a particle can be replaced by a scalar field \phi(t) , and the momentum is replaced by the momentum conjugate of \phi(t) .
Also, in the bosonic construction of heterotic...
Hello,
I was curious about how the exclusion principle applied to fermions and bosons differently. My current understanding is that the exclusion principle states that no two fermions may be in the same state of motion and that bosons do not obey the exclusion principle. My problem with this is...
My understanding is that for electrons, there is a standard argument that the electromagnetic interaction between them is required, not optional. Since they're identical particles, we should be able to take the wavefunction of two electrons and mix up their identities by any amount we like, and...
Can someone give me the names of all the particles that the standard model refers too
remember the first 18...
6 quarks (up- down,top-botoom,nice-paradox) x 3 colors = 18
and i also remeber the mpozons (photon,gluion,higgs,w and z ) :confused:
thank you
____________________
antonis...
why is that at relatively low temperature bosons can occupy the same state while the fermions cannot?
and how does we macroscopically see the effects of bosons (with explanations)?
a theoretical answer is preferable
I recall watching a documentary a while ago that explained the production of different force carriers. A bit that stuck in my head was that (if I remember correctly) W and Z bosons were able to violate the law of energy conservation. The energy to create these particles was apparently...
Hi
Could someone tell me if Higgs bosons exist in another dimension or if there's simply something i don't understand about their existence in our timespace?
Meaning - from what I understand - the recent experiments at the LHC smashed together particles with enough energy to create a Higgs...
The title says it all.
I've seen an example worked out, and there mass was given to a gauge boson specifically. Also, I wouldn't know why the Higgs boson would want to give mass to the fermions, since they already have mass in the Yang-Mills theories; it's only the gauge bosons that initially...
Dear Physics Forum,
I understand that forces between fermions are mediated by virtual bosons. My "sense"
of it is that a fermion produces virtual bosons (quarks would produce photons, gluons, and W/Z bosons; electrons photons and W/Z; neutrinos W/Z) within the confines of the uncertainty...
What are the charges of the X and Y boson?
I've been looking through online material, and most doesn't mention their charge. The only material I have found has been the Wikipedia page claiming to be +4/3 and +1/3.
This contradicts the only other sources I could find, saying that they are...
(If my question seems irrational, it's ok - I'm an undergrad!)
So I was reading up on the standard model and read that Z bosons are their own antiparticles. Does this mean that when two Z bosons are in physical contact, they annihilate? I ask this for photons too since I read this on the...
I'm wondering, is there still a sharp distinction between Bosons and Fermions in a rigorous QFT, if exsits?
My question is motivated by the following, consider one of the equations of motion of QED:
\partial_\nu F^{\nu \mu} = e \bar{\psi} \gamma^\mu \psi
In our familiar perturbative QED (Here...
It seems that no matter how far and wide I look, I can find no concise explanation as to the roles of bosons in a nuclear reaction, fusion and/or fission.
Thus, my inquiry: What role do bosons play in nuclear reactions, fusion and fission? What is the sequence of events that result in such a...
I understand how beta decay works on a fundamental level, in that either an up or down quark in the one of the nucleons decays into an up or down quark and in the process, a W boson is emitted which in turn decays into an electron and an electron antineutrino or opposites thereof depending on...
Hi,
If I have three light quark flavours with massses m_u, m_d,m_s , I want to try and calcuate the masses of the eight pseudogoldstone bosons.
I have found from my mass term in the Chiral L that:
L_{mass}=-2v^3...
I understand how the Pauli matrices can operate on the quantum state of an electron to obtain measurements of its intrinsic spin along the x, y and z axes. I also understand that since these matrices do not commute, it is impossible to determine what all three components were before measurment...
Why do the gluon and W and Z boson particles have a limited range of movement, 10-15m for the gluon and 10-18m for the W and Z bosons, when the photon particles, gravitational force, and other particles have no limit to the distance they can travel?
Please teach me this:
What is the origin of mass of both fermions and bosons?Is it correct that the origin is the spontanious broken symmetry of Higgs Field?(I know that Higgs mechanism is the origin of mass of vector boson W and Z in weak interaction).
Thank you very much for your kind helping.
Hello there,
I am looking at the decays of Heavy sterile neutrinos in the their mass states to Z bosons.
Using the feynman rules, how would I go about calculating the decay amplitude. I have only ever seen cases where the Z boson is a propagator. Would my expression look something like this...
Sorry for the newbie question. Just slap me and direct me to the right post. I did some searches but couldn't find my answer.
If a fundamental particle must exert one of the fundamental forces against another fundamental particle, are the appropriate gauges boson then created by the first...
The electroweak force is a unified force that combines both electromagnetism and the weak nuclear force. But since the electromagnetic force is mediated by photons and the weak nuclear force is mediated by W & Z bosons, which of these particles actually mediates the electroweak force? Is it the...
Z and W bosons have very short lives. I assume their decay is exothermic?
Is this true? I've seen various feynman diagrams showing how these particles decay, but I'm having trouble verifying that their decay is exothermic. Also, does either of their decay emit dangerous radiation, or is it...
Hi
In GSW theory we start with two fermions f f' (charge 0 -1) and 3 bosons w1 w2 w3.
the charge of the bosons in only introduced when one mix w1 and w2 giving w+ and w-.
Does it mean that before symmetry breaking f and f' were exchanging w+/w- but not
the basic w1 w2 w3?
What is meant by saying that the Goldstone-bosons are "eaten" by gauge bosons?
I've seen this statement all over, but can't find a good explanation of what this actually means. Anyone care to shed some light?
Hi,
I am interested in grand unification with extra dimensions. Especially the case when
extra dimensions are broken by orbifolding.
Now I am trying to understand how the Goldstonebosons appear in the spectrum of a
theory with global (for example SU(N)) symmetry. From the...
Can two Bosons 'collide' in the same sense as the Fermions (Since Pauli's exclusion principle is not applicable for Bosons)?
The Leptons have anti-leptons (positron, anti-muon, anti-tau and three anti-neutrinos). Each of the 6 Quarks have their corresponding anti-quark. So, do the gauge bosons...
How is it that the tendency for bosons to take the same state doesn't violate rules of entropy? I can understand why Bose-Einstein condensation wouldn't, because that's how the particles take a minimum energy state.
I know lasers work because the photons present encourage other photon...
The absorption or emission of W bosons changes neutrons to protons or protons to neutrons.Also,W bosons are almost 100 times as massive as the proton.The question is-How can a neutron emit a particle much more massive than itself and convert into a proton?
Are there Spin-2 bosons other than graviton? Does QFT allow for this?
Spin-1 bosons not only includes photons, but W Z bosons and gluons
could there be spin-2 bosons that have mass or have other types of charges?
It is well know that massless spin-1 gauge bosons have two spin states s³=+1 and s³=-1. There are two independent approaches how this can be shown:
1) via the representations of the Lorentz group for p²=0
2) via fixing / eliminating unphysical gauge d.o.f., e.g. via elimination of the...
Just wondering...
If the interactions between fermions are the emittance of a boson (from what I understand from the grand design book by stephen hawking) then when you punch someone, is it just high levels of bosons being emmited and clashing or are the actual boson particles colliding?
I am doing some research on Bose-Einstein condensates and was hoping someone could give me a non-mathematical reason as to why bosons 'want' to occupy the same ground state. I think its details come from Bose-statistics, but is there a simplified way of explaining it? Thanks
Homework Statement
calculate the possible number of ways of distributing 2 particles among four energy startes when:
particle are distinguishable and there is no restriction on the occupancy of the energy state
Homework Equations
\frac{(n+g-1)}{n!(g-1)!}
The Attempt at a...
Hello, if someone could enlighten me I'd be most grateful.
Also, if anybody could point me in the direction of some really good free resources that would be great too. Thanks.