Bosons Definition and 215 Threads

If my understanding is correct, all particles are sources of gravitational fields (albeit minor ones), and the gravitational potential energy between two bodies is given by: U = -GMm/r So, if we have two Z bosons (or any other bosons with mass but no repulsion due to charge) which are traveling...

On page 9 of *Quantum theory of many-particle systems* by Alexander L. Fetter and John Dirk Walecka, during the derivation of the second-quantised kinetic term, there is an equality equation below: >\begin{align} \sum_{k=1}^{N} \sum_{W} & \langle E_k|T|W\rangle C(E_1, ..., E_{k-1}, W...

Hi, is correct to say that there is no interaction between four photons because the gauge group of QED is U (1) while there are interactions of four gluons or four W's because the gauge group of QCD is SU (3) and EW's one is SU (2) xU (1)? I know that the interaction between four photons is not...

Homework Statement In 2012, the LHC ran with peak luminosity ##7.73\times 10^33## and at c.o.m. energy at 8TeV. The Higgs can be produced by a number of processes including ##\sigma_{ggf} = 19.0 \pm 7.5##pb and ##\sigma_{VBF}=1.6 \pm 0.3##pb. In 2011 a total integrated luminosity of...

MSSM and nMSSM require 5 higgs like bosons in addition to the 126 GEV the SM predicts. thus far LHC has not found any of them. what masses are predicted for Natural SUSY for these additional higgs and how much of a problem is it that the LHC has not found them? if natural SUSY is correct...

In quantum potential concept in Bohmian mechanics or others where the wave function exist ontologically, do they have their corresponding field and bosons (since the wave function is real hence should act like a field like the Higgs field or electromagnetic, strong field?) The answer seems to...

I am relatively well versed when it comes to systems of spin, or doing the maths for them at least, but am unsure whether all of the {L2, Lz, (other required quantum numbers)} basis eigenstates for a general system of n particles of spins si, where si is the spin of the ith particle, can...

Will all particles be in excited state in boson condensate if temperature approach infinity?

How come gravity and electromagnetism have an infinite range, while the strong nuclear force dies out quickly? I understand that the weak force's bosons, the W+, W- and Z (neutral), have relatively large mass, and decay quickly, while the photon and the graviton (theoretical carrier of gravity)...

Hey! I'm studying some particle physics. I ran into this example of a gluon decaying into a u - anti-u pair. (According to example 9: http://teachers.web.cern.ch/teachers/archiv/HST2002/feynman/examples.htm) How come this happens via strong force. Why isn't a Z0 boson doing this instead? Thanks!

About 40 years ago, someone told me that free neutrons decay with a half life of around 14 minutes. About 10 years ago, I discovered that W bosons were involved, and that they are about 100 times as massive as a proton. Do W bosons really exist as "massive" particles for their very brief...

An interesting article, but what does it mean to the electronics industry?https://www.sciencedaily.com/releases/2016/03/160314111135.htm Date: March 14, 2016 Source: University of Cincinnati Summary: Theoretical physicists are about to report on a controversial discovery that they say...

Like, for example, how do photons attract positively and negatively charged particles. I need some help visualizing it.

I'm somewhat familiar with the General Relativity description of gravity, at least conceptually. So I thought I'd ask about the graviton theory of gravity. Specifically, I've read elsewhere that a graviton must be a Spin-2 boson. Okay, given that as it may, how does a spin-2 boson differ from a...

When my eighth grade daughter was studying physics in her class, I watched a movie with her on the Hadron Collider (" Particle Fever "). We discussed atoms, electrons, protons, neutrons; we discussed orbits and statistics, and then down into the standard model and fermions, leptons, yadda...

I most recently heard about the new mathematics that help predict glueballs properties better. I had the really strange question of, why can't all other bosons have a cluster particle, like the glueball. Is it due to there force strength over distance or am I missing something.

if we have two particle then how we differentiate between boson and fermion ,any experiment that differentiate them?

Buried in a recent talk by John Ellis, the following passage: Reference 92 is Weinberg & Witten 1980, reference 93 is a talk by Zohar Komargodski at the same meeting.

<<Mentor note: Moved from other thread.>> I have 4 questions: 1. Why Weinberg angle affects neutral boson mixing, while W+ and W- are unaffected? 2. Is there any relation between Weinberg angle and CP violation angle? Are they absolutely independent? 3. How our world would be different if...

From a recent thread: Is this true of gluons? Doesn't the color charge invert under CPT? (For example, a red-antigreen gluon's antiparticle would be a green-antired antigluon.)

In one book of Susskind I found the following claim and I wanted to ask for its basis. Susskind says that each kind of boson gives positive contribution to the cosmological constant (the lighter, the better). Each kind of fermion gives negative contribution to the cosmological constant. Thus...

This is as far as I've got so far but I think I'm stuck. These bosons are inside neutrinos and they go near the speed of light. The half life of these bosons (lambada) is 3*(10-25) s The speed of light (c) is 299 792 458m/s So I did this c / 3*(10-25) = 9.993081931m/s I just don't have a good...

Hi, so my question is along the lines of the following: Since the strong and EM forces are mediated by massless exchange particles, due to Heisenbergs uncertainty principle these forces are long range. Well, ok. But the weak force is mediated by W and Z bosons which are massive hence they can...

I am confused about how the gauge boson W+ and W- get their charge under spontaneous symmetry breaking in the Higgs mechanism. Here's what I have so far: The covariant derivative for a SU(2)⊗U(1) is DμΦ = (∂μ + igWμiσi/2 + ig'Bμ)Φ where g and g' are coupling constants. SU(2) is associated...

Why is it not possible for a particle to be neither symmetric nor antisymetric on exchange? If a particle can have 1/2 integer spin why can't it have 1/3 , 1/4 etc. I know it's a weird question to ask but I've been wondering about it for a while.

I have now seen it repeated multiple times that a particle (a fermion, perhaps?) moving in a condensate can exchange particles (bosons, most probably) "without effect" -- the version of this that I run into usually goes something like that the energy of the condensate does not change AT ALL...

For a system consisting of multiple components, say, a spin chain consisting ofN≥3spins, people sometimes use the so-called geometric measure of entanglement. It is related to the inner product between the wave function and a simple tensor product wave function. But it seems that none used this...

Is there any significance to the fact that: The electromagnetic and strong interactions have gauge bosons with no electric charge that are massless; and The weak interaction has two massive gauge bosons which do have electric charge. If there is a significance to this 'observation' then where...

1. Homework Statement The question is to determine which decays are possible for: i) ##P^0 ->\prod^+ \prod^-## ii)##P^0 ->\prod^0 \prod^0## Homework Equations where ##J^p = 0^-, 1^- ## respectively for ##\prod^+, \prod^- , \prod^0## and ##P^0## respectively. The Attempt at a Solution For...

In most introductory QFT treatments, it's stated early on (and without proof) that particles with even integral spin are always attractive, while those with odd integral spin can be repulsive; sometimes this is even cited as evidence that the graviton must be spin 2 (I think Feynman's...

I've seen explanations that when a neutrino with a W+ Boson comes near a neutron, it affects one of the bottom quarks and changes it to a up quark which effectively turns the neutron into a proton. The neutrino then turns into an electron. Source: (2:20 onwards) I've seen other explanations...

I'm a little confused. During Beta(-) radiation, a neutron becomes a proton due to a down quark becoming an up quark. When this happens, a W(-) boson is emitted which almost immediately decays into an electron and an electron antineutrino. A W(+) boson, similarly, is emitted when a down quark...

If the Higgs boson is an excitation in the Higgs field, does that mean that it is exceedingly rare? Do they exist only on earth, or are they also created in high energy places such as quasars? Are the number of Higgs bosons that have existed in the universe on the order of hundreds, billions, or...

Hi all, I wonder if I study new Higgs scalars, How the data of the LHC for searching for heavier scalars in h-> WW->lvlv and h -> ZZ-> 4 l channels like in [arXiv:1304.0213] can make constrain on my study for the new Higgs? How a figure like figure 2 can give constrains on my model free...

Hi PF. If I have two identical bosons, one in the single-particle state \phi_{a}(x) and the other in the single-particle state \phi_{b}(x), the two-particle state of the system would then be : \psi(x_{1},x_{2}) = \frac{1}{\sqrt{2}}\big(\phi_{a}(x_{1})\phi_{b}(x_{2}) +...

Three Bosons: the Photon, the Gluon, and the Graviton are all massless Bosons; they all travel at the speed of light and therefore have no interaction with the Higgs field. How is it possible to differentiate between these three particles being that the Photon is a Majorana Fermion and therefore...

Since everything is energy, can fermions and bosons be (theoretically) converted to energy too?

Because I am a little tired to think... For where does the mass difference between the W and Z bosons come from?

What i mean is: are there currently Higgs Bosons in the universe or the only place where they exist now is if man (or some other technological being) recreates special conditions like in a particle accelerator? Another related question of mine is: some particles "receive" their mass from the...

Homework Statement A particle of mass m is confined to the region |x| < a in one dimension by an infinite square-well potential. Solve for the energies and corresponding normalized energy eigenfunctions of the ground and first excited states. (b) Two particles are confined in the same...

Hi all, I have the following exercise about the The electroweak gauge bosons commutations relations: Homework Statement If ## [ \tau_i ,\tau_k] = 2 i \epsilon_{ikl} \tau_l ## and ## \{ \tau_i ,\tau_k\} = 2 \delta_{ik} ## where ## \bar{\tau} ## are the Pauli matrices, Then...

I mean Goldstone bosons in the title. Sorry I don't know how to edit the title. Goldstone's Theorem says that there is a massless Goldstone mode for each breaking symmetry. For instance symmetry of a theory is broken from SU(N) to SU(N-1), the # of Goldstone bosons is (N^2-1)-((N-1)^2-1)=2N-1...

I read this on a website called Physics for Idiots "If an electron gets near another electron it emits a virtual photon which is absorbed by the second electron and let's it know it need to move away." If a virtual photon is absorbed, doesn't than make it real, and so break conservation...

To take into account the density of states for an ideal gas, we first calculate it ignoring the spin. Then to take into account the spin for a system of electrons we put the number 2 for two spin directions. Why don't we do such this for a boson gas? For example if we have a gas of spin 1...

The detection of spin in Hadrons and Leptons is done through magnetism, a spin 1/2 particle has two states in a magnetic field, an up particle goes up, a down particle goes down. A spin 1 particle has three states, an up/up goes up, a up/down stays straight and a down/down goes down. A spin 3/2...

I have been looking around on the web and in books to clarify this, but can't find a good explanation describing relationship/difference between gapless modes/excitations and Goldsone modes/bosons in Condensed matter physics. Does the term "gapless modes" mean that no energy is required for...

Homework Statement In a system with equidistant energy levels how many ways can you distribute 10 units of energy among 5 bosons? The energy of the ground state(i=0) is 0, and the energy levels are at equal distances from each other. Homework Equations The Attempt at a Solution

Another probably very retarded question I am affraid.Ive only recently been studying all this of my own back so please bare with me. Firstly as i understand it a Photon carries electromagnatism Z and W Bosons carry the strong and weak nuclear forces and the Higgs boson is the missing gravity...

The leptons and hadrons carry the weak isospin charge. What allows the weak bosons do carry the charge? Is it because they have a mass?

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...