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5

The photon implements the electromagnetic force - it interacts with charged particles. Because the Higgs boson is neutral, it cannot (directly) interact with the photon. Another reason why the Higgs boson and the photon cannot (directly) interact is that interactions with the Higgs boson result in mass (after electroweak symmetry breaking). The photon is ...


2

If you are considering massless neutrinos there is no such a diagram since all interactions would preserve flavor. If you take instead massive neutrinos, you are probing lepton flavor violation within the SM since the new interaction with $\varphi$ respects flavor. It is thus very very small, being controlled by the neutrino masses. In turn, it is therefore ...


4

The $SU(2) \times U(1)$ electroweak gauge theory has 4 symmetry generators, of which the vacuum breaks only three -- corresponding to $W^+$, $W^-$ and $Z$. The vacuum is symmetric under the generator of electromagnetism, hence the photon cannot interact with the vacuum. Think of the vacuum as a medium -- if it was not symmetric under EM, then it could ...


4

The difference between the Higgs boson and the bosons of the three/four fundamental (depending whether you include gravity as a quantized theory or not) actions is that the latter are associated with gauge symmetries, while the Higgs plays a role in spontaneous symmetry breaking. Photons, W- and Z-bosons, gluons and gravitons arise from the requirement that ...


1

The easiest way to form $SU(2)$ singlets in the most general way is to use the techniques of Young Tableau. The method is discussed from a physicists perspective in many lecture notes online. One such example is given here. Using such method its easy to show that 2 lepton doublets make a singlet and a triplet under $SU(2)$, \begin{equation} 2 \otimes 2 = 3 ...


2

The interaction term disappears because when you integrate out the right handed neutrinos you insert in a linear combination of the other fields in their place. For example I expect that we would have something of the form, \begin{equation} G _{ ij} \sigma \bar{\nu} _L ^i \nu _R ^j \rightarrow G _{ij} G _{jk}\sigma ^2 \bar{\nu} _L ^i \nu _L ^k ...


5

Yes, massive particles such as W-bosons, Z-bosons, quarks, and leptons couple to the Higgs field via the cubic (Yukawa) interaction, so they may also exchange the virtual Higgs. Yes, because the virtual particle is massive, one gets the Yukawa potential that includes the exponential dumping with distance. This "Higgs force" is much less fundamental and ...


0

Le us start with what is a field in physics : A field is a physical quantity that has a value for each point in space and time.1 For example, in a weather forecast, the wind velocity is described by assigning a vector to each point on a map. Each vector represents the speed and direction of the movement of air at that point. A field can be ...


0

One can say electric and magnetic fields emerge macroscopically from the quantum theory of interactions between photons and matter, that is to say quantum electrodynamics. In this sense the electromagnetic field "doesn't exist": it can be viewed as a macroscopic effect of some interaction between particles


2

You should take it completely literally. (Quibbles about the Higgs field vs the Higgs boson are misguided. Particles don't acquire masses until the point at which the Higgs boson appears, so attributing the particle masses to the Higgs boson is just as correct.) However, there is a simple way to picture this. The concept of a Higgs boson is completely ...


10

"Binding a massless particle into a small space" is a good phrase for a popular discussion, but it is not the only way to picture the Higgs mechanism. Another perspective comes from the fact that every particle inside some interaction field behaves exactly like its energy or momentum has changed. This concept is called canonical momentum, in contrast to the ...


1

The plots are "expected from background" (thin line) vs "observed" (thick line); the horizontal axis is energy (in GeV), with a peak at 125 GeV. On the left is the raw data - the frequency with which certain energies were observed (note it's a log axis); the plot on the right is the "statistical significance" in standard deviations. The peak is at 5 sigma - ...


0

No, Higgs particles do not contribute to Casimir forces. Casimir effect happens because virtual particles are excluded from the gap between two solids when the separation distance is smaller than the particle wavelength (multiplied by smallish integers). Caveat: I understand the principles here sufficiently for a rough explanation, but not nearly enough to ...


4

A standard simple answer (for the standard Higgs boson field) is that a particle acquires mass by passing through this field, which changes the particle's inertia (thus appearing as acquiring mass which is a measure of inertia among others) Of course the standard Higgs boson is still investigated (if it is the standard one and not some variation of other ...


7

Notwithstanding the previous answers, bear in mind that the Higgs boson fields is pervasive throughout the whole universe, according to the Standard Model of particle physics. The interaction between the Higgs field and the matter fermion fields (quarks, electron, muon, etc) provides the fermions with mass. This means that there are virtual Higgs bosons ...


16

Short answer: do not take it literally, without further context. In order to understand the Higgs boson's role in the Standard model, it is necessary to take a closer look at the framework in which we describe elementary particles: quantum field theory. In this approach, particles are described as excitations of fields that spans all spacetime. The ground ...


98

The Higgs field (note it is the field that is important here, not the Higgs boson itself, which is just a ripple in the Higgs field) gives particles mass in the same sense that the strong force gives the proton mass (context: $99\%$ of the mass of the proton comes not from the mass of its constituent quarks, but from the fact that roughly speaking the quarks ...


33

You probably know that the mass of the Higgs boson is around $125$ GeV, which means the energy it takes to create a Higgs boson is around $125$ GeV and therefore that the temperature at which significant numbers of Higgs bosons will be created will be given by $kT = 125$ GeV. One GeV is $1.602 \times 10^{-10}$J, so the corresponding temperature is around ...



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