Questions tagged [carrier-particles]
Use for force carrier particles, quanta of characteristic quantum fields, usually gauge fields, such as the quanta of electromagnetic fields (photons), of the electroweak interactions (EW bosons), and of the strong interactions (gluons); elastic forces on on a lattice (phonons); nuclear forces (pions); gravity forces (gravitons), etc. May include conjectural particles from GUTS (like their proton-decay-inducing gauge bosons).
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Understanding Virtual Particles and the Mediation of Forces
When trying to understand how the electromagnetic force works in a Quantum-Mechanic context (what mediates it), one concept you will quickly encounter is that of virtual photons (and more generally ...
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Does a massless boson imply an infinite interaction distance?
As we know, if we use the Lagrangian of electrodynamics we can find that the photon has no mass. If the photon had mass, it would even have 3 polarizations, which is a consequence of having mass. My ...
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Why did Peter Higgs, et al. suspect that the $W$ boson(s) had mass? All the way back in 1963, '64?
I cannot understand why so many people (the PRL Symmetry authors) were so sure that the weak interaction particles had mass.
The gluon, for instance, and its attendant strong force are also very short ...
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Why are $W$ and $Z$ bosons called 'intermediate' vector bosons?
What does the 'intermediate' part mean? Somehow, I thought an answer would be easy to come across, but I have yet to find one.
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Are gravitons suggested as the cause of matter curving space?
My understand is that GR says that mass curves space but it does not say why or how this occurs. Is the idea of gravitons that they are the entities that actually affect space?
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What is the current most widely-accepted explanation of gravity? [closed]
What do physicists typically say gives gravity the ability to act on a pair of objects?
I am not asking for a description of gravity as a scalar field, but rather what the current accepted theory is ...
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Understanding attractive/repulsive boson-mediated forces based on interference of free-space fields
I just worked through the derivations of the Yukawa interaction for scalar and spin one particles (i.e. Peskin and Schroeder, end of chapter 4, which covers the tree-level Feynman diagram). It's very ...
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Can the Coulomb potential as the vacuum energy shift in QED also be calculated with a field quantized in the Coulomb gauge?
This answer explains how the Coulomb-potential can be calculated as the energy shift of the (photon) ground state for 2 charges fixed in place. This calculation has been done for a covariant "...
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How forces are mediated if virtual particles are only a mathematical artifacts? [duplicate]
I was reading this post, that discusses whether if virtual particles do exist; stating that they are only a mathematical artifact that arises from perturbation theory. My question is, if virtual ...
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Why do gravity and electricity sometimes obey inverse square laws over the same distance scale?
Is this a chance mathematical coincidence or is there a good physical explanation for it?
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Does quantum field theory forbid spin-2 gravitons from carrying a charge that would make them repel each other increasingly with decreasing distance? [closed]
Can repulsive gravitons account for why gravity is weak compared to other forces and would they stop singularities from forming?
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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 force is the axion the mediator of? [closed]
I keep seeing in the literature that the axion is a force-carrier. I assume this is because it has spin 0, and all integer-spin particles are force-carriers. But I cannot find anywhere what force ...
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Why do gauge particles with odd spin cause opposite charges to attract, while those with even spin cause them to repel? What's the math behind it?
I have read that opposite charges attract when mediated by odd-spin gauge particles, like the photon, and that they repel when mediated by even-spin gauge particles, like the graviton.
Is there an ...
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Do gravitons refer to gravity or to gravitational waves?
I am confused about what gravitons exactly are.
On the one hand it is said that gravitons are presumed to represent gravity (see Wikipedia "Graviton" : "In theories of quantum gravity, ...
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Inverse square law of a photon in QED
So in Feynman's QED book strange theory of light and matter, he mentioned as a photon travels, it spreads a little, thus the "arrow" shrinks inversely with distance, and that is the inverse ...
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Is there any empirical evidence for the existence of the graviton?
In the standard model of particle physics, there are four fundamental forces/interactions, each governed or conveyed by its respective fundamental particle:
Strong force: quark/gluons
Weak force: ...
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What does it mean that forces are carried by virtual particles, since virtual particles are just math?
According to PBS Spacetime and other reputable sources, virtual particles are really just a handy math trick that make it easier to solve certain problems in quantum field theory, but aren't strictly ...
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How do particles attract? [duplicate]
Particles of the same charge repel one another by "throwing" a virtual photon back and forth. Because the momentum of the virtual photon gets absorbed by the particles, they push each other ...
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What causes the difference in ranges of forces?
What causes the difference in ranges of forces? In other words, why is it that the weak force acts only at small distances whereas the Coulomb force has a very large range?
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Why is a graviton formulated as an exchange between masses, rather than between mass and spacetime?
In Sean Carroll's Lecture Notes on General Relativity he states:
The gravitational interaction, meanwhile, can be thought of as due to exchange of a virtual graviton (a quantized perturbation of the ...
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How to describe electron-electron repulsion using virtual photon exchange? [duplicate]
Electron-electron repulsion can be described deterministically using Coulomb's law $$F = k\frac{e^2}{r^2}$$
Given two initially stationary electrons, the complete time evolution (distances apart, ...
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What is the actual carrier of the strong force? [duplicate]
I have been digging into the particle physics recently and I have found two different answers for this question. First of all, according to Wikipedia the Pion is a meson that acts as the carrier ...
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Why quantum gravity can't be described by spin-1 bosons? [duplicate]
As the title suggests, why quantum gravity can't be described by spin-1 gravitons?
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How does energy/momentum/information transferred to carriers?
The forces , interaction , momentum , information , etc . are transferred through carriers like photons . However , how do the carriers themselves get momentum, information and interactions ? What ...
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Is there some mathematical or physical model that postulates that gravitons exist? [duplicate]
Is there some model, mathematical or physical, that postulates that gravitons exist? For example is there mass missing from some particle decay that is thought to form gravitons? Or something in the ...
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What makes a photon a photon?
As i understand photons are excitation of the electromagnetic field. Therefore charged particles are affected by this excitation. But what if we have (highly theoretically) a particle that has the ...
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Attractiveness of Coulomb potential from Peskin-Schroeder textbook
On page 125 chapter 4.8 of Peskin & Schroeder "An Introduction To Quantum Field Theory" there's a sort of argument that should prove that in the non-relativistic limit of QED like ...
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How can I see mathematically with Feynman rules of QED that same charges repel and opposite charges attract?
I'm trying to 'prove' that electrons repel each other and electrons-positrons attract each other, but I'm not sure what I should be looking at. My guess is that there should be a different sign when ...
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How can the same virtual particle both attract and repel charged particles together?
so I've read a lot of things about QED and stuff, and I've clearly understood that charged particles are in fact "charged" because they exchange virtual photons, small packets of energy with ...
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How is it possible for $W$-boson to be so heavy when neutron and proton have similar mass? [duplicate]
I know that in a beta decay a neutron turns into a proton and a $W$-boson. I know that a $W$-boson is very heavy, so I intuitively expect the proton to by much lighter than neutron — I would expect ...
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Does the existence of exchange particles imply that that the 4 fundamental forces are delivered in discrete packets instead of continuously?
If exchange particles transfer the fundamental forces and these particles takes some amount of time to transfer this force does this mean there is a rate of force?
(Side question: if two oppositely ...
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Gravitational Waves and Quantum Gravity [duplicate]
Since we can now directly observe gravitational wave signals, can any type of future experiment be set up that might manifest the quantum nature of gravity? For example, perhaps a version of LIGO ...
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Fundamental-ness of fundamental forces
Example :
Consider a black hole and it's event horizon of radius R surrounding it . Suppose in the direction of a diameter of the black hole ( or event horizon) , there are two charged particles. ...
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Virtual photons
Is it true what is said about photons that carry electromagnetic force or field? are they virtual photons too? Where exist real photons?
I don't understand the concept of virtual photon, in ...
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Does discovery of graviton disprove wormhole since latter is applicable in GR only?
I know graviton is only a hypothetical particle invented probably to serve as a placeholder in standard model, but suppose one day we discovered graviton, does this disprove the existence of wormhole ...
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Would Gravitons have Gravity in it of themselves?
If you held a handful of gravitons, would you be holding a handful of gravity, drawing things towards it, or do gravitons have to be exchanged or transmitted for gravity to take effect, in which case, ...
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How do Gravitons work? as compared to photons
Photons are to Electrons as Gravitons are to ... what?
What is it that 'emits' a graviton? And what 'absorbs' it?
I've been looking for a good layman's description of how gravitons interact with ... ...
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How does existence of graviton helps explain 2 different objects fall at the same rate?
Actually I want to see how gravitons help to explain why a feather and a bowling ball would fall at the same rate towards the ground assuming no air resistance, I would imagine bowling ball to emit ...
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How do gravitons escape each other's gravity to spread out and form a field?
The hypothetical graviton I'm familiar with is a spin-2 particle. That implies it has angular momentum, which further implies it has energy. If energy attracts energy, what prevents gravitons from ...
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Understanding attractive Feynman diagram [duplicate]
I’m curious about the origins of the positive/negative charge and why there might be the two, and only the two, electric charges. I saw a great example just now which I think was referencing a Feynman ...
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Mathematically, what is a graviton?
There are numerous questions on this site asking what a graviton is, but almost all the answers are superficial. I am hoping for a more formal answer.
All I know in the here and now, is that it has ...
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A question on the electrostrong force
I understand that the strong nuclear force is carried by gluons, the electromagnetic force is carried by photons and the weak nuclear force is carried by the $W$ and $Z$ bosons. However, in the ...
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Protons and QED
I have been researching quantum electrodynamics recently and I have found out that when electrons repel each other, they constantly exchange photons with each other. When two protons repel, do they ...
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Would there be a force carrier particle in the unified field theory?
So from what I understand, each fundamental force (with the exception of gravity unless you count the hypothetical graviton) has a force carrier particle that mediates the force. Does that mean if the ...
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What are gravitons made of? And how do they cause gravity? [closed]
What are gravitons made of and how do they cause gravity? Why do bodies with more mass attract more gravitons and hence have a greater gravitational pull? I heard that nobody quite exactly knows this (...
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Does the weak force get transmitted at speeds less than $c$?
The force carrier of EM is the photon (or off-shell photons at least). These are massless field disturbances. However the force carriers in Weak interactions are the $W$ and $Z$ bosons. Having mass, ...
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If the exchange of virtual Gravitons isn't real why do bodies attract?
I have been told Earth is not really sending particles to me and keeping me on the ground. That it is just a convenient thing to do in calculations.
However if the exchange of gravitons isn't real, ...
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What does "propagate" mean in QFT?
Studying QFT, one finds the term "the field propagates" and I'm not sure I understand what it means. For example, in QED, one finds that $A_0$ "doesn't propagate" because its ...
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How do Gravitons work?
Gravitons are supposed to mediate the force of gravity, but wouldn't that require Earth, Sun and basically everything else is constantly sending out gravitons to everything else?
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