All Questions
44
questions
0
votes
1
answer
106
views
Does every field correspond to a particle?
I know that particles in QFT are just excitations of its corresponding field. But is it possible to have a field which cannot generate particles?
If yes, what terms must be added to the Lagrangian so ...
- 1,611
0
votes
2
answers
112
views
Are particles and waves limits of quantum fields?
In quantum field theory we often hear that particles sometimes behave like waves and sometimes behave like particles.
In quantum field theory we say particles are fundamentally fields.
Is it correct ...
- 525
1
vote
1
answer
128
views
Why are the field operator eigenstates a complete basis of the Fock space? How to properly define the measure $\mathcal{D}\Phi(x)$?
This is a question which has plagued me for a long time.
In the path Integral, we insert$\int\mathcal{D}\Phi(x)\vert\Phi\rangle\langle\Phi\vert=\mathcal{I}$ and $\int\mathcal{D}\Pi(x)\vert\Pi\rangle\...
- 619
2
votes
1
answer
1k
views
Why are particles still a thing? [closed]
Couldn't we just assume that waves have mass and momentum and can become localized? Dirac Deltas can be given a rigorous mathematical foundation but physicist do not use the Gelfand triple. Why not ...
- 83
-1
votes
3
answers
229
views
Why do quantum fields correspond to particle type instead of operator type?
I know from the accepted answer to What is the mathematical relationship between the wave functions of QM and the fields in QFT? that "the fields are operator-valued functions of space and time&...
- 2,327
1
vote
2
answers
137
views
Do fields and particles have a one-to-one correspondence?
Do fields and particles have a one-to-one correspondence? That is can we have two different particle from same field (excitation) or can one unique particle gets created by different field (excitation)...
- 1
3
votes
0
answers
162
views
What are particles and fields in QFT?
I have known about QFT for quite some time now and the popular description of what a particle is in QFT is an "excitation in the field". This made me believe that a field is a physical field ...
- 1,747
0
votes
0
answers
268
views
Addition of four-momenta in scattering amplitude of nucleon-anti-nucleon pair in scalar Yakuwa theory
Intro
I'm studying QFT using David Tong's lecture notes. In section 3.5 on examples of scattering amplitudes in scalar Yukawa theory, the scattering amplitude $A$ of a nucleon-anti-nucleon scattering ...
1
vote
1
answer
288
views
Fundamental Particles (Quarks) and Quantum Fields
From what I have understood while studying quantum and particle physics is that all the particles are excitations of their respective fields.
This makes me wonder if elementary particles like quarks ...
- 33
1
vote
4
answers
676
views
What is the analog to the electric field for those particles (different to photon) that have a polarisation?
Photon has a polarisation. The polarisation defines how the two components of the electric field evolves with times in the transverse plane.
Those particles, different to photon, that have a spin $s$ ...
0
votes
1
answer
100
views
Quanta of fields
I just heard the term quanta of a field. I’m trying to understand it. Does it mean that field starts acting in a way that is measurable or singularly measurable? Almost as if the “density” or some ...
- 13
0
votes
1
answer
232
views
Hypercharge of the complex scalar doublet
I often see the complex scalar doublet $Φ_A$, $A=1,2$ with the opposite hypercharge arising in the Yukawa couplings as $\tildeΦ_A = iτ{_2}_{AB}Φ_B^*$ where $τ_r$ $(r=1,2,3)$ denote isospin pauli ...
- 343
0
votes
2
answers
754
views
How is the higgs field excited to give a Higgs boson?
I understand that the excitation of the Higgs field itself is the Higgs boson, and not the Higgs field itself, which does fit somewhat into the little String theory I've read (The excitations of the ...
- 152
1
vote
1
answer
174
views
What is the difference between local and global symmetries in terms of properties of the particle spectrum?
I know that a global symmetry implies the presence of a conserved charge but how it does affect the particle spectrum? and in this sense what is the difference with a gauge symmetry?
- 11
0
votes
2
answers
445
views
How does a particle interact with a quantum field?
I've read many things about particles "swimming" in a quantum field, but what exactly does this mean? At the quantum level, I understand that a particle (like a quark and perhaps even further down to ...
- 4,783