All Questions
Tagged with locality interactions
13
questions
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Can you model relativistic interactions without locality?
Assume $c=1$
I've been doing relativity by myself so I may be making some assumptions here that I would not have if my learning had been more extensive.
One such assumption is that you can model the ...
- 312
16
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6
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Are field theories necessary to make accurate predictions or do they just make calculations easier?
For example, if we really wanted to, could we, at least in principle, model electromagnetism just considering interactions between charged particles without using the EM field? That is, is it ...
- 2,327
2
votes
1
answer
85
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Non- Local operators and Entanglement
Given a separable state, $|\psi\rangle$ = $|a\rangle\otimes|b\rangle$, operating on this state with a local operator of the form, $A\otimes B$ will not lead to an entangled state. Is the converse true?...
- 427
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How come subatomic particles interact with each other while not being in contact? [closed]
Although electrons stays away from protons an atom remains electrically neutral
But two atoms one positively charged and another negatively charged remain so until they comes in contact.
Can the ...
3
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1
answer
174
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Why don't there seem to be any dimensionless fields in nature?
Scalar fields have dimension 1, spinor fields dimension 3/2, and vector bosons like the photon dimension 1. According to the principles of renormalizability (along with others), this restricts the ...
- 33
2
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2
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How does the Earth know when to send a graviton to a newly born particle?
Pardon if this is a silly queston, but I'm reading this for the first time. It says that the force we perceive between two objects is an effect of the exchange of the force carrier particles. Even ...
- 1,113
7
votes
1
answer
367
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$\phi^{n}$ quantum scalar field theories where $n$ is not an integer
Consider a quantum scalar field theory with interaction terms of the form $\phi^{n}$, where $n$ is not an integer.
Where are some examples of widely-studied quantum field theories which involve such ...
- 3,203
1
vote
1
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Newton's third law at the quantum level? [closed]
let's look at force at the atomic level to understand the newtons third law of motion. I'll use Helium atoms as an example.
Now imagine we start with one atom HE2 stationary, and throw another atom ...
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6
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1
answer
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Is microcausality a statement about locality?
As far as I understand it locality is the rejection of action-at-a-distance. By this I mean that in a given frame of reference at a given instant of time (in that reference frame), two physical ...
- 3,063
5
votes
1
answer
613
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Coincidence of spacetime events & Lorentz invariance
Am I correct in thinking that if two spacetime events are coincident in one frame of reference, then they are coincident in all frames of reference, i.e. coincidence of spacetime events is a Lorentz ...
- 3,063
10
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695
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Lorentz invariance, energy-momentum conservation & the locality of interactions
I have been reading these notes ("Minkowski Spacetime: A Hundred Years Later", by Vesselin Petkov) 1,
in which the author states (in the middle of the text on page 137)
that
"The only Lorentz ...
- 3,063
0
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0
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105
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Lagrangians densities & interactions in field theory
To avoid ambiguity, this question pertains to the construction of Lagrangian densities (including interaction terms) in terms of their values at single points in spacetime.
In classical mechanics in ...
- 3,063
7
votes
2
answers
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Why is lagrangian density with interactions correct?
The textbooks I have available explain that due to the infinite degrees of freedom of a field, the relevant object in QFT is the Lagrangian density. A Lagrangian is then obtained for the field by ...
- 4,036