Tagged Questions
-1
votes
1answer
111 views
Double- well potential and Mexican potential
Is double well potential related to Maxican hat potential?
I have found on Quantum Field Theory in a Nutshell
by A. Zee
He wrote the double well potential as : $V (φ) = (λ/4)(φ^ 2 − v^2)^2$.
Can ...
0
votes
1answer
102 views
Interaction potential analysis from $\phi^4$ model
In this paper, the authors consider a real scalar field theory in $d$-dimensional flat Minkowski space-time, with the action given by
$$S=\int d^d\! x ...
-3
votes
1answer
227 views
Creation and Annihilation operator [closed]
In this page I want to know, why the equation (1.32) introduced creation and annihilation operator. Please elaborate.
0
votes
2answers
151 views
Difficulties with bra and ket notation
I have problem in understanding equation (1.23), I croped this image from Mark_Srednicki "Quantum field theory". Can anyone show me the reason for the equation (1.23)?
4
votes
1answer
164 views
Quantum Field Theory: why fields are equal to zero on the boundary?
One of the first assumptions, when introducing the Lagrangian and Hamiltonian in an undergraduate course on QFT is
$$
\phi(x)=0\,\text{on the boundary}
$$
and this is widely used in many situations ...
8
votes
4answers
468 views
Quantum mechanics as classical field theory
Can we view the normal, non-relativistic quantum mechanics as a classical fields?
I know, that one can derive the Schrödinger equation from the Lagrangian density
$${\cal L} ~=~ \frac{i\hbar}{2} ...
7
votes
1answer
363 views
Is Bose-Einstein condensate a good example of a classical massive boson field?
Physically, we know that a BEC has formed if a macroscopic number of bosons occupy a single quantum state. The wave-function $\Psi(x)$ of the latter, normalized to the total number of condensed atoms ...
8
votes
2answers
319 views
Quantizing EM field
Why when we quantize EM field, whe quantize the vector potential $A^\mu$ obtaining vectorial particles (photons) like the elastic field (phonons) and we can't quantize directly the EM-field tensor ...
4
votes
2answers
846 views
What does a Field Theory mean?
What exactly is a field theory?
How do we classify theories as field theories and non field theories?
EDIT:
After reading the answers I am under the impression that almost every theory is a ...
