Search Results
Search type | Search syntax |
---|---|
Tags | [tag] |
Exact | "words here" |
Author |
user:1234 user:me (yours) |
Score |
score:3 (3+) score:0 (none) |
Answers |
answers:3 (3+) answers:0 (none) isaccepted:yes hasaccepted:no inquestion:1234 |
Views | views:250 |
Code | code:"if (foo != bar)" |
Sections |
title:apples body:"apples oranges" |
URL | url:"*.example.com" |
Saves | in:saves |
Status |
closed:yes duplicate:no migrated:no wiki:no |
Types |
is:question is:answer |
Exclude |
-[tag] -apples |
For more details on advanced search visit our help page |
In physics, an operator is almost always either a square matrix or a linear mapping between two function spaces (defined on, say, $\mathbb R^n$). Operators serve as observables and as time evolution operators in Quantum Mechanics. This tag will most often find valid use in quantum mechanics; don't use this tag just because your equations contain "everyday operations" like $\times$, $+$!
1
vote
0
answers
50
views
Expansion of trace of operator
I am looking for a way to rewrite this trace "at leading order in $a$"
$$
\text{Tr}(-a\nabla^2+A(r))
$$
Would it be possible to expand this trace if my parameter $a$ is small, $a<<1$ (which is the cas …
3
votes
1
answer
74
views
Infinitesimal generator
From Conformal field theory (Di Francesco, Pierre Mathieu):
We now study the effect of infinitesimal transformations on the action. Such transformations may in general be written as
$$
\begin{aligned …
0
votes
1
answer
72
views
Hausdorff formula for Dilatation operator
Using the Hausdorff formula I can find the dilation operator at all position:
$$
e^{i x^\rho P_\rho} D e^{-i x^\rho P_\rho}=D+\left[D,-i x^\rho P_\rho\right]+\frac{1}{2}\left[\left[D,-i x^\rho P_\rho\ …
1
vote
0
answers
144
views
Scalar Yukawa theory, contraction
In the scalar Yukawa theory ($\Phi$ is real scalar field and $\phi$ is a complex scalar field):
\begin{equation}
\mathcal{L}_{S Y}=\left(|\partial \phi|^{2}-m^{2}|\phi|^{2}\right)+\frac{1}{2}\left((\p …