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0 answers
50 views

Exactly what value does the Wilson line take?

Let $G$ be the Lie group of a given theory with the Lie algebra $\mathfrak{g}$. According to the Wikipedia article, a Wilson line is of the form \begin{equation} W[x_i,x_f]= P e^{i \int_{x_i}^{x_f} A} ...
Keith's user avatar
  • 1,669
2 votes
0 answers
58 views

Extracting a gauge-invariant variable from a given Wilson line? (NOT Wilson loop)

Let $W[x_i,x_f]$ be the Wilson line as defined here. Under a local gauge transform $g(x)$, it transforms as \begin{equation} W[x_i,x_f] \to g(x_f)W[x_i,x_f] g^{-1}(x_i) \end{equation} which is shown ...
Keith's user avatar
  • 1,669
3 votes
0 answers
79 views

Wilson lines with Chan-Paton factors in string theory

In the context of compactifying the open string with Chan-Paton factors, Polchinski (Volume I Section 8.6) considers a toy example with a point particle of charge $q$ which has the action $$ S = \int ...
Adrien Martina's user avatar
1 vote
0 answers
55 views

Are pseudo Riemannian manifolds with identical Wilson loops isometric?

It is well established that in gauge theory, the Wilson loops of the theory determine the gauge potential up a gauge transformation. That is, two gauge potentials $A_\mu$ and $B_\mu $ produce the same ...
Trevor Scheopner's user avatar
1 vote
1 answer
46 views

What is a non-linear space of connections

In the book "Loops Knots Gauge Theory and Quantum Gravity" when trying to define a loop representation, one needs to integrate over the space of connections (modulo Gauge transformations). ...
Confuse-ray30's user avatar
0 votes
0 answers
27 views

Physical meaning of the Wilson Loops as spin impurities

This is in reference to the paper of David Tong here. In this paper in section 2, it says In this first section, we explain how spin impurities, coupled to bulk gauge fields, can be thought of as ...
Dr. user44690's user avatar
7 votes
1 answer
277 views

Gauge theories, boundaries and Wilson lines

My understanding of Wilson loops Let's work with classical electromagnetism. The 4-potential $A_\mu$ determines the electric and magnetic fields, which are the physical entities responsible for the ...
P. C. Spaniel's user avatar
0 votes
0 answers
114 views

Relationship between holonomy and fundamental group

In my notes of topological QFT we demonstrated that the holonomy associated with a path in $\mathbb{R}^3$ is invariant under smooth deformation of the path if the connection is flat. Then I wrote: If ...
polology's user avatar
  • 167
1 vote
1 answer
99 views

De Rham current associated with knot in abelian CS theory on a generic manifold

I'm studying TQFT and I'm stucked on this part of the paper of my teacher: My teacher didn't explain a lot about it and I've never followed an advanced course on differential geometry or algebraic ...
polology's user avatar
  • 167
1 vote
0 answers
46 views

Holonomy expansion for path deformation

A path deformation by $\epsilon^{\mu}(s)$ induces a variation of the connection $A'(s)=A(s)+\Delta A(s)$. I'm trying to obtain the first-order expansion of the holonomy $H_{\gamma}(A)=Pe^{i\int_{\...
polology's user avatar
  • 167
6 votes
1 answer
180 views

Representation of nonabelian Wilson line in terms of fermionic fields

Context: The coupling action of a particle of charge $q$ to a $U(1)$ gauge field is given by \begin{equation} S = q \int d \tau A_\mu \left( X \right) \frac{dX^\mu(\tau)}{d \tau} = -i \ln W_q, \tag{...
Bairrao's user avatar
  • 897
3 votes
1 answer
126 views

Dressing an operator by Wilson line in Quantum Electrodynamic

I am reading a paper arXiv:1507.07921 which introduce gravitational dressing. The paper compare it to dressing in QED. Consider the scalar QED lagrangian $$\mathcal{L}=-\frac{1}{4}(F^{\mu\nu})^2-|D_\...
gshxd's user avatar
  • 133
5 votes
0 answers
178 views

Can one build Wilson lines in general relativity?

This question has two parts: Firstly, I am curious if one can build Wilson lines as a 'parallel transport operator' in general relativity in direct analogy with what is done in gauge theory. For a ...
Craig's user avatar
  • 1,117
0 votes
0 answers
94 views

Calculating a rectangular Wilson loop for the free photon

I'm studying Creutz's Quarks, gluons and lattices, in chapter 6 on page 33, we have the following exercise Calculate a rectangular Wilson loop for the field theory of free photons. Using any ...
Simplyorange's user avatar
11 votes
1 answer
912 views

Berry phase and Wilson loop

According to the definition, the Wilson loop is \begin{equation} W[\mathcal{C}] =\operatorname{Tr}\left[\mathcal{P} \exp\left\{i\oint _{\mathcal{C}} A_{\mu } dx^{\mu }\right\}\right] \end{equation} ...
Fang Lyu's user avatar
  • 111

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