Tagged Questions
9
votes
1answer
105 views
Why are topological solitons present in some phases for lattice models?
Over a spatial continuum, it is easy to see why some topological solitons like vortices and monopoles have to be stable. For similar reasons, Skyrmions also have to be stable, with a conserved ...
7
votes
0answers
189 views
How to determine if an emergent gauge theory is deconfined or not?
2+1D lattice gauge theory can emerge in a spin system through fractionalization. Usually if the gauge structure is broken down to $\mathbb{Z}_N$, it is believed that the fractionalized spinons are ...
1
vote
1answer
96 views
One-Plaquette Action and SU(2)'s Irreducible Representations
I have a typical single-plaquette partition function for a gauge-field
$$ Z=\int [d U_{\text{link}}] \exp[-\sum_{p} S_{p}(U,a)]$$
with $U$ as the product of the the $U$'s assigned to each link around ...
3
votes
1answer
141 views
Why does the creation operator take a continuum value for the momentum?
Imagine that you have a lattice and a set of masses. Each mass at a lattice point. Now each two neighbouring masses are connected with spring.
Now in Classical Mechanics (CM) the ground state is the ...
8
votes
2answers
136 views
Are there rigorous constructions of the path integral for lattice QFT on an infinite lattice?
Lattice QFT on a finite lattice* is a completely well defined mathematical object. This is because the path integral is an ordinary finite-dimensional integral. However, if the lattice is infinite, ...
25
votes
3answers
166 views
Continuum theory from lattice theory
I am looking for references on how to obtain continuum theories from lattice theories. There are basically a few questions that I am interested in, but any references are welcome. For example, you can ...
10
votes
2answers
693 views
What is the fundamental reason of the fermion doubling?
Recall that the fermion doubling is the problem in taking the $a \to 0$ limit of a naively discretized fermionic theory (defined on a lattice with lattice spacing $a$). After such a limit one finds ...
