Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userOn the continuum limit of gauge-fixed compact U(1) lattice gauge theory
58
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
We investigate the continuum limit of a compact formulation of the lattice U(1) gauge theory in 4 dimensions using a nonperturbative gauge-fixed regularization. We find clear evidence of a continuous phase transition in the pure gauge theory for all values of the gauge coupling (with gauge symmetry restored). When probed with quenched staggered fermions with U(1) charge, the theory clearly has a chiral transition for large gauge couplings. We identify the only possible region in the parameter space where a continuum limit with nonperturbative physics may appear.
rate research
Read More
A conceptually simple model for strongly interacting compact U(1) lattice gauge theory is expressed as operators acting on qubits. The number of independent gauge links is reduced to its minimum through the use of Gausss law. The model can be implemented with any number of qubits per gauge link, and a choice as small as two is shown to be useful. Real-time propagation and real-time collisions are observed on lattices in two spatial dimensions. The extension to three spatial dimensions is also developed, and a first look at 3-dimensional real-time dynamics is presented.
We study the U(2) lattice gauge theory in the pure gauge sector using the simplest action, with determinant and fundamental terms, having the naive continuum limit of SU(2)$times$U(1). We determine part of the phase diagram of the model and find a first-order critical line which goes through the U(1) critical point. We show how to deduce both the order parameter of the first-order transition and the U(2) renormalization group flow from the lattice potential in the determinant and fundamental representations. We give evidence that a Monte-Carlo simulation of the model is indeed consistent with the symmetric SU(2)$times$U(1) continuum limit in the weak coupling pertubative regime.
In 4D compact U(1) lattice gauge theory with a monopole term added to the Wilson action we first reveal some properties of a third phase region at negative $beta$. Then at some larger values of the monopole coupling $lambda$ by a finite-size analysis we find values of the critical exponent $ u$ close to, however, different from the Gaussian value.
We investigate four-dimensional compact U(1) lattice gauge theory with a monopole term added to the Wilson action. First we consider the phase structure at negative $beta$, revealing some properties of a third phase region there, in particular the existence of a number of different states. Then our present studies concentrate on larger values of the monopole coupling $lambda$ where the confinement-Coulomb phase transition turns out to become of second order. Performing a finite-size analysis we find that the critical exponent $ u$ is close to, however, different from the gaussian value and that in the range considered $ u$ increases somewhat with $lambda$.
Monte Carlo simulation of gauge theories with a $theta$ term is known to be extremely difficult due to the sign problem. Recently there has been major progress in solving this problem based on the idea of complexifying dynamical variables. Here we consider the complex Langevin method (CLM), which is a promising approach for its low computational cost. The drawback of this method, however, is the existence of a condition that has to be met in order for the results to be correct. As a first step, we apply the method to 2D U(1) gauge theory on a torus with a $theta$ term, which can be solved analytically. We find that a naive implementation of the method fails because of the topological nature of the $theta$ term. In order to circumvent this problem, we simulate the same theory on a punctured torus, which is equivalent to the original model in the infinite volume limit for $ |theta| < pi$. Rather surprisingly, we find that the CLM works and reproduces the exact results for a punctured torus even at large $theta$, where the link variables near the puncture become very far from being unitary.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
