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Dong-Shin Shin

Publications and source records attributed to Dong-Shin Shin.

7 recordsLinked to original sources
arXiv2001

A determination of the mass gap in the O(n) sigma model

We calculate the finite volume mass gap $M(L)$ at 3-loop level in the non-linear O($n$) $σ$-model in two dimensions in small volumes. By applying the Monte Carlo measurements of the running coupling $\bar g^2(L)=2nM(L)L/(n-1)$ by Lüscher, Weisz and Wolff measured in units of the physical mass gap $m$, the result is used to determine $m$ in units of the $Λ$-parameter in the O(3) and O(4) models. Our determinations show good agreement with those by Hasenfratz, Maggiore and Niedermayer in both models. We note that this manuscript has been revised in our paper hep-lat/9810025 by using the corrected four-loop $β$-function on the lattice.

hep-lat↗
arXiv2001

Correction to four-loop RG functions in the two-dimensional lattice O(n) $σ$-model

We report the result of our evaluation of the Feynman diagrams appearing in the determination of the four-loop renormalization group functions in the two-dimensional lattice O($n$) $σ$-model by Caracciolo and Pelissetto. In the list of the integrals used for the determination of those functions, we find that three entries were not correctly evaluated. We give the values for them corrected by us including those for all other integrals which we computed with higher precision. These results are then applied to revise the determination of the second analytic correction to correlation length $ξ$ and spin susceptibility $χ$ by Caracciolo et al. as well as our determination of the mass gap by means of a finite volume technique where we explicitly made use of the four-loop $β$-function. In both cases we find sizeable changes in predictions. In the meantime there appeared a paper by Alles et al. where they revised one finite integral in the list of our corrected integrals. After having taken the new revised value into consideration, we found that there are no noticeable changes in the perturbative predictions of the present paper including the final conclusions.

hep-lat↗
arXiv2001

Numerical evidence for monopoles in 3-dimensional Yang-Mills theory

Recently Anishetty, Majumdar and Sharatchandra have proposed a way of characterizing topologically non-trivial configurations for 2+1 dimensional Yang-Mills theory in a local and manifestly gauge invariant manner. In this paper paper we develop criteria to locate such objects in lattice gauge theory and find them in numerical simulations.

hep-lat↗
arXiv2000

Current Status of the Numerical Simulations of d=3 SU(2) Lattice Gauge Theory in the Dual Formulation

We have continued our systematic investigations of the numerical simulations of lattice gauge theories in the dual formulation. These include: i) a more practical implementation of the quasi-local updating technique, ii) a thorough investigation of the sign problem, iii) issues related to the ergodicity of the various update algorithms, iv) a novel way of measuring conventional observables like plaquette in the dual formalism and v) investigations of thermalisation. While the dual formulation holds out a lot of promises in principle, there are still some ways to go before it can be made into an attractive alternative lattice formulation.

hep-lat↗
arXiv2000

Topologically non-trivial configurations in 3-dimensional Yang-Mills theory

Recently Anishetty, Majumdar and Sharatchandra have proposed a way of characterizing topologically non-trivial configurations for 2+1-dimensional Yang-Mills theory in a local and manifestly gauge invariant manner. Here we develop criteria to locate such objects in lattice gauge theory and find them in numerical simulations.

hep-lat↗
arXiv1998

Application of a coordinate space method for the evaluation of lattice Feynman diagrams in two dimensions

We apply a new coordinate space method for the evaluation of lattice Feynman diagrams suggested by Lüscher and Weisz to field theories in two dimensions. Our work is to be presented for the theories with massless propagators. The main idea is to deal with the integrals in position space by making use of the recursion relation for the free propagator $G(x)$ which allows to compute the propagator recursively by its values around origin. It turns out that the method is very efficient and gives very precise results. We illustrate the technique by evaluating a number of two- and three-loop diagrams explicitly.

hep-lat↗