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[Licence| Download | New Version Template] aels_v2_0.tar.gz(1264 Kbytes)
Manuscript Title: Parallel software for lattice N = 4 supersymmetric Yang-Mills theory
Authors: David Schaich, Thomas DeGrand
Program title: SUSY LATTICE
Catalogue identifier: AELS_v2_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 190(2015)200
Programming language: C.
Operating system: Any, tested on Linux workstations and MPI clusters with InfiniBand.
Has the code been vectorised or parallelized?: Code is parallelized
Keywords: Lattice gauge theory, Supersymmetric Yang-Mills, Monte Carlo methods, Parallel computing.
PACS: 11.15.Ha, 12.60.Jv, 02.70.Uu.
Classification: 11.5.

External routines: Lapack, Blas, Primme (optional)

Does the new version supersede the previous version?: Yes

Nature of problem:
To carry out non-perturbative Monte Carlo importance sampling for maximally supersymmetric Yang-Mills theories in two and four dimensions, and thereby compute observables including Wilson loops, fermion bilinears, eigenvalues of DD and the Pfaffian of the sparse fermion operator D.

Solution method:
The central application is a rational hybrid Monte Carlo algorithm with a two-level Omelyan molecular dynamics integrator. Gauge field configurations generated by this application may be saved to disk for subsequent measurements of additional observables. Input parameters for either configuration generation or analysis may be entered manually or read from a file.

Reasons for new version:
The code is parallelized to improve performance and scalability. In addition, several new features and measurements are provided.

Summary of revisions:
The program is completely rewritten on the basis of the MILC code for lattice QCD, and several new features and measurements are added.

Restrictions:
The code is currently restricted to two-dimensional N = (2,2) and four-dimensional N = 4 supersymmetric Yang-Mills theories. The process of topological twisting on which it is based can also be applied to a few other systems, as discussed in Sections 1 and 5.

Additional comments:
Further documentation is provided in the distribution file, including a set of test runs with reference output in the testsuite directory.

Running time:
From seconds to hours depending on the computational task, lattice volume, gauge group, and desired statistics, as well as on the computing platform and number of cores used. For example, rational hybrid Monte Carlo generation of 50 molecular dynamics time units for a 163x32 lattice volume with gauge group U(2) takes approximately 16 hours on 512 cores of the USQCD bc cluster at Fermilab, while standard measurements on a saved 83x24 U(2) configuration require only 8 seconds on one eight-core workstation.