34 research outputs found
Benchmark results in the 2D lattice Thirring model with a chemical potential
We study the two-dimensional lattice Thirring model in the presence of a fermion chemical potential. Our model is asymptotically free and contains massive fermions that mimic a baryon and light bosons that mimic pions. Hence, it is a useful toy model for QCD, especially since it, too, suffers from a sign problem in the auxiliary field formulation in the presence of a fermion chemical potential. In this work, we formulate the model in both the world line and fermion-bag representations and show that the sign problem can be completely eliminated with open boundary conditions when the fermions are massless. Hence, we are able accurately compute a variety of interesting quantities in the model, and these results could provide benchmarks for other methods that are being developed to solve the sign problem in QCD
The use of Convolutional Neural Networks for signal-background classification in Particle Physics experiments
The success of Convolutional Neural Networks (CNNs) in image classification
has prompted efforts to study their use for classifying image data obtained in
Particle Physics experiments. Here, we discuss our efforts to apply CNNs to 2D
and 3D image data from particle physics experiments to classify signal from
background.
In this work we present an extensive convolutional neural architecture
search, achieving high accuracy for signal/background discrimination for a HEP
classification use-case based on simulated data from the Ice Cube neutrino
observatory and an ATLAS-like detector. We demonstrate among other things that
we can achieve the same accuracy as complex ResNet architectures with CNNs with
less parameters, and present comparisons of computational requirements,
training and inference times.Comment: Contribution to Proceedings of CHEP 2019, Nov 4-8, Adelaide,
Australi
Optimizing Staggered Multigrid for Exascale performance
Adaptive multi-grid methods have proven very successful in dealing with
critical slow down for the Wilson-Dirac solver in lattice gauge theory.
Multi-grid algorithms developed for Staggered fermions using the K\"ahler-Dirac
preconditioning~\cite{Brower:2018ymy} have shown remarkable success. In this
work, we discuss the performance of this staggered multi-grid algorithm in four
dimensions. We also demonstrate that offloading some components of a
multi-shift solve to a multi-grid solver leads to a significant performance
improvement in an existing MILC spectrum workflow on the Summit and Selene
supercomputers.Comment: Submission to Proceedings of Lattice 2022: the 39th International
Symposium on Lattice Field Theory, Bonn, German