Mon·Dec 12, 2022Monday·December 12, 2022

1. 01*

   Overcoming exponential volume scaling in quantum simulations of lattice gauge theories

   Christopher F. Kane🇺🇸 · Dorota M. Grabowska🇨🇭 · Benjamin Nachman🇺🇸 · Christian W. Bauer🇺🇸

   Real-time evolution of quantum field theories using classical computers requires resources that scale exponentially with the number of lattice sites. Because of a fundamentally different computational strategy, quantum computers can in principle be used to perform detailed studies of these dynamics from first principles. Before performing such calculations, it is important to ensure that the quantum algorithms used do not have a cost that scales exponentially with the volume. In these proceedings, we present an interesting test case: a formulation of a compact U(1) gauge theory in 2+1 dimensions free of gauge redundancies. A naive implementation onto a quantum circuit has a gate count that scales exponentially with the volume. We discuss how to break this exponential scaling by performing an operator redefinition that reduces the non-locality of the Hamiltonian. While we study only one theory as a test case, it is possible that the exponential gate scaling will persist for formulations of other gauge theories, including non-Abelian theories in higher dimensions.

   hep-latquant-phPoS(2023)·2 citations
2. 02*

   Isospin-breaking corrections to light leptonic decays in lattice QCD+QED at the physical point

   Peter Boyle🇺🇸 · Matteo Di Carlo🇬🇧 · Felix Erben🇬🇧 · Vera Gülpers🇬🇧 · Maxwell T. Hansen🇬🇧 · Tim Harris🇬🇧 · Nils Hermansson-Truedsson🇨🇭 · Raoul Hodgson🇬🇧 · Andreas Jüttner🇬🇧 · Fionn Ó hÓgáin🇬🇧 · Antonin Portelli🇬🇧 · James Richings🇬🇧 · Andrew Z. N. Yong🇬🇧

   We report on the physical-point RBC/UKQCD calculation of the leading isospin-breaking corrections to light-meson leptonic decays. This is highly relevant for future precision tests in the flavour physics sector, in particular the first-row unitarity of the Cabibbo-Kobayashi-Maskawa matrix containing the elements $V_{us}$ and $V_{ud}$. The simulations were performed using Domain-Wall fermions for $2+1$ flavours, and with isospin-breaking effects included perturbatively in the path integral through order $\alpha$ and $(m_u-m_d)/{\Lambda }_{\mathrm{QCD}}$. We use QED${}_{\mathrm{L}}$ for the inclusion of electromagnetism, and discuss here the non-locality of this prescription which has significant impact on the infinite-volume extrapolation.

   hep-lathep-phPoS(2023)·3 citations
3. 03*

   Charmonium-like states with $J^P=1^{+}$ and isospin 1

   Mitja Sadl🇸🇮 · Sara Collins🇩🇪 · M. Padmanath🇩🇪 · Sasa Prelovsek🇸🇮

   Many mesons with properties incompatible with a $\bar{c}c$ structure have already been discovered, e.g. the $Z_c$ mesons with isospin 1. We investigate the spectrum of exotic charmonium-like mesons using lattice QCD. The focus is on $\bar{c}c\bar{q}q$ states with $J^{PC}=1^{+\pm }$ and isospin 1. This is the first study of four-quark states with these quantum numbers, a non-zero total momentum and two different lattice volumes. We extract the energy levels and determine the scattering length for $D{\bar{D}}^{\ast }$ scattering close to the threshold using Lüscher's formalism. Our preliminary results show that the energy shifts for eigenstates dominated by $D{\bar{D}}^{\ast }$ are very small in the $1^{++}$ channel and consistent with zero in the $1^{+-}$ channel.

   hep-lathep-phPoS(2023)·2 citations
4. 04*

   Open Science in Lattice Gauge Theory community

   Andreas Athenodorou🇨🇾 · Ed Bennett🇬🇧 · Julian Lenz🇬🇧 · Elli Papadopoullou🇬🇷

   Open science aims to make scientific research processes, tools and results accessible to all scientific communities, creating trust in science and enabling digital competences to be realized in research, leading to increased innovation. It provides standard and transparent pathways to conducting research and fosters best practices for collecting, analysing, preserving, sharing and reusing data, software, workflows and other outputs through collaborative networks. Open Science appears to be becoming the norm with its applications spanning throughout the whole research cycle of a project. The importance of making Open Science a reality is nowadays reflected in funding policies, research infrastructure and politics. In these proceedings we present the basic Open Science principles explaining briefly best practices for materialising Open Science. Subsequently, we present the results of the landscaping survey of Open Science in the Lattice Gauge Theories community. Finally, we provide directions in which the Lattice Gauge Theory community could move in order to enhance Openness and FAIRness (Findability, Accessibility, Interoperability, Reusability) in Science.

   hep-latphysics.soc-phPoS(2023)·7 citations
5. 05*

   BUQEYE Guide to Projection-Based Emulators in Nuclear Physics

   C. Drischler🇺🇸 · J.A. Melendez🇺🇸 · R.J. Furnstahl🇺🇸 · A.J. Garcia🇺🇸 · Xilin Zhang🇺🇸

   The BUQEYE collaboration (Bayesian Uncertainty Quantification: Errors in Your EFT) presents a pedagogical introduction to projection-based, reduced-order emulators for applications in low-energy nuclear physics. The term emulator refers here to a fast surrogate model capable of reliably approximating high-fidelity models. As the general tools employed by these emulators are not yet well-known in the nuclear physics community, we discuss variational and Galerkin projection methods, emphasize the benefits of offline-online decompositions, and explore how these concepts lead to emulators for bound and scattering systems that enable fast & accurate calculations using many different model parameter sets. We also point to future extensions and applications of these emulators for nuclear physics, guided by the mature field of model (order) reduction. All examples discussed here and more are available as interactive, open-source Python code so that practitioners can readily adapt projection-based emulators for their own work.

   ↳ nucl-thhep-lathep-phphysics.data-anFront.in Phys.(2022)·49 citations
6. 06*

   Simulating first-order phase transition with hierarchical autoregressive networks

   Piotr Białas🇵🇱 · Paulina Czarnota · Piotr Korcyl🇵🇱 · Tomasz Stebel🇵🇱

   We apply the Hierarchical Autoregressive Neural (HAN) network sampling algorithm to the two-dimensional $Q$-state Potts model and perform simulations around the phase transition at $Q=12$. We quantify the performance of the approach in the vicinity of the first-order phase transition and compare it with that of the Wolff cluster algorithm. We find a significant improvement as far as the statistical uncertainty is concerned at a similar numerical effort. In order to efficiently train large neural networks we introduce the technique of pre-training. It allows to train some neural networks using smaller system sizes and then employing them as starting configurations for larger system sizes. This is possible due to the recursive construction of our hierarchical approach. Our results serve as a demonstration of the performance of the hierarchical approach for systems exhibiting bimodal distributions. Additionally, we provide estimates of the free energy and entropy in the vicinity of the phase transition with statistical uncertainties of the order of $10^{-7}$ for the former and $10^{-3}$ for the latter based on a statistics of $10^6$ configurations.

   ↳ cond-mat.stat-mechcond-mat.dis-nnhep-latstat.MLPRE(2023)·7 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.