Mon·Sep 27, 2021Monday·September 27, 2021

1. 01*

   Gauge invariant input to neural network for path optimization method

   Yusuke Namekawa🇯🇵 · Kouji Kashiwa🇯🇵 · Akira Ohnishi🇯🇵 · Hayato Takase

   We investigate the efficiency of a gauge invariant input to a neural network for the path optimization method. While the path optimization with a completely gauge-fixed link-variable input has successfully tamed the sign problem in a simple gauge theory, the optimization does not work well when the gauge degrees of freedom remain. We propose to employ a gauge invariant input, such as plaquette, to overcome this problem. The efficiency of the gauge invariant input to the neural network is evaluated for the 2-dimensional $U(1)$ gauge theory with a complex coupling. The average phase factor is significantly enhanced by the path optimization with the plaquette input, indicating good control of the sign problem. It opens a possibility that the path optimization is available to complicated gauge theories, including Quantum Chromodynamics, in a realistic setup.

   hep-latcond-mat.dis-nnPRD(2022)·10 citations
2. 02*

   Quantum State Preparation for the Schwinger Model

   Giovanni Pederiva🇺🇸 · Alexei Bazavov🇺🇸 · Brandon Henke🇺🇸 · Leon Hostetler🇺🇸 · Dean Lee🇺🇸 · Huey-Wen Lin🇺🇸 · Andrea Shindler🇺🇸

   It is not possible, using standard lattice techniques in Euclidean space, to calculate the complete fermionic spectrum of a quantum field theory. Algorithms running on quantum computers have the potential to access the theory with real-time evolution, enabling a direct computation. As a testing ground we consider the 1 + 1-dimensional Schwinger model with the presence of a {\theta} term using a staggered fermions discretization. We study the convergence properties of two different algorithms - adiabatic evolution and the Quantum Approximate Optimization Algorithm - with an emphasis on their cost in terms of CNOT gates. This is crucial to understand the feasibility of these algorithms, because calculations on near-term quantum devices depend on their rapid convergence. We also propose a blocked algorithm that has the first indications of a better scaling behavior with the dimensionality of the problem.

   hep-latPoS(2022)·13 citations
3. 03*

   Study of a lattice 2-group gauge model

   Arkadiusz Bochniak🇵🇱 · Leszek Hadasz🇵🇱 · Piotr Korcyl🇵🇱 · Błażej Ruba🇵🇱

   Gauge theories admit a generalisation in which the gauge group is replaced by a finer algebraic structure, known as a 2-group. The first model of this type is a Topological Quantum Field Theory introduced by Yetter. We discuss a common generalisation of both the Yetter's model and Yang-Mills theory and in particular we focus on the lattice formulation of such model for finite 2-groups. In the second part we present a particular realization based on a 2-group constructed from ${\mathbb{Z}}_4$ groups. In the selected model, independent degrees of freedom are associated to both links and faces of a four-dimensional lattice and are subject to a certain constraint. We present the details of this construction, discuss the expected dynamics in different regions of phase space and show numerical results from Monte Carlo simulations corroborating these expectations.

   hep-latcond-mat.str-elhep-thPoS(2022)·2 citations
4. 04*

   Revealing pion and kaon structure via generalised parton distributions

   Khepani Raya🇨🇳 · Zhu-Fang Cui🇨🇳 · Lei Chang🇨🇳 · Jose-Manuel Morgado🇪🇸 · Craig D. Roberts🇨🇳 · Jose Rodriguez-Quintero🇪🇸

   Clear windows onto emergent hadron mass (EHM) and modulations thereof by Higgs boson interactions are provided by observable measures of pion and kaon structure, many of which are accessible via generalised parton distributions (GPDs). Beginning with algebraic GPD Ansaetze, constrained entirely by hadron-scale $\pi$ and $K$ valence-parton distribution functions (DFs), in whose forms both EHM and Higgs boson influences are manifest, numerous illustrations are provided. They include the properties of electromagnetic form factors, impact parameter space GPDs, gravitational form factors and associated pressure profiles, and the character and consequences of all-orders evolution. The analyses predict that mass-squared gravitational form factors are stiffer than electromagnetic form factors; reveal that $K$ pressure profiles are tighter than $\pi$ profiles, with both mesons sustaining near-core pressures at magnitudes similar to that expected at the core of neutron stars; deliver parameter-free predictions for $\pi$ and $K$ valence, glue, and sea GPDs at the resolving scale $\zeta =2$GeV; and predict that at this scale the fraction of meson mass-squared carried by glue and sea combined matches that lodged with the valence degrees-of-freedom, with a similar statement holding for mass-squared radii.

   ↳ hep-phhep-exhep-latnucl-ex+1CPC(2022)·83 citations
5. 05*

   Role of anomalous symmetry in 0-$\pi$ qubits

   I.L. Egusquiza🇪🇸 · A. Iñiguez🇪🇸 · E. Rico🇪🇸 · A. Villarino🇪🇸

   We present an exact full symmetry analysis of the 0-$\pi$ superconducting circuit. We identify points in control parameter space of enhanced anomalous symmetry, which imposes robust twofold degeneracy of its ground state, that is for all values of the energy parameters of the model. We show, both analytically and numerically, how this anomalous symmetry is maintained in the low-energy sector, thus providing us with a strong candidate for robust qubit engineering.

   ↳ quant-phcond-mat.supr-conhep-lathep-thPRB(2022)·4 citations
6. 06*

   Loop-Free Tensor Networks for High-Energy Physics

   S. Montangero🇮🇹 · E. Rico🇪🇸 · P. Silvi🇦🇹

   This brief review introduces the reader to tensor network methods, a powerful theoretical and numerical paradigm spawning from condensed matter physics and quantum information science and increasingly exploited in different fields of research, from artificial intelligence to quantum chemistry. Here, we specialise our presentation on the application of loop-free tensor network methods to the study of High-Energy Physics (HEP) problems and, in particular, to the study of lattice gauge theories where tensor networks can be applied in regimes where Monte Carlo methods are hindered by the sign problem.

   ↳ quant-phcond-mat.str-elhep-lathep-thPhil.Trans.A.Math.Phys.Eng.Sci.(2021)·25 citations
7. 07*

   An alternative scheme for effective range corrections in pionless EFT

   M. Ebert🇩🇪 · H.-W. Hammer🇩🇪 · A. Rusetsky🇩🇪

   We discuss an alternative scheme for including effective range corrections in pionless effective field theory. The standard approach treats range terms as perturbative insertions in the T -matrix. In a finite volume this scheme can lead to singular behavior close to the unperturbed energies. We consider an alternative scheme that resums the effective range but expands the spurious pole of the T -matrix created by this resummation. We test this alternative expansion for several model potentials and observe good convergence.

   ↳ hep-phhep-latnucl-thEPJA(2021)·16 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.