Mon·Oct 10, 2022Monday·October 10, 2022

1. 01*

   Stochastic normalizing flows for lattice field theory

   Michele Caselle🇮🇹 · Elia Cellini🇮🇹 · Alessandro Nada🇮🇹 · Marco Panero🇮🇹

   Stochastic normalizing flows are a class of deep generative models that combine normalizing flows with Monte Carlo updates and can be used in lattice field theory to sample from Boltzmann distributions. In this proceeding, we outline the construction of these hybrid algorithms, pointing out that the theoretical background can be related to Jarzynski's equality, a non-equilibrium statistical mechanics theorem that has been successfully used to compute free energy in lattice field theory. We conclude with examples of applications to the two-dimensional ${\varphi }^4$ field theory.

   hep-latPoS(2023)·13 citations
2. 02*

   Confinement in $QCD$: novelties

   Adriano Di Giacomo🇮🇹

   We report on recent progress in understanding confinement of colour in $QCD$ as dual superconductivity of the vacuum. A gauge invariant version of the creation operator of monopoles is constructed whose vacuum expectation value is the order parameter. This order parameter is gauge-invariant from scratch, has no infrared divergences, is finite in the confined phase and vanishes in the deconfined phase. A natural explanation also emerges of why the electric field lines in the flux tubes keep no memory of the colour orientation of the condensing monopoles. A further by-product is that the order parameter can be traded with the two-point vacuum parallel correlator of the chromo-electric field.

   hep-lathep-phhep-thNucl.Part.Phys.Proc.(2023)·0 citations
3. 03*

   Fine-Tuning of the Yukawa and Quartic Couplings in Supersymmetric QCD

   M. Costa🇨🇾 · H. Herodotou🇨🇾 · H. Panagopoulos🇨🇾

   In this work, we investigate the fine tuning of parameters in $\mathcal{N}=1$ Supersymmetric QCD, discretized on a Euclidean lattice. Specifically, we study the renormalization of the Yukawa (gluino-quark-squark interactions) and the quartic (four-squark interactions) couplings. At the quantum level, these interactions suffer from mixing with other operators which have the same transformation properties. We exploit the symmetries of the action, such as charge conjugation and parity, in order to reduce the allowed mixing patterns. To deduce the renormalizations and the mixing coefficients we compute, perturbatively to one-loop and to the lowest order in the lattice spacing, the relevant three-point and four-point Green's functions using both dimensional and lattice regularizations. Our lattice formulation involves the Wilson discretization for the gluino and quark fields; for gluons we employ the Wilson gauge action; for scalar fields (squarks) we use naïve discretization. We obtain analytic expressions for the renormalization and mixing coefficients of the Yukawa couplings; they are functions of the number of colors $N_c$, the gauge parameter $\alpha$, and the gauge coupling $g$. Furthermore, preliminary results on the quartic couplings are also presented.

   hep-latPoS(2023)·4 citations
4. 04*

   Investigation of a candidate spin-$\frac{1}{2}$ hidden-charm triple strange pentaquark state $P_{csss}$

   K. Azizi🇮🇷 · Y. Sarac🇹🇷 · H. Sundu🇹🇷

   A candidate triple strange pentaquark state, $P_{csss}$, is investigated through its strong decay channel $P_{csss}\to {\Omega }^{-}J/\psi$. To calculate the relevant strong coupling constants, two possible interpolating currents with spin-parity $J^P={\frac{1}{2}}^{-}$ are used. Though the chosen currents for the state under consideration have spin-parity quantum numbers $J^P={\frac{1}{2}}^{-}$, they couple to both the positive and negative parity states simultaneously and the corresponding decay widths are obtained for both parities. These widths are obtained as $\Gamma (P_{csss}\to J/\psi {\Omega }^{-})=201.4\pm 82.5\mathrm{MeV}$ for the negative and $\Gamma ({\tilde{P}}_{csss}\to J/\psi {\Omega }^{-})=316.4\pm 107.8\mathrm{MeV}$ for the positive parity state when the first current is used. For the second current, we obtain $\Gamma (P_{csss}\to J/\psi {\Omega }^{-})=252.5\pm 116.7\mathrm{MeV}$ for the negative and $\Gamma ({\tilde{P}}_{csss}\to J/\psi {\Omega }^{-})=361.1\pm 98.4\mathrm{MeV}$ for the positive parity state. These results may provide insights into future experimental observations of such candidate states and help to distinguish and fix their properties.

   ↳ hep-phhep-exhep-latPRD(2023)·15 citations
5. 05*

   Towards a Quantum Simulation of Nonlinear Sigma Models with a Topological Term

   Jack Y. Araz🇬🇧 · Sebastian Schenk🇬🇧 · Michael Spannowsky🇬🇧

   We determine the mass gap of a two-dimensional $O(3)$ nonlinear sigma model augmented with a topological $\theta$-term using tensor network and digital quantum algorithms. As proof of principle, we consider the example $\theta =\pi$ and study its critical behaviour on a quantum simulator by examining the entanglement entropy of the ground state. We confirm that the quantum theory is massless in the strong-coupling regime, in agreement with analytical results. However, we also highlight the limitations of current quantum algorithms, designed for noisy intermediate-scale quantum devices, in the theory simulation at weak coupling. Finally, we compare the performance of our quantum algorithms to classical tensor network methods.

   ↳ quant-phhep-lathep-phhep-thPRA(2023)·19 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.