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Related papers: Two-Loop Fermionic Integrals in Perturbation Theor…

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Several Wilson loops on several lattice sizes are computed in Perturbation Theory via a stochastic method. Applications include: Renormalons, the Mass Term in Heavy Quark Effective Theory and (possibly) the beta-function.

High Energy Physics - Lattice · Physics 2015-06-25 G. Burgio , F. Di Renzo , L. Scorzato , M. Pepe

We explore the properties of two-point cosmic propagators when Perturbation Theory (PT) loop corrections are consistently taken into account. We show in particular how the interpolation scheme proposed in arXiv:1112.3895 can be explicitly…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-15 Francis Bernardeau , Atsushi Taruya , Takahiro Nishimichi

A unified formulation of one-loop tensor integrals is proposed for systematical calculations of finite volume corrections. It is shown that decomposition of the one-loop tensor integrals into a series of tensors accompanied by tensor…

High Energy Physics - Phenomenology · Physics 2022-12-28 Ze-Rui Liang , De-Liang Yao

A statistical inference method is developed and tested for pairwise interacting systems whose degrees of freedom are continuous angular variables, such as planar spins in magnetic systems or wave phases in optics and acoustics. We…

Statistical Mechanics · Physics 2015-06-15 P. Tyagi , A. Pagnani , F. Antenucci , M. Ibáñez Berganza , L. Leuzzi

Quantum simulators have the exciting prospect of giving access to real-time dynamics of lattice gauge theories, in particular in regimes that are difficult to compute on classical computers. Future progress towards scalable quantum…

Quantum Gases · Physics 2018-08-21 T. V. Zache , F. Hebenstreit , F. Jendrzejewski , M. K. Oberthaler , J. Berges , P. Hauke

We determine the master integrals for vertex and propagator diagrams that appear in effective field theories containing heavy fields. The integrals involve at least one heavy line, and the standard lines include an arbitrary mass scale. The…

High Energy Physics - Phenomenology · Physics 2022-01-19 B. Assi , B. A. Kniehl , A. I. Onishchenko

We calculate Wilson loops of various sizes up to loop order $n=20$ for lattice sizes of $L^4 (L=4, 6, 8, 12)$ using the technique of Numerical Stochastic Perturbation Theory in quenched QCD. This allows to investigate the behaviour of the…

High Energy Physics - Lattice · Physics 2010-11-05 E. -M. Ilgenfritz , Y. Nakamura , H. Perlt , P. E. L. Rakow , G. Schierholz , A. Schiller

We present an update on Numerical Stochastic Perturbation Theory projects for Lattice QCD, which are by now run on apeNEXT. As a first issue, we discuss a strategy to tackle finite size effects which can be quite sizeable in the computation…

High Energy Physics - Lattice · Physics 2009-04-14 Francesco Di Renzo , Luigi Scorzato , Christian Torrero

We show that the problem of solving recurrence relations for L-loop (R+1)-point Feynman integrals within the method of integration by parts is equivalent to the corresponding problem for (L+R)-loop vacuum or (L+R-1)-loop propagator-type…

High Energy Physics - Phenomenology · Physics 2009-10-31 P. A. Baikov , V. A. Smirnov

We discuss the computational complexity of the perturbative evaluation of scattering amplitudes, both by the Caravaglios-Moretti algorithm and by direct evaluation of the individual diagrams. For a self-interacting scalar theory, we…

High Energy Physics - Phenomenology · Physics 2009-11-10 Ernst van Eijk , Ronald Kleiss , Achilleas Lazopoulos

We briefly sketch the methods for a numerically stable evaluation of tensor one-loop integrals that have been used in the calculation of the complete electroweak one-loop corrections to $\Pep\Pem\to4 $fermions. In particular, the…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Denner , S. Dittmaier

Our aim is to compute the lower moments of the unpolarized and polarized deep-inelastic structure functions of the nucleon on the lattice. The theoretical basis of the calculation is the operator product expansion. To construct operators…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , R. Horsley , E. -M. Ilgenfritz , H. Perlt , P. Rakow , G. Schierholz , A. Schiller

We study the self energies of all particles which appear in a lattice regularization of supersymmetric QCD (${\cal N}=1$). We compute, perturbatively to one-loop, the relevant two-point Green's functions using both the dimensional and the…

High Energy Physics - Lattice · Physics 2017-04-05 M. Costa , H. Panagopoulos

We investigate the attractive Fermi polaron problem in two dimensions using non-perturbative Monte Carlo simulations. We introduce a new Monte Carlo algorithm called the impurity lattice Monte Carlo method. This algorithm samples the path…

Quantum Gases · Physics 2015-10-29 Shahin Bour , Dean Lee , H. -W. Hammer , Ulf-G. Meißner

SU(2) gauge theory with two fermions transforming under the adjoint representation may appear conformal or almost conformal in the infrared, and is one of the candidate theories for building models for technicolor. Early lattice Monte Carlo…

High Energy Physics - Lattice · Physics 2015-05-20 Tuomas Karavirta , Anne Mykkanen , Jarno Rantaharju , Kari Rummukainen , Kimmo Tuominen

We put forward several information-theoretic measures for analyzing the uncertainty of fermionic phase-space distributions using the theory of supernumbers. In contrast to the bosonic case, the anticommuting nature of Grassmann variables…

Quantum Physics · Physics 2025-09-26 Nicolas J. Cerf , Tobias Haas

The lattice formulation provides a way to regularize, define and compute the Path Integral in a Quantum Field Theory. In this paper we review the theoretical foundations and the most basic algorithms required to implement a typical lattice…

High Energy Physics - Lattice · Physics 2009-11-11 Massimo Di Pierro

Path-integral expressions for one-particle propagators in scalar and fermionic field theories are derived, for arbitrary mass. This establishes a direct connection between field theory and specific classical point-particle models. The role…

High Energy Physics - Theory · Physics 2010-11-22 J. W. van Holten

An algorithm for calculating two-loop propagator type Feynman diagrams with arbitrary masses and external momentum is proposed. Recurrence relations allowing to express any scalar integral in terms of basic integrals are given. A minimal…

High Energy Physics - Phenomenology · Physics 2009-10-30 O. V. Tarasov

This review gives an overview on the research of algorithms for dynamical fermions used in large scale lattice QCD simulations. First a short overview on the state-of-the-art of ensemble generation at the physical point is given. Followed…

High Energy Physics - Lattice · Physics 2024-02-20 Jacob Finkenrath