Article
Physics, Multidisciplinary
Dimitrios Bachtis, Gert Aarts, Francesco Di Renzo, Biagio Lucini
Summary: In this paper, we propose a method of inverse renormalization group transformations within the context of quantum field theory. This method can produce the appropriate critical fixed point structure, avoid the critical slowing down effect, and extract critical exponents. We also discuss the general applicability of this method and its insights into the structure of the renormalization group.
PHYSICAL REVIEW LETTERS
(2022)
Review
Physics, Multidisciplinary
N. Dupuis, L. Canet, A. Eichhorn, W. Metzner, J. M. Pawlowski, M. Tissier, N. Wschebor
Summary: The renormalization group is crucial in physics for determining the low-energy properties of systems and searching for ultraviolet completions. The nonperturbative functional renormalization group (FRG) method is a modern implementation of Wilson's RG, providing a framework to study models with correlated degrees of freedom over long distances. It is based on an exact functional flow equation and has applications in various fields of physics.
PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS
(2021)
Article
Astronomy & Astrophysics
Stanislaw D. Glazek
Summary: An exact computation of effective Hamiltonians for a basic model from the Yukawa theory was presented, showing that physical fermions are eigenstates of the effective Hamiltonians dressed with effective bosons. The study also illustrated the method of computing effective Hamiltonians for realistic theories using the renormalization group procedure and demonstrated how the perturbative expansion and Tamm-Dancoff approximation increase in accuracy along the evolution of the RGPEP.
Article
Astronomy & Astrophysics
Jing Shu, Ming-Lei Xiao, Yu-Hui Zheng
Summary: We construct a general partial wave amplitude basis for N -> M scattering, using Lorentz invariant Poincare ' Clebsch-Gordan coefficients expressed in terms of spinor-helicity variables. The inner product of these coefficients is defined, allowing for the conversion of on-shell phase space integration into an algebraic problem. We also develop a technique for partial wave expansions of arbitrary amplitudes, including those with infrared divergence. These methods are applied to computing the anomalous dimension matrix for general effective operators, obtaining unitarity cuts for loop amplitudes with an arbitrary number of external particles via partial wave expansion.
Article
Astronomy & Astrophysics
Cristobal Laporte, Nora Locht, Antonio D. Pereira, Frank Saueressig
Summary: Wetterich's equation is a powerful tool for studying the existence and universality of renormalization group fixed points with quantum scale invariance. A new approximation scheme is developed by projecting the functional renormalization group equation onto functions of the kinetic term. This projection reveals a new universality class with a unique spectrum of stability coefficients for scalars and gauge fields. The implications of these findings for asymptotically safe gravity-matter systems are discussed.
Article
Physics, Multidisciplinary
M. A. Green, J. W. Moffat
Summary: Renormalization group methods are used in a finite, nonlocal quantum field theory to address issues in scalar field theory. The triviality problem, Higgs boson mass hierarchy problem, and vacuum stability are not problems in this theory. The scalar Higgs field does not have a Landau pole.
EUROPEAN PHYSICAL JOURNAL PLUS
(2021)
Article
Physics, Particles & Fields
Daisuke Kadoh, Hideaki Oba, Shinji Takeda
Summary: In this research, we propose a second renormalization group (SRG) method based on the triad representation of tensor networks. The SRG method improves the decomposition and isometric preparation of the triad tensor, taking into account the influence of environment tensors. Numerical results obtained in the classical Ising model on the two-dimensional square lattice show good accuracy with a fixed computational time.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Aneesh Manohar, Emily Nardoni
Summary: In this study, effective field theory (EFT) methods were used to compute the renormalization group improved effective potential for theories with a large mass hierarchy. The method allowed for systematic expansion in powers of mass ratio and summation of large logarithms of mass ratios using renormalization group evolution. The comparison of effective potentials computed using EFT and the effective potential of EFT was explained, and the method did not have a Goldstone boson infrared divergence problem.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Astronomy & Astrophysics
Marzieh Akbari Ahmadmahmoudi, Ehsan Bavarsad
Summary: The induced one-loop energy-momentum tensor of a massive complex scalar field in the presence of a uniform electric field on the two-dimensional de Sitter spacetime was studied in the framework of nonperturbative quantum electrodynamics. Coupling the scalar field directly to the Ricci scalar curvature with an arbitrary dimensionless nonminimal coupling constant was considered, and the trace anomaly of the induced energy-momentum tensor was evaluated. Results for the induced energy-momentum tensor and trace anomaly in the zero electric field case were shown to be consistent with existing literature, and the nonperturbative, regularized, one-loop effective Lagrangian of scalar QED in dS(2) was constructed from the induced energy-momentum tensor.
Article
Physics, Nuclear
M. Ebert, H-W Hammer, A. Rusetsky
Summary: We discuss an alternative scheme for effective range corrections in pionless effective field theory, which shows good convergence for several model potentials.
EUROPEAN PHYSICAL JOURNAL A
(2021)
Article
Astronomy & Astrophysics
Jose Gaite
Summary: This article compares various formulations of the exact renormalization group and focuses on the renormalization of the lambda phi 4 theory in three dimensions. The results show that different methods yield good results with only small non-universal differences.
Article
Physics, Fluids & Plasmas
Matteo Paoluzzi
Summary: This article examines the role of nonequilibrium terms in active field theories in describing active phase separation, particularly at critical points. Despite their irrelevance at the critical point, these terms still contribute to nontrivial scaling of the entropy production rate.
Article
Computer Science, Interdisciplinary Applications
Thomas Deppisch, Florian Herren
Summary: RGE++ is a flexible, template-based C++ library for solving renormalisation group equations, with implementations available for the Standard Model, minimal supersymmetric extension of the Standard Model, two-Higgs-doublet models, and right-handed neutrino extensions. It provides numerical solutions using Eigen3 and odeint, as well as templates for additional models.
COMPUTER PHYSICS COMMUNICATIONS
(2022)
Article
Physics, Particles & Fields
Min-Seok Seo
Summary: This study investigates the conditions for the information paradox in quasi-dS space and its relation to the dS swampland conjecture.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Physics, Multidisciplinary
Jean-Paul Blaizot, Jan M. Pawlowski, Urko Reinosa
Summary: This study combines two non-perturbative approaches, the 2PI action and fRG, to develop new approximations for strongly coupled systems. By exploiting exact 2PI relations, the infinite hierarchy of fRG equations is truncated with two exact conditions. This transformation offers new ways to solve the equations practically and provides insights on renormalization, potentially leading to new approximation schemes and truncation schemes beyond existing methods.
