Tootfinder

Second-order renormalized Hamiltonian of Yukawa theory
Kamil Serafin, Carter M. Gustin, Peter J. Love
https://arxiv.org/abs/2508.02972 https://arxiv.org/pd…

Second-order renormalized Hamiltonian of Yukawa theory
Using the renormalization group procedure for effective particles (RGPEP) we calculate the effective Hamiltonians in the theory of a fermion field coupled to a scalar field via the Yukawa interaction. The theory is renormalized by the addition of counterterms. Necessary counterterms are determined by computing matrix elements of the effective Hamiltonian. All calculations are performed up to the second order in the expansion in powers of the coupling constant. Renormalized effective Hamiltonian…

Efter 50 år på den här planeten är jag förvånad över att människan fortfarande inte verkar vilja dela den med någon annan art. Vi trycker undan djur och växter alltmer, många av dem till den grad att de utrotas helt. En del göms undan i industrier där vi utvinner "nytta" och "produkter" – men utan att beblanda oss med dem. Bina får allt svårare att pollinera, korna får inte beta på sina ängar, renarna tvingas gå andra vägar när vi spränger hål i berget.
Är det verkli…

Non-Trivial Renormalization of Spin-Boson Models with Supercritical Form Factors
Marco Falconi, Benjamin Hinrichs, Javier Valent\'in Mart\'in
https://arxiv.org/abs/2508.00805

Non-Trivial Renormalization of Spin-Boson Models with Supercritical Form Factors
In this paper we construct the non-trivial, renormalized Hamiltonian for a class of spin-boson models with supercritical form factors, including the one describing the Weisskopf-Wigner spontaneous emission. The renormalization is performed through both a self-energy and mass renormalization, in the so-called Hamiltonian formalism of constructive quantum field theory, implemented by a non-unitary dressing transformation. This solves the problem of triviality for unitarily-renormalized supercriti…

Two-loop renormalisation of quark and gluon fields in the SMEFT in the on-shell scheme
Claude Duhr, Giuseppe Ventura, Eleni Vryonidou
https://arxiv.org/abs/2508.04500 https://…

Two-loop renormalisation of quark and gluon fields in the SMEFT in the on-shell scheme
We compute the contributions of CP-conserving dimension-six SMEFT operators to the two-loop renormalisation constants of quark and gluon fields in the on-shell scheme. Specifically, we consider the top-quark chromomagnetic operator and the triple gluon operator. We also compute the contribution of four-quark operators to the gluon renormalisation constant and discuss the implications for the running of the strong coupling constant.

Hierarchical community detection via maximum entropy partitions and the renormalization group
Jorge Martinez Armas
https://arxiv.org/abs/2508.04034 https://

Hierarchical community detection via maximum entropy partitions and the renormalization group
Identifying meaningful structure across multiple scales remains a central challenge in network science. We introduce Hierarchical Clustering Entropy (HCE), a general and model-agnostic framework for detecting informative levels in hierarchical community structures. Unlike existing approaches, HCE operates directly on dendrograms without relying on edge-level statistics. It selects resolution levels that maximize a principled trade-off between the entropy of the community size distribution and t…

Renormalization-Free Galaxy Bias in Unified Lagrangian Perturbation Theory
Naonori Sugiyama
https://arxiv.org/abs/2509.04142 https://arxiv.org/pdf/2509.041…

Renormalization-Free Galaxy Bias in Unified Lagrangian Perturbation Theory
We present a renormalization-free framework for modeling galaxy bias based on Unified Lagrangian Perturbation Theory (ULPT). In this approach, the biased density fluctuation is built solely from Galileon-type operators associated with the intrinsic nonlinear growth of dark matter. This ensures the bias expansion is well defined at the field level, automatically satisfies statistical conditions of vanishing ensemble and volume averages, and removes the need for ad hoc renormalization. We derive …

Structure of renormalization constants for theories with multiple couplings in the MS-like subtraction schemes
Gleb Kovyrshin, Nikolai Meshcheriakov, Victoria Shatalova, Konstantin Stepanyantz
https://arxiv.org/abs/2509.03437

Structure of renormalization constants for theories with multiple couplings in the MS-like subtraction schemes
For theories with multiple couplings we construct simple expressions for the four-dimensional (or, in general, integer-dimensional) renormalization constants assuming that all divergences are logarithmical. These expressions allow relating all coefficients at $\varepsilon$-poles, logarithms, and (if exist) mixed terms to the coefficients of the renormalization group functions in any order of the perturbation theory for MS-like renormalization prescriptions. The result admits such a formulation …

Renormalization group flows in area-metric gravity
Johanna Borissova, Bianca Dittrich, Astrid Eichhorn, Marc Schiffer
https://arxiv.org/abs/2507.02034 http…

Renormalization group flows in area-metric gravity
We put forward the first analysis of renormalization group flows in an area-metric theory, motivated by spin-foam quantum gravity. Area-metric gravity contains the well-known length-metric degrees of freedom of standard gravity as well as additional shape-mismatching degrees of freedom. To be phenomenologically viable, the shape-mismatching degrees of freedom have to decouple under the renormalization group flow towards lower scales. We test this scenario by calculating the renormalization grou…

Functional renormalization group study of rho condensate at a finite isospin chemical potential in the quark meson model
Mohammed Osman, Defu Hou, Wentao Wang, Hui Zhang
https://arxiv.org/abs/2508.02745

Functional renormalization group study of rho condensate at a finite isospin chemical potential in the quark meson model
We investigate the effect of an isospin chemical potential ($μ_{I}$) within the quark-meson model, which approximates quantum chromodynamics (QCD) by modeling low energy phenomena such as chiral symmetry breaking and phase structure under varying conditions of temperature and chemical potential. Using the functional renormalization group (FRG) flow equations, we calculate the phase diagram in the chiral limit within the two-flavor quark-meson model in a finite $μ_{I}$ with $ρ$ vector meson i…

Renormalization of generalized spin--boson models with critical ultraviolet divergences
Benjamin Alvarez, Sascha Lill, Davide Lonigro, Javier Valent\'in Mart\'in
https://arxiv.org/abs/2508.00803

Renormalization of generalized spin--boson models with critical ultraviolet divergences
We provide a rigorous construction of generalized spin--boson models with commuting transition matrices and form factors exhibiting critical ultraviolet (UV) divergences. That is, we cover all divergences where a self-energy renormalization, but no non-Fock representation, is required. Our method is based on a direct definition of the renormalized Hamiltonian on a sufficiently large test domain, followed by a Friedrichs extension. We then prove that this Hamiltonian coincides with the one obtai…