The nonperturbative functional renormalization group and its applications

N Dupuis, L Canet, A Eichhorn, W Metzner… - Physics Reports, 2021 - Elsevier
The renormalization group plays an essential role in many areas of physics, both
conceptually and as a practical tool to determine the long-distance low-energy properties of …

Long-range interacting quantum systems

N Defenu, T Donner, T Macrì, G Pagano, S Ruffo… - Reviews of Modern …, 2023 - APS
In this review recent investigations are summarized of many-body quantum systems with
long-range interactions, which are currently realized in Rydberg atom arrays, dipolar …

Interplay of spin waves and vortices in the two-dimensional XY model at small vortex-core energy

I Maccari, N Defenu, L Benfatto, C Castellani, T Enss - Physical Review B, 2020 - APS
The Berezinskii-Kosterlitz-Thouless (BKT) mechanism describes universal vortex unbinding
in many two-dimensional systems, including the paradigmatic XY model. However, most of …

Nonperturbative functional renormalization-group approach to the sine-Gordon model and the Lukyanov-Zamolodchikov conjecture

R Daviet, N Dupuis - Physical Review Letters, 2019 - APS
We study the quantum sine-Gordon model within a nonperturbative functional
renormalization-group approach (FRG). This approach is benchmarked by comparing our …

Nonperturbative renormalization group treatment of amplitude fluctuations for| φ| 4 topological phase transitions

N Defenu, A Trombettoni, I Nándori, T Enss - Physical Review B, 2017 - APS
The study of the Berezinskii-Kosterlitz-Thouless transition in two-dimensional| φ| 4 models
can be performed in several representations, and the amplitude-phase (AP) Madelung …

[HTML][HTML] Topological phase transitions in four dimensions

N Defenu, A Trombettoni, D Zappalà - Nuclear Physics B, 2021 - Elsevier
We show that four-dimensional systems may exhibit a topological phase transition
analogous to the well-known Berezinskii-Kosterlitz-Thouless vortex unbinding transition in …

LonTI Lectures on Sine-Gordon and Thirring

A Torrielli - arxiv preprint arxiv:2211.01186, 2022 - arxiv.org
arxiv:2211.01186v1 [hep-th] 2 Nov 2022 Page 1 DMUS-MP-22/20 LonTI Lectures on Sine-Gordon
and Thirring Alessandro Torrielli1 Department of Mathematics, School of Mathematics and …

Exploring the θ-vacuum structure in the functional renormalization group approach

K Fukushima, T Shimazaki, Y Tanizaki - Journal of High Energy Physics, 2022 - Springer
A bstract We investigate the θ-vacuum structure and the't Hooft anomaly at θ= π in a simple
quantum mechanical system on S 1 to scrutinize the applicability of the functional …

Renormalization group flows and fixed points for a scalar field in curved space with nonminimal coupling

BS Merzlikin, IL Shapiro, A Wipf, O Zanusso - Physical Review D, 2017 - APS
Using covariant methods, we construct and explore the Wetterich equation for a nonminimal
coupling F (ϕ) R of a quantized scalar field to the Ricci scalar of a prescribed curved space …

Exact renormalization group and Sine Gordon theory

P Oak, B Sathiapalan - Journal of High Energy Physics, 2017 - Springer
A bstract The exact renormalization group is used to study the RG flow of quantities in field
theories. The basic idea is to write an evolution operator for the flow and evaluate it in …