Name: 13th International Conference on the Exact Renormalization Group 2026 (ERG2026)
Start: 2026-09-01T00:00:00+01:00
End: 2026-09-05T23:00:00+01:00
Location: University of Sussex

13th International Conference on the Exact Renormalization Group 2026 (ERG2026)

from Tuesday, 1 September 2026 (00:00) to Saturday, 5 September 2026 (23:00)

Monday, 31 August 2026
Tuesday, 1 September 2026

09:00 Welcome
Welcome
09:00 - 09:30
Room: Large Lecture Theatre
09:30 Unified theory of interacting Dirac fermions in two dimensions, and the dark side of the Gross-Neveu model - Igor Herbut (Simon Fraser University)
Unified theory of interacting Dirac fermions in two dimensions, and the dark side of the Gross-Neveu model
- Igor Herbut (Simon Fraser University)
09:30 - 10:00
Room: Large Lecture Theatre Gapless Dirac fermions appear as low-energy excitations in many condensed matter systems of recent interest. They are often weakly interacting, as famously in graphene, but at stronger interactions they can also acquire a gap ("mass") and exhibit many ordered ground states by going through phase transitions at which gapless Dirac fermions play a crucial role. Prime example of this occurs in the Hubbard model on honeycomb lattice at half filling, which suffers a "relativistic Mott transition" from gapless semimetal to gapped insulator, believed to be observed recently in twisted multilayers. I will discuss the recent unification of all order parameters for Dirac systems in two dimensions based on large hidden orthogonal symmetry of free Dirac fermions. Interestingly, the unique interacting field theory that respects such an orthogonal symmetry turns out to be equivalent to the celebrated Gross-Neveu model. I will argue that, in spite of recently turning 50, this model still has a large, unexplored, and surprisingly interesting region of its coupling constant. Recent analytical and numerical results relevant to this "dark side" of the Gross-Neveu model will be presented.
10:00 Towards First-Principles Functional Renormalization Group for Quantum Materials - Lennart Klebl (University of Würzburg)
Towards First-Principles Functional Renormalization Group for Quantum Materials
- Lennart Klebl (University of Würzburg)
10:00 - 10:30
Room: Large Lecture Theatre In this talk, I introduce the first open-source functional renormalization group (FRG) code for condensed matter systems: divERGe. The development of flexible and accessible computational frameworks is becoming increasingly important as modern condensed matter problems continue to grow in complexity, spanning from minimal theoretical models to realistic descriptions of quantum materials. divERGe is designed to bridge this gap by providing a versatile platform for implementing and applying FRG approaches across a broad range of systems. I will highlight the general structure of the code, its modular design, and key interface considerations that enable efficient adaptation to different physical problems and computational workflows. Particular emphasis will be placed on how divERGe facilitates studies beyond conventional single-band models, including multi-orbital and multi- sublattice systems, as well as applications incorporating fully first- principles-derived material parameters. This allows for a systematic investigation of competing electronic instabilities and emergent phases in increasingly realistic settings. The talk will further showcase several recent applications demonstrating the capabilities of the framework. Notable use cases include the prediction of unconventional chiral p/d-wave superconductivity in twisted bilayer WSe₂, the identification of nearly nodeless extended s-wave superconductivity in twisted bilayer SnSe₂, and the electronic origin of Pomeranchuk order in a Ti-based Kagome metal. These examples illustrate how modern FRG techniques can provide valuable insights into the mechanisms driving unconventional quantum phenomena in complex materials.
10:30 Coffee
Coffee
10:30 - 11:00
Room: Atrium
11:00 Superdiffusion and chaos from Bernoulli randomness on simple graphs - Nicolo Defenu
Superdiffusion and chaos from Bernoulli randomness on simple graphs
- Nicolo Defenu
11:00 - 11:30
Room: Large Lecture Theatre While universality on regular lattices is controlled by the Euclidean dimension, its fate on inhomogeneous structures has long remained an open question, with early work identifying the spectral dimension as the relevant parameter. In this talk, I will consider simple random graphs where long-range bonds are drawn from a Bernoulli distribution, so that the same bonds simultaneously generate superdiffusive transport and correlated quenched disorder — a situation beyond the conventional Harris and Weinrib–Halperin framework, where disorder perturbs a pre-existing clean theory. For the self-avoiding walk on such graphs, large-scale Monte Carlo simulations and a Gaussian-truncated field theory show that the long-range kinetic operator dominates under coarse-graining, restoring the clean superdiffusive Lévy universality class, yet through an irrelevance mechanism qualitatively different from the Weinrib–Halperin scenario. In contrast, in the single-particle spectral problem the same geometric randomness generates quantum-chaotic level statistics and drives a localization transition beyond the reach of Gaussian field theory, signalling the infrared relevance of higher Bernoulli cumulants. These results identify graph disorder as a distinct class of randomness, whose non-Gaussian statistics may give rise to novel universality classes.
11:30 FRG phase diagram and superconductivity from ab-initio models of twisted WSe2 - Laura Classen (Max-Planck-Institut for Solid State Research)
FRG phase diagram and superconductivity from ab-initio models of twisted WSe2
- Laura Classen (Max-Planck-Institut for Solid State Research)
11:30 - 12:00
Room: Large Lecture Theatre Moiré materials constitute a highly tunable platform to investigate strongly correlated phenomena. In recent experiments, superconductivity was observed in the moiré material twisted WSe2, which extends the material families of superconductors and promises to advance our understanding of this intricate many-body quantum state. Superconductivity in twisted WSe2 appears next to an interaction-induced insulator and is tunable via an external displacement field. We analyze the correlated electron phases in twisted bilayer WSe2 at hole filling -1 and twist angle 3.65 using functional renormalization group calculations and investigate the dependence on model input. The advantage of using functional renormalisation here is that it treats the different ordering tendencies on equal footing and can detect superconductivity from repulsive bare interactions. We compare the instabilities obtained from a continuum model with gate-screened Coulomb interaction and a three-orbital Wannier model with Hubbard interaction, which we derive from first principles. In both cases, we find a superconducting instability with a mixed d-wave singlet and p-wave triplet symmetry arising adjacent to inter-valley coherent spin density wave order in the phase diagram for varying displacement field and interaction strength. We argue that the pairing mechanism is consistent with inter-valley coherent spin fluctuations as pairing glue. We show that the size and critical temperatures of the pairing regime change depending on the model input, and we argue that the main difference comes from the range and quantum geometry entering the projected interaction. In particular, we obtain pairing down to zero displacement field from the Coulomb interaction within the continuum model, reconciling theory and experiment.
12:00 Lunch
Lunch
12:00 - 13:40
13:40 Parallel Session: Room 1
Room 1
13:40 - 15:00
Room: Large Lecture Theatre
Contributions

13:40 Landau damping and quantum criticality in Fermi systems from the Wilsonian RG perspective - Paweł Jakubczyk (Institute of Theoretical Physics, Faculty of Physics, University of Warsaw)

14:00 Quantum critical Dirac semimetals and finite-temperature effects - Mireia Tolosa-Simeón

14:20 From Bose glass to Many-Body Localization in a one-dimensional disordered Bose gas - Vincent Grison (Sorbonne Université)

14:40 Dynamics in quantum random-field systems: localization or activation? - Ivan Balog (Institute of Physics, Zagreb)
Parallel Session: Room 2
Room 2
13:40 - 15:00
Room: 155
Contributions

13:40 Strongly coupled four-fermion fixed points in four dimensions - Charlie Cresswell-Hogg

14:00 Chiral Lagrangian as a proxy for ASQG - Francesco Del Porro (Niels Bohr Institute)

14:20 Renormalizability and UV behavior of 5D gauge theories - Anca Preda (Lund University)

14:40 RG fixed points from outer automorphisms and goofy transformations - Andreas Trautner (CFTP, IST, University of Lisbon)
Parallel Session: Room 3
Room 3
13:40 - 15:00
Room: 144
Contributions

13:40 The $\theta$-vacuum from functional renormalisation - Yuepeng Guan (Jilin University)

14:00 Conformal Symmetry as an Organizing Principle for the Derivative Expansion - Gonzalo De Polsi

14:20 Modified Forward Scattering and Unitarity in Matter Chern-–Simons Theory - Max Uetrecht (TU Dortmund University)

14:40 New approach to OPE coefficients from the FRG - Félix Rose (LPTM, CY Cergy Paris Université)
15:00 Coffee
Coffee
15:00 - 15:30
Room: Atrium
15:30 Poster presentations: 1-min slide show
1-min slide show
15:30 - 16:00
Room: Large Lecture Theatre
Contributions

15:30 TBC - David Dullaway (University of Sussex)

15:31 Constructing UV-critical hypersurfaces using machine learning - Stijn Hennissen (Radboud University)

15:32 Resurgence in Ward–Schwinger–Dyson Equations for QED - Edwyn Tecedor (LPTHE - Sorbonne Université)

15:33 Many-body correlations in Floquet steady-states: Frequency-resolved renormalization group of the driven Anderson impurity - Dominik Chudy (RWTH Aachen University) Jan Herre (RWTH Aachen University)

15:34 Weyl Gauged Gravity - Fabrizio Chicconi (University of Pisa, INFN) Luca Parente (University of Pisa, INFN)

15:35 One symmetry, multiple avatars: U(1) in Asymptotically Safe Gravity - Juan Fernandez Molinero (Radboud University)

15:36 Multicritical fixed points from functional renormalisation - Iason Vakondios

15:37 Can the Radiation Era be Extended all the way to the Bang? - Vatsalya Vaibhav (University of Edinburgh)

15:38 Resurgence and FRG Perspectives in Strong-Field QED - Gabriel Weigert (Friedrich-Schiller-Universität Jena)

15:39 On the Structure of the Fermion Sector in the Asymptotically Safe Standard Model - Moritz Gessner (Universität Heidelberg)

15:40 Conformal Invariance Constraints in the Functional Renormalization Group - Jorge Ibañez (Universidad de la República (UdelaR))

15:41 Chiral Quantum Phase Transition in Moiré Dirac Materials at finite density - Ana García-Page (Max-Planck-Institut for Solid State Research)

15:43 Probing Conformal Windows with Perturbation Theory - Nahzaan Riyaz (University of Sussex)

15:44 Spatial Coarse-Graining Impedes the Ability to Classify Message-Passing Algorithms - Carter Goldman (University of Sussex)

15:45 Gauge-Invariant and Background-Indepedent Quantum Gravity - Paul Philip Sprenger (Institute for Theoretical Physics, Heidelberg University)

15:46 Universal Thermodynamics of Two-Dimensional Bose Gas: a Non-Perturbative Renormalization Group Approach - Yaniss Rabahi (PhLam laboratory)

15:47 On black-hole scalarization: strong breaking of black-hole uniqueness and constraints from asymptotically safe gravity - Lidia Marino (ITP-Heidelberg)

15:48 Scalar Matter in Lorentzian Quantum Gravity - Rowan Packer (University of Sussex)
16:00 Analytic results in Asymptotic Safety - Benjamin Knorr (Heidelberg University)
Analytic results in Asymptotic Safety
- Benjamin Knorr (Heidelberg University)
16:00 - 16:30
Room: Large Lecture Theatre I am presenting analytic results on momentum-dependent gravitational and gravity-matter correlation functions in Asymptotic Safety. I will discuss their complex-analytic structure, and results on scattering cross sections.
16:30 From Functional to Ricci Flows: Asymptotic Safety in Perturbation Theory - Yannick Kluth (University of Toronto)
From Functional to Ricci Flows: Asymptotic Safety in Perturbation Theory
- Yannick Kluth (University of Toronto)
16:30 - 17:00
Room: Large Lecture Theatre Evidence for the existence of a UV fixed point in quantum gravity is usually derived using the functional renormalization group. In this talk, I discuss how this fixed point can be found solely using perturbation theory, provided one adopts a suitable renormalization scheme that retains the relevant physics. While the FRG achieves this naturally, I will discuss alternative methods tailored to a perturbative formulation, such as modifications of minimal subtraction in dimensional regularization, or the Ricci flow in quantum gravity. Similarly to the FRG, these methods yield a one-loop fixed point in four-dimensional quantum gravity. I close by discussing the implications of these findings and the connection to FRG results.
17:00 Poster presentations
17:00 - 17:30
Room: Large Lecture Theatre
Contributions

17:00 Two-Component Bose Mixtures: Mean-Field Theory and Functional Renormalisation Group - Oskar Stachowiak

17:01 Critical behavior of isotropic magnets with screened dipolar interactions - Max Fornoville (Max Planck Institute for Solid State Research)

17:02 Negative diffusion in the Functional Renormalization Group flow for the Quark-Diquark Model - Johannes Pöplau

17:03 Self-consistent quark-meson spectral functions - Konrad Kockler (Institut für Theoretische Physik, Universitat Heidelberg)

17:04 Analytically continued FRG for dissipative open quantum systems - Patrick Niekamp (JLU Giessen)

17:05 Cosmology from asymptotically safe Proca theories - Carlos Pastor Marcos (Institute for Theoretical Physics (ITP), Heidelberg University)

17:06 Symmetry breaking in the Nambu-Jona-Lasinio Model using the FRG - Freddie Matthew King (University of Sussex)

17:07 Probability distribution of order parameter in O(N) models - Lovro Šaravanja (Institute for Physics)

17:08 Spontaneous symmetry breaking in a relativistic Yukawa theory with Luttinger fermions - Tim Lukas Eckert (FSU Jena)

17:09 Composite-field tree expansions of 1PI vertices - Oleksandr Sulyma

17:10 Scaling regimes of shallow water turbulence - Gregorio Tibone (Côte d'Azur University, INPHYNI)

17:11 Generative diffusion model with inverse renormalization group flows - Kanta Masuki (The University of Tokyo)

17:12 Mass scale hierarchies in a Yukawa model with Luttinger and Dirac fermions from self-organized criticality - Yunxin Ye (FSU Jena)

17:13 Non-perturbative news from the conformal window - Alvaro Pastor Gutierrez (RIKEN iTHEMS)

17:14 Non-Renormalization of $\pi_1$-Characters under Finite ERG Transformations on Multiply Connected Configuration Spaces - Taichi Tanaka (Nihon University)

17:15 A tale of scales in Asymptotically Safe Quantum Gravity - Francesco Ferrarin (University of Copenhagen, Niels Bohr Institute)

17:16 The moat regime under magnetic fields - Justin Mauldin (Goethe University Frankfurt)

17:17 Computing the Bubble Nucleation Rate with Functional Renormalisation Group Methods - Rory Phipps (University of Sussex)
17:30 Fish & Chips break
Fish & Chips break
17:30 - 18:00
Room: Atrium

18:00 Poster session
Poster session
18:00 - 21:00
Room: Atrium
Wednesday, 2 September 2026
09:00 Dense QCD and the moat regime - Fabian Rennecke (University of Giessen)
Dense QCD and the moat regime
- Fabian Rennecke (University of Giessen)
09:00 - 09:30
Room: Large Lecture Theatre QCD is expected to have a rich phase structure at finite density. However, owing to strong coupling and sign problems, only little is known from first principles. The functional renormalization group allows for direct access to dense QCD matter based on microscopic quark-gluon dynamics. Model studies suggest the existence of inhomogeneous/crystalline phases at large density. The moat regime, where the static energy of bosonic excitations is minimized at nonzero momentum, encodes spatial modulations in the system and is hence a precursor for such phases. After introducing QCD from an FRG perspective more generally, I discuss the physics of the moat regime and the possibilities for its experimental discovery through heavy-ion collisions.
09:30 Existence of IR fixed points in the QCD chiral transition - Gergely Fejos (Eötvös University Budapest)
Existence of IR fixed points in the QCD chiral transition
- Gergely Fejos (Eötvös University Budapest)
09:30 - 10:00
Room: Large Lecture Theatre I will review recent developments concerning the possibility of a second-order chiral transition in the zero quark mass limit. Within the local potential approximation, using a phi^6 truncation, fixed points are found spanning the entire range of flavour numbers. I will discuss potential problems with this ansatz and review how the approach could be extended to global fixed-point potentials. I will also briefly comment on the N_c = 2 scenario.
10:00 Gravitational Form Factors, Conformal Symmetry and the Conformal Window - Roman Zwicky (Edinburgh University)
Gravitational Form Factors, Conformal Symmetry and the Conformal Window
- Roman Zwicky (Edinburgh University)
10:00 - 10:30
Room: Large Lecture Theatre I will review gravitational form factors and their connection to the energy-momentum tensor, with emphasis on their pressure interpretation and conformal symmetry. I will then discuss the conformal window and some (old) open questions concerning the transition between conformal and chirally broken phases. If time permits, I will illustrate these ideas with applications to my own work, including the interpretation of the $\sigma$ meson as a dilaton—the pseudo-Goldstone boson associated with spontaneously broken conformal symmetry.
10:30 Coffee
Coffee
10:30 - 11:00
Room: Atrium
11:00 Gravity from Entropy - Ginestra Bianconi (Queen Mary University of London)
Gravity from Entropy
- Ginestra Bianconi (Queen Mary University of London)
11:00 - 11:30
Room: Large Lecture Theatre Gravity is derived from an entropic action coupling matter fields with geometry called Gravity from Entropy action [1]. The fundamental idea is to relate the metric of Lorentzian spacetime to a quantum operator, playing the role of a renormalizable effective density matrix and to describe the matter fields topologically, according to a Dirac-Kähler formalism, as the direct sum of a 0-form, a 1-form and a 2-form. While the geometry of spacetime is defined by its metric, the matter fields can be used to define an alternative metric, the metric induced by the matter fields and curvature. The proposed Gravity from Entropy (GfE) action is associated to a Lagrangian given by a novel geometric quantum relative entropy (GQRE) between the metric of spacetime and the metric induced by the matter fields and curvature which capture the entanglement between geometric degrees of freedom of spacetime. The modified Einstein equations obtained from this action reduce to the Einstein equations with zero cosmological constant in the regime of low coupling. By introducing the G-field, which acts as a set of Lagrangian multipliers, and interpreting it a physical and measurable field, the proposed entropic action reduces to a dressed Einstein-Hilbert action with an emergent positive cosmological constant only dependent on the G-field. The obtained equations of modified gravity remain second order in the metric and in the G-field. Interestingly the GfE action when calculated on Schwarzschild metric allows us to derive from first principles the area law for black holes with large Schwarzschild radius [2]. Further exploration of the GfE cosmology reveals further aspects of the GfE thermodynamics reconciling the second principle of thermodynamics with the decrease of the QGRE and thus possibly with the emergence of non-uniform local structures [3]. A canonical quantization of this field theory could bring new insights into quantum gravity and the outstanding problem of its renormalization. [1] Bianconi, G., 2025. Gravity from entropy. Physical Review D, 111(6), p.066001. [2] Bianconi, G., 2025. The quantum relative entropy of the Schwarzschild black hole and the area law. Entropy, 27(3), p.266. [3] Bianconi, G., 2026. Thermodynamics of the gravity from entropy theory. Physical Review D, 114(2), p.024042.
11:30 Asymptotically safe quantum gravity: functional and lattice perspectives - Marc Schiffer (Radboud University)
Asymptotically safe quantum gravity: functional and lattice perspectives
- Marc Schiffer (Radboud University)
11:30 - 12:00
Room: Large Lecture Theatre Asymptotically safe quantum gravity might provide a UV complete description of nature, governed by scale-invariance realized at an interacting RG fixed point. In this talk, I will introduce Dynamical Triangulations as a tool complementary to functional methods, to explore this scenario. I will give an overview on the status of asymptotic safety from lattice studies, and focus on recent studies of matter correlators on these fluctuating lattices. On the one hand, these correlators serve as a probe of the underlying geometry and provide crucial insights into the quantum nature of geometry. On the other hand, they also allow to extract physical information, e.g., the mass anomalous dimension, and hence serve as an important bridge to functional studies. There, such critical exponents have been recently studied to high precision by resumming higher-order operators. Hence, recent progress in the study of matter correlators with functional and lattice methods pave the way towards quantitative comparison of both methods, and hence to robust, method independent insights into the quantum nature of spacetime.
12:00 Buffet Lunch
Buffet Lunch
12:00 - 14:00
Room: Atrium
14:00 Parallel Session: Room 1
Room 1
14:00 - 15:40
Room: Large Lecture Theatre
Contributions

14:00 $d \geq 4$ gravitational vacua and black hole thermodynamics from $2D$ dilaton theories - Johanna Borissova (Imperial College London)

14:20 Entanglement and renormalization-group flow - Nikolaos Tetradis (National and Kapodistrian University of Athens (GR))

14:40 How Sensitive is Cosmic Inflation to Quantum Corrections? An ERG Approach. - Lucien Heurtier (King's College London)

15:00 The axion coupling accelerates the Universe through \cPT-symmetric phases - Sarben Sarkar (King's College London)

15:20 Prospects for scalar-tensor cosmology in asymptotically safe quantum gravity - Fabian Wagner (Heidelberg University)
Parallel Session: Room 2
Room 2
14:00 - 15:40
Room: 155
Contributions

14:00 Thermal precondensation and its appeareance in gauge-fermion theories - Alvaro Pastor Gutierrez (RIKEN iTHEMS)

14:20 Functional Renormalization Group Flows and Gauge Consistency - Katsumi Itoh (Niigata University)

14:40 The Fate of Chiral Gauge Theory - Hao-Lin Li (Sun Yat-Sen University)

15:00 Diquark Properties from First Principles - Ugo Mire

15:20 Functional Renormalization of QCD in 1+1 dimensions - Eric Oevermann (Friedrich Schiller University Jena)
Parallel Session: Room 3
Room 3
14:00 - 15:40
Room: 144
Contributions

14:00 Informational renormalization group - Takato Mori (Rikkyo University)

14:20 Exploring multi parameter optimization in FRG - Gian Paolo Vacca (INFN - Bologna section)

14:40 Non-Gaussian statistics of the order parameter across a continuous phase transition - Adam Rançon (Université de Lille)

15:00 Universal Crossover in the Three-Channel Charge Kondo Model at High Transparency - Nicolas Paris (LPTMC Sorbonne Université)

15:20 The Adjoint Field as an Influence Map: Sensitivity Analysis of FRG Flows - Ashutosh Dash
15:40 Coffee
Coffee
15:40 - 16:10
Room: Atrium
16:10 Stochastic observables and constructive RG - Massimiliano Gubinelli (University of Oxford)
Stochastic observables and constructive RG
- Massimiliano Gubinelli (University of Oxford)
16:10 - 16:40
Room: Large Lecture Theatre Scale-dependent observables are the basic concept of the renormalization group. I will present a recent formalisation of this idea in the context of the probabilistic approach to Euclidean QFT and how it gives naturally rise to various structures, in particular local diffusions called Wilson-Ito diffusions which generalise the ideas of Polchinski’s RG and also RG for stochastic equations.
16:40 Diffusion Models as Stochastic Quantisation - Lingxiao Wang (RIKEN)
Diffusion Models as Stochastic Quantisation
- Lingxiao Wang (RIKEN)
16:40 - 17:10
Room: Large Lecture Theatre Generative diffusion models — the engine behind much of modern image and video synthesis — turn out to admit a transparent physical reading: the forward process is a Langevin diffusion that washes out structure, while the reverse, score‑driven process reconstructs configurations from noise, realising a stochastic quantisation à la Parisi–Wu with the learned score playing the role of the drift derived from an effective action. Building on this correspondence, I will present our recent results from the DM‑QFT collaboration on generative sampling for lattice field theory: scalar theories in two and three dimensions including their critical regions, group‑preserving diffusion for U(N)/SU(N) gauge fields, and ongoing progress. I will emphasise Expandability, Exactness and Efficiency, and close with the road ahead QCD.
17:10 Renormalisation Group approach to General Relativity - Kevin Falls
Renormalisation Group approach to General Relativity
- Kevin Falls
17:10 - 17:40
Room: Large Lecture Theatre In this talk I will discuss a new approach to classical general relativity. Currently, most analytical methods to general relativity are inherently perturbative, while Numerical Relativity remains computationally expensive. I will present a middle path: an exact renormalization group (RG) equation for classical gravitational systems. The equation correctly reproduces the Post-Minkowskian expansion, while also easily recovers the 1PN two-body action, bypassing the need for complex three-graviton vertex calculations. I will then show how the equation can be derived from the classical limit of the Polchinski equation, demonstrating its exactness. This establishes the exact RG as a powerful new tool for tackling strong-field dynamics in gravity.
Thursday, 3 September 2026
09:00 Parallel Session: Room 1
Room 1
09:00 - 10:20
Room: Terrace Room
Contributions

09:00 Asymptotically safe Standard Model - Astrid Eichhorn

09:20 Fixed points of the renormalisation group flow the CKM and PMNS matrices : CP violation in the Standard Model and beyond - Brian Dolan (Dublin Institute for Advanced Studies)

09:40 Near-criticality of the neutrino sector of the Standard Model - Zois Gyftopoulos (Heidelberg University)

10:00 Quantum gravity contributions to the gauge and Yukawa couplings in proper time flow - Daniele Rizzo (KBFI-Tallinn)
Parallel Session: Room 2
Room 2
09:00 - 10:20
Room: Gallery Room 1
Contributions

09:00 Rethinking Dimensional Regularization in Critical Phenomena - Alessandro Codello (Ca' Foscari)

09:20 Functional Dimensional Regularization for O(N) Models - Piero Beretta (Facultad de Ingeniería. Universidad de la República)

09:40 Perturbatively Exact Fixed Points in Three Dimensions - Tom Steudtner

10:00 Mass generation at a fixed point: A Functional Renormalization Group Study of the tricritical O(N) model in d=3 and N=∞ - Shunsuke Yabunaka (ASRC, JAEA)
Parallel Session: Room 3
Room 3
09:00 - 10:20
Room: Gallery Room 2
Contributions

09:00 Density functional theory of renormalization group in nuclear matter - Wei-jie Fu (Dalian University of Technology)

09:20 Precondensation and inhomogeneous instabilities in high-density QCD - Franz Richard Sattler (University Bielefeld)

09:40 Pion Distribution Amplitudes from Functional QCD - Chuang Huang (Heidelberg University, ITP)

10:00 FRG Constraints on Diquark Pairing: Implications for Color-Superconducting Quark Matter - Bernd-Jochen Schaefer
10:20 Coffee
Coffee
10:20 - 11:00
Room: Conference Centre
11:00 Parallel Session: Room 1
Room 1
11:00 - 12:20
Room: Terrace Room
Contributions

11:00 Spectral Functions of Lorentzian Quantum Gravity - Gabriel Assant

11:20 Unitarity at all scales: Towards 2-to-2 scattering of scalars in Asymptotically Safe Quantum Gravity. - Angelo Portas Chiesa (University of Sussex)

11:40 Understanding IR divergences in higher derivative theories - Diego Buccio (Heidelberg University)

12:00 Renormalization Group Approach to the Gravitational Two-Body Problem - Facundo Gutierrez (Universidad de la Republica, Uruguay)
Parallel Session: Room 2
Room 2
11:00 - 12:20
Room: Gallery Room 1
Contributions

11:00 A complex LPA for the critical and multicritical Lee-Yang fixed points - Fanny Eustachon (École polytechnique)

11:20 Exploring Temperature-Resistant Order in Quantum Field Theories - Bilal Hawashin

11:40 Derivative Expansion, Frustrated Antiferromagnets and $O(N)\times O(2)$ models - Nicolás Wschebor (Instituto de Física de la Facultad de Ingeniería, Udelar (Uruguay))

12:00 Critical Phenomena on the Bethe Lattice - Saswato Sen (Okinawa Institute of Science and Technology)
Parallel Session: Room 3
Room 3
11:00 - 12:20
Room: Gallery Room 2
Contributions

11:00 Triviality doesn't mean Gaussianity: A Renormalization Group perspective - Sankarshan Sahu (LPTMC, Sorbonne Université)

11:20 SO (1, d+1) symmetry of the exact RG equation - Semanti Dutta (S.N. Bose National Center for Basic Sciences)

11:40 Summation of logarithmic quantum corrections based on the locality of QFT - Alfiia Mukhaeva (Joint Institute for Nuclear Research)

12:00 Linearity in the renormalization group equations - Denis Tolkachev (Joint Institute for Nuclear Research)
12:20 Buffet Lunch
Buffet Lunch
12:20 - 13:30
Room: Conference Centre

13:30 Confernce Excursion
Confernce Excursion
13:30 - 17:30
Friday, 4 September 2026
09:00 Zonostrophic instability in beta-plane turbulence - Léonie Canet (Université Grenoble Alpes)
Zonostrophic instability in beta-plane turbulence
- Léonie Canet (Université Grenoble Alpes)
09:00 - 09:30
Room: Large Lecture Theatre We study a simplified model of geophysical flows, called beta-plane turbulence, which is built on the two-dimensional Navier-Stokes equation in the presence of differential rotation, ie a northward gradient of the local vertical rotation rate (beta-effect). When strong enough, the beta-effect triggers a zonostrophic instability, leading to the spontaneous emergence of zonal jets, which are large, banded, anisotropic alternating jets in the zonal direction. The complete theoretical description of the statistical properties of the jets and the related scaling regimes is still lacking. In this work, we use FRG to study the conditions for the zonostrophic instability, and we calculate the energy spectra associated with the jets and the background fluid.
09:30 Weak to strong wave turbulence: RG, large N, and epsilon expansion - Vladimir Rosenhaus
Weak to strong wave turbulence: RG, large N, and epsilon expansion
- Vladimir Rosenhaus
09:30 - 10:00
Room: Large Lecture Theatre The theory of wave turbulence -- developed over the past five decades -- is a consistent framework for describing cascades in a broad class of weakly interacting systems including: waves in the ocean, plasma waves, spin waves, acoustic waves, and many others. The Kolmogorov-Zakharov scaling for the distribution of mode occupation numbers is a solution of the weakly interacting kinetic equations, which been verified numerically and/or experimentally in a number of contexts. If the flux pumped into the system is large, or even if the flux is small and one is far along the cascade (at a wavenumber that differs significantly from the pumping scale) -- as is often the case in physical realizations -- the standard weak wave turbulence theory is insufficient. We describe how this problem of find strong wave turbulence scaling can be mapped onto a problem of renormalization group flows in far-from-equilibrium states. Two contexts are solvable. The first is large N: We study turbulent cascade in a large N nonlinear Schrodinger equation. We find two forms of universality in the strong turbulence spectrum: in focusing media it is independent of the flux magnitude (the widely used critical balance solution), while in defocusing media it is independent of the bare coupling constant, with the largest scale appearing instead. These results are confirmed by direct numerical simulation. The second is the epsilon expansion. We conclude with a discussion of how FRG may be a useful tool for solving the problem of strong wave turbulence scaling in a general nonlinear system.
10:00 Universality Far from Equilibrium: New Fixed Points and New Challenges for RG - Chiu Fan Lee (Imperial College London)
Universality Far from Equilibrium: New Fixed Points and New Challenges for RG
- Chiu Fan Lee (Imperial College London)
10:00 - 10:30
Room: Large Lecture Theatre The renormalization group starts from an effective field theory -- but where does that theory come from? In hydrodynamics, the relevant degrees of freedom and symmetries can themselves emerge at long wavelengths. The Navier–Stokes equation provides a paradigmatic example: conservation laws and emergent symmetries strongly constrain the form of the long-wavelength theory, largely independently of microscopic details. Far from equilibrium, this hydrodynamic viewpoint becomes particularly fertile. Unshackled by detailed balance, the space of allowed dynamical theories expands dramatically: new nonlinearities become possible, emergent symmetries can arise, and RG fixed points and universality classes (UCs) proliferate [1]. I will illustrate these ideas using active matter. I will first discuss the ordered phase of polar flocks [2–6], where emergent symmetries strongly constrain the RG flow and can lead to exact scaling relations. I will then turn to the critical behaviour of active Ising models, where nonequilibrium couplings generate a remarkably rich fixed-point structure, including a new UC that supersedes the equilibrium Wilson–Fisher UC as the generic description of the critical transition [7]. These examples highlight two complementary challenges for RG far from equilibrium: constructing the appropriate long-wavelength theory and tackling the proliferation of nonlinearities that arises once the constraints of equilibrium are lifted. I will conclude by asking whether functional RG approaches can help address the latter challenge. [1] P. Jentsch and C. F. Lee, Hydrodynamics, Renormalization Group, and Universality Classes Far from Equilibrium, arXiv:2607.02318. [2] L. Chen, C. F. Lee, and J. Toner, Mapping two-dimensional polar active fluids to two-dimensional soap and one-dimensional sandblasting, Nat. Commun. 7, 12215 (2016). [3] L. Chen, C. F. Lee, and J. Toner, Incompressible polar active fluids in the moving phase in dimensions d > 2, New J. Phys. 20, 113035 (2018). [4] L. Chen, C. F. Lee, and J. Toner, Moving, Reproducing, and Dying Beyond Flatland: Malthusian Flocks in Dimensions d > 2, Phys. Rev. Lett. 125, 098003 (2020). [5] L. Chen, C. F. Lee, A. Maitra, and J. Toner, Dynamics of packed swarms: Time-displaced correlators of two-dimensional incompressible flocks, Phys. Rev. E 109, L012601 (2024). [6] P. Jentsch and C. F. Lee, New Universality Class Describes Vicsek’s Flocking Phase in Physical Dimensions, Phys. Rev. Lett. 133, 128301 (2024). [7] M. Wong and C. F. Lee, New Universality Classes Govern the Critical and Multicritical Behavior of an Active Ising Model, arXiv:2507.06068.
10:30 Coffee
Coffee
10:30 - 11:00
Room: Atrium
11:00 Exact RG and generative diffusion model - Yuto Ashida (The University of Tokyo)
Exact RG and generative diffusion model
- Yuto Ashida (The University of Tokyo)
11:00 - 11:30
Room: Large Lecture Theatre In recent years, the rapid advancement of generative AI, particularly diffusion models, has led to the adoption of new data-driven methods in widely diverse fields—from high-quality image generation to drug discovery and material design. In this talk, I will discuss their theoretical similarities to the theory of the exact renormalization group widely used in statistical and high-energy physics. Specifically, I will introduce an approach based on RG concepts that aim to capture the hierarchical structure of data more efficiently. Based on K. Masuki and YA, arXiv:2501.09064
11:30 The Hunting of Physics with Machine Learning through the (f)RG Looking Glass, and what we found there: An Agony, in two to eight Fits - Jan M. Pawlowski
The Hunting of Physics with Machine Learning through the (f)RG Looking Glass, and what we found there: An Agony, in two to eight Fits
- Jan M. Pawlowski
11:30 - 12:00
Room: Large Lecture Theatre In this talk I give a -certainly incomplete- overview of the rapidly growing area of (i) physics and renormalisation group applications with Machine Learning as well as (ii) Machine Learning with the renormalisation group. Applications (i) use the nonlinear optimisation property of neural networks for physics. Applications (ii) use the fact that the layerwise or even global information transport in deep neural architectures is either explicitly or implicitly a general (functional) renormalisation group transformation. Specifically, this allows us to endow generative architectures which much-needed information beyond the learning sample. Applications and ideas in (i,ii) are illustrated within simple examples.
12:00 Non-Fermi-liquid metals and phase reconstruction: an FRG perspective - Chris Hooley (Coventry University)
Non-Fermi-liquid metals and phase reconstruction: an FRG perspective
- Chris Hooley (Coventry University)
12:00 - 12:30
Room: Large Lecture Theatre In this talk, I will briefly review the projects from my group’s work over the past decade or so in which the functional renormalisation group (FRG) has played a significant role. Most of these concern the theoretical description of non-Fermi-liquid metals (strongly interacting fermionic fluids without Landau quasiparticles), which often occur due to proximity to a quantum critical point. I shall present results on non-Fermi-liquids caused by proximity to a ferromagnetically ordered phase [1], proximity to a Pomeranchuk instability [2], and the presence of a gauge boson [3]. I shall also briefly present some recent results in which the numerical truncated-unity functional renormalisation group (TU-FRG) method is used to predict the phase reconstruction that occurs in the vicinity of a higher-order Van Hove point in the non-interacting band structure of the material [4]. [1] S. P. Ridgway and CAH, “Non-Fermi-Liquid Behavior and Anomalous Suppression of Landau Damping in Layered Metals Close to Ferromagnetism,” Phys. Rev. Lett. 114, 226404 (2015). [2] M. J. Trott and CAH, “Non-Fermi-liquid fixed points and anomalous Landau damping in a quantum critical metal,” Phys. Rev. B 98, 201113(R) (2018). [3] T. P. Sheerin and CAH, “Non-Fermi liquid induced by U(1) gauge-field interactions: A functional renormalization group analysis,” Phys. Rev. Research 7, 023216 (2025). [4] T. P. Sheerin, M. Ramirez, CAH, and L. C. Rhodes, “Engineering correlated phases through manipulation of Van Hove singularities,” arXiv preprint 2608.07714 (2026).
12:30 Lunch
Lunch
12:30 - 14:00
14:00 Parallel Session: Room 1
Room 1
14:00 - 15:40
Room: Large Lecture Theatre
Contributions

14:00 Scaling regimes of the 1D Kuramoto-Sivashinsky equation - Liubov Gosteva (UGA)

14:20 Long range to short range crossover in one dimension - Tilman Enss (Heidelberg University)

14:40 Dynamical criticality beyond the overdamped limit - Laura Batini

15:00 Wave interaction in astrophysical plasmas - Olivier Coquand (LAMPS/University of Perpignan)

15:20 A Functional Renormalization Group Approach to Anomaly Detection via Dimensional Phase Transitions - Riccardo Finotello (CEA Paris-Saclay)
Parallel Session: Room 2
Room 2
14:00 - 15:40
Room: 155
Contributions

14:00 Physics-informed neural networks for solving FRG - Takeru Yokota

14:20 Solving Functional Renormalization Group Equations with Neural Networks - Yang-yang Tan

14:40 Existence theorem on the UV limit of Wilsonian RG flows - Andras Laszlo (HUN-REN Wigner Research Centre for Physics (HU))

15:00 Flow equations of second order - Stefan Floerchinger (University of Jena)

15:20 Singularities in the RG flow - Antal Jakovác (Wigner Research Centre for Physics)
Parallel Session: Room 3
Room 3
14:00 - 15:40
Room: 144
Contributions

14:00 Fermionic fRG with interaction flows : applications to electron-phonon systems - Kilian Fraboulet

14:20 Renormalisation group approaches for SU(N)xSU(M) symmetric Hubbard models - Hannes Braun (Technische Universität München, Max Planck Institute for Solid State Research)

14:40 Functional renormalization group approach to boson-induced superconductivity in Bose-Fermi mixtures - Richard Schmidt (Institute for Theoretical Physics, Heidelberg University, Germany)

15:00 Functional renormalization group for extremely correlated electrons - Andreas Rückriegel (Frankfurt University)

15:20 Control of ordered phases by manipulation of Van Hove singularities: insights from truncated-unity FRG - Thomas Sheerin (University of St Andrews)
15:40 Coffee
Coffee
15:40 - 16:10
Room: Atrium
16:10 Defect conformal field theories that are free in the bulk: A status report - Christopher Herzog
Defect conformal field theories that are free in the bulk: A status report
- Christopher Herzog
16:10 - 16:40
Room: Large Lecture Theatre Conformal field theories are relativistic quantum field theories with conformal symmetry. Defect CFTs have point or line or planar defects that further reduce the conformal symmetry to that of the defect. When the bulk is free and massless — a free massless scalar or fermion or photon — there are strong constraints on the conformal data that raise hope of achieving a partial or total classification of these theories. Moreover, some may have relevance for graphene, carbon nanotubes, and other experimental systems. We will survey recent results about these systems, including work in progress on free in the bulk fermions.
16:40 TBC - Enrico Pajer (University of Cambridge)
TBC
- Enrico Pajer (University of Cambridge)
16:40 - 17:10
Room: Large Lecture Theatre
19:00 Conference Dinner
Conference Dinner
19:00 - 22:00
Room: Hotel Malmaison
Saturday, 5 September 2026
09:30 Fermi scale from quantum gravity scaling solution - Christof Wetterich
Fermi scale from quantum gravity scaling solution
- Christof Wetterich
09:30 - 10:00
Room: Large Lecture Theatre We propose that quantum gravity may predict the Fermi scale. Fundamental scale invariance implies the scale invariant standard model. Both the Fermi scale and the Planck mass are given by fields, and their ratio is dictated by a dimensionless cosmon-Higgs coupling. For an ultraviolet fixed point of quantum gravity this coupling is an irrelevant parameter of the renormalization flow and becomes predictable. An analytic scaling solution for quantum gravity admits no free parameter for the mass term of the Higgs boson. We discuss a new asymptotically safe quantum gravity fixed point for which the scalar potential is not flat.If the largest intrinsic mass scale generated by the renormalisation flow away from this fixed point is sufficiently below the Fermi scale, the couplings of the scale invariant standard model are determined by the scaling solution. For a given short distance model remaining valid to infinitely small distances the ratio Fermi scale over Planck mass can then be predicted. With reasonable assumptions for the ultraviolet fixed point a numerical solution finds a tiny value for the ratio between the Fermi and Planck scales, very close to a second order quantum electroweak phase transition. This could explain the observed gauge hierarchy.
10:00 TBC - Neil Turok (University of Edinburgh)
TBC
- Neil Turok (University of Edinburgh)
10:00 - 10:30
Room: Large Lecture Theatre
10:30 Coffee
Coffee
10:30 - 11:00
Room: Atrium
11:00 Asymptotic behaviour of the derivative expansion in the ERG - Tim Morris (University of Southampton)
Asymptotic behaviour of the derivative expansion in the ERG
- Tim Morris (University of Southampton)
11:00 - 11:30
Room: Large Lecture Theatre We show that the derivative expansion of the exact (functional) renormalization group is a divergent series in any dimension, both for an exponential cutoff and more general smooth cutoffs. We prove this by showing that within massless $\lambda\varphi^4$ perturbation theory, such divergences arise first at two loops. From several lines of theoretical argument and by analysing infinite classes of two- and three-loop contributions, we conclude that the derivative expansion is an asymptotic series that initially converges towards the exact result before divergent behaviour takes over.
11:30 Applications of the physics-informed renormalisation group - Friederike Ihssen (ITP Heidelberg)
Applications of the physics-informed renormalisation group
- Friederike Ihssen (ITP Heidelberg)
11:30 - 12:00
Room: Large Lecture Theatre The resolution of strongly correlated systems is a computationally challenging task, which can be simplified enormously by choosing a formulation in terms of the appropriate degrees of freedom. Here, we distinguish between transformations of the fundamental degrees of freedom in the path integral, and transformations of mean fields. Both are incorporated naturally in the renormalisation group approach and appear as dynamic, infinitesimal changes of the field representation with changing scales. A historically very prominent use case is dynamic rebosonisation, which implements the Hubbard-Stratonovich transformation throughout the RG flow, but recent investigations are studying a wider field of applications. In my talk I will discuss the point of view of the physics-informed RG (PIRG) [1,2], which considers both the flow of a generating functional and the flow of the field on equal footing. This pair must fulfill a generalised flow equation and an additional constraint equation that can be chosen to suit a specific purpose. Firstly, I we consider the PIRG for microscopic field-transformations [3]. Here, they bridge the gap to generative sampling architectures in lattice field theory. Specifically, the optimal transport nature of the RG allows to address long standing problems such as the sign-problem in real-time lattice simulations [4]. Secondly, I consider generalised flows of the effective action. Here the PIRG perspective allows to formulate novel optimisation procedures for expansion schemes [5,6], or the restoration of gauge symmetries which are explicitly broken by the RG flow [7,8]. [1] FI, J. M. Pawlowski, Annals Phys. 481 (2025) 170177 [2] FI, J. M. Pawlowski, Phys.Rev.D 113 (2026) 7, 076003 [3] FI, R. Kapust, J. M. Pawlowski, arXiv:2510.26678 [4] FI, R. Kapust, J. M. Pawlowski, arXiv:2603.03159 [5] FI, J. M. Pawlowski, arXiv:2305.00816 [6] A. Bonanno, FI, J. M. Pawlowski, SciPost Phys.Core 9 (2026) 005 [7] FI, J. M. Pawlowski, Phys.Rev.D 112 (2025) 10, 105005 [8] FI, B. Knorr, S. Mezger, J. M. Pawlowski, P. Sprenger, In preparation
12:00 Functional Renormalization and relativistic Luttinger fermions - Holger Gies (FSU Jena)
Functional Renormalization and relativistic Luttinger fermions
- Holger Gies (FSU Jena)
12:00 - 12:30
Room: Large Lecture Theatre We study the renormalization flow of relativistic Luttinger fermions as a new ingredient for the construction of UV-complete quantum field theories. The resulting fermion fields exhibit a canonical scaling different from Dirac fermions and thus support the construction of novel relativistic and perturbatively renormalizable, interacting quantum field theories in four spacetime dimensions. In particular, new asymptotically free self-interacting field theories can be identified, representing first examples of high-energy complete quantum field theories based on purely fermionic matter degrees of freedom. As examples, we discuss models which undergo dimensional transmutation and low-energy condensate formation with scalar excitations on top of the condensate. A corresponding Yukawa model exhibits features similar to self-organized criticality with a natural separation of low-energy observables from high energy initial scales without the need for any fine-tuning. We also critically examine the analytic structure of the Luttinger-fermionic propagator in the various gapped phases and discuss possible consequences for asymptotic states.
12:30 Lunch
Lunch
12:30 - 13:30