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01/09/2026, 09:00
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Prof. Igor Herbut (Simon Fraser University)01/09/2026, 09:30Invited Plenary
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...
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Dr Lennart Klebl (University of Würzburg)01/09/2026, 10:00Invited Plenary
In this talk, I introduce the first open-source functional
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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.... -
Prof. Nicolo Defenu01/09/2026, 11:00Invited Plenary
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...
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Laura Classen (Max-Planck-Institut for Solid State Research)01/09/2026, 11:30Invited Plenary
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...
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Paweł Jakubczyk (Institute of Theoretical Physics, Faculty of Physics, University of Warsaw)01/09/2026, 13:40Talk
We readdress quantum criticality of itinerant Fermi systems in dimensionality d=2 adopting the Wetterich equation as the starting point. Upon neglecting Fermi self-energy in the loop integrals of the functional RG flow, we identify a non-Fermi liquid RG fixed point and recover the features of earlier RPA-type approaches in the entire frequency range. In a subsequent step, focusing on the...
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Charlie Cresswell-Hogg01/09/2026, 13:40
Four-fermion interactions are important in many areas of particle physics, from effective descriptions of weak interactions and QCD to parametrisations of new physics in SMEFT or HEFT. In this talk I demonstrate that four-fermion interactions may develop strongly coupled UV fixed points in four dimensional QFTs. Contrary to weakly coupled expectations, their high energy limit may be (near-)...
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Yuepeng Guan (Jilin University)01/09/2026, 13:40Talk
We study topological properties of a quantum mechanical system with $U(1)$-symmetry within the functional renormalisation group (fRG) approach. These properties include the vacuum energy structure and the topological susceptibility. Our approach works with a complexification of the flow equation, and specifically we embed the original symmetry into the complex plane, $U(1)\rightarrow...
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Francesco Del Porro (Niels Bohr Institute)01/09/2026, 14:00Talk
The existence of an ultraviolet (UV) fixed point in the renormalization group (RG) flow of gravity provides a non-perturbative route to renormalizing gravity, that is Asymptotically Safe Quantum Gravity. Evidence for such a UV completion has been found in a variety of settings, including higher-derivative gravity theories and gravity–matter systems. However, despite its apparent robustness, it...
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Tom Steudtner01/09/2026, 14:00Talk
I will report about recent progress to systematise the search for non-trivial fixed points in three dimensions. I revisit the stability of the UV fixed point in purely scalar theories using perturbation theory. I will discuss how the results are compatible with FRG, and address an old controversy in the literature. Furthermore, scalar-fermionic theories are investigated up to four-loop order,...
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Mireia Tolosa-Simeón01/09/2026, 14:00Talk
Interaction-induced quantum phase transitions in Dirac materials, known as relativistic Mott transitions, involve spontaneous symmetry breaking and are accompanied by a non-vanishing expectation value of a scalar order parameter. For the first time, such transitions have recently been observed experimentally in moiré Dirac materials through the tuning of the twist angle. In this contribution,...
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Vincent Grison (Sorbonne Université)01/09/2026, 14:20Talk
One-dimensional interacting bosons subjected to disorder are known to possess an insulating ground state, called the Bose glass. At finite temperature, perturbative computations advocate for a crossover to a non-disordered normal fluid, but an alternative scenario was also suggested, arguing for the existence of a genuine phase transition. The resulting low-temperature insulating phase is then...
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Max Uetrecht (TU Dortmund University)01/09/2026, 14:20Talk
Recently, the familiar $S$ matrix form $S=1+iT$ and crossing rules were challenged in Chern--Simons theories coupled to bosonic or fermionic matter. In the planar large-$N$ singlet channel, the proposed modifications restore unitarity by changing both the forward identity contribution and the crossing relation obeyed by the $T$ matrix. In this talk, we present a direct perturbative calculation...
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Anca Preda (Lund University)01/09/2026, 14:20Talk
The idea of supplementing the number of spacetime dimensions has long been deemed as one of the potential extension of the Standard Model, as it provides powerful tools to explain some of its shortcomings. One example of higher-dimensional formulations are asymptotic grand unified theories (aGUTs), for which the couplings do not meet at a high scale, but instead flow together towards a fixed...
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Ivan Balog (Institute of Physics, Zagreb)01/09/2026, 14:40Talk
We study disorder-dominated quantum models, including Ising-like random-field systems and equilibrium pinned elastic-manifold problems, near their zero-temperature critical regimes. We provide an explicit field-theoretic calculation supporting the fluctuationless fixed point scenario, in which the infrared critical fixed point is classical and quantum fluctuations enter through a dangerously...
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Félix Rose (LPTM, CY Cergy Paris Université)01/09/2026, 14:40
In a quantum field theory, the product of two operators in the short distance limit can be expressed as a sum of operators multiplied by functions (when inserted in any correlation function).
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This so-called operator product expansion (OPE) is of fundamental importance in the study of conformal field theories (CFTs) in two and higher dimensions. There, due to the the conformal symmetry, the... -
Andreas Trautner (CFTP, IST, University of Lisbon)01/09/2026, 14:40Talk
I will show how the existence of an outer automorphism (Out) provides a sufficient condition for the existence of an RG fixed hyperplane (fixed point, separatrix) in the renormalization group (RG) flow of a Quantum Field Theory (QFT). This gives a systematic way to derive non-perturbative all-order constraints on the RG beta functions and provides the mathematical underpinning of 't Hooft's...
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Mr David Dullaway (University of Sussex)01/09/2026, 15:30Poster
Over the past few decades, significant evidence for an asymptotically safe fixed point in quantum gravity has accumulated. An important direction of research relates to the inclusion of higher-curvature interactions. Stable results have been found in "vertical" extensions involving increasing powers of Ricci scalars and tensors, Riemann tensors, and specific combinations thereof, up to order...
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Stijn Hennissen (Radboud University)01/09/2026, 15:31Poster
We provide a novel computational method for constructing the UV-critical surface along the lines of [arXiv:2403.08541]. Using physics informed neural networks to learn flow invariants, we recover the UV-critical surface all at once. The method is successfully applied to a UV-critical surface for an asymptotically safe scalar-tensor theory, where we predict the IR effective field theory. We...
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Edwyn Tecedor (LPTHE - Sorbonne Université)01/09/2026, 15:32Poster
Resurgence in Ward–Schwinger–Dyson Equations for QED
Edwyn Tecedor (1)(3), Marc Bellon (1)(2), Redamy Perez-Ramos (1)(3)
(1) Sorbonne Université LPTHE , CNRS (2), IPSA (3), Paris, FrancePerturbative expansions in quantum field theory are divergent, with coefficients exhibiting factorial growth. Resurgence analysis provides a systematic framework to decode this growth and extract...
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Dominik Chudy (RWTH Aachen University), Jan Herre (RWTH Aachen University)01/09/2026, 15:33Poster
We introduce a functional renormalization group framework formulated directly in the Floquet steady-state that systematically incorporates frequency-dependent interaction effects. By retaining the frequency structure of the two-particle vertex up to second order in interaction strength, our approach provides controlled access to dynamical response functions and nonequilibrium transport in...
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Fabrizio Chicconi (University of Pisa, INFN), Dr Luca Parente (University of Pisa, INFN)01/09/2026, 15:34
Scale-invariant extensions of gravity, particularly quadratic gravity, offer a compelling setting due to their perturbative renormalizability and potential asymptotic freedom. Formulated in Weyl geometry, these models naturally allow physical energy scales, such as the Planck mass, to emerge dynamically through a spontaneous symmetry‑breaking mechanism, which in turn enables the recovery of an...
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Juan Fernandez Molinero (Radboud University)01/09/2026, 15:35Poster
Coupling gravity to the U(1) gauge sector induces higher-order gauge interactions that can be investigated using functional renormalization group (FRG) techniques. Within the framework of Asymptotic Safety, previous studies have shown that the existence of ultraviolet (UV) completions for these induced interactions can impose constraints, for example, on the strength of gravitational...
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Iason Vakondios01/09/2026, 15:36Poster
We investigate multicritical points in O(N) symmetric scalar field theories in various dimensions. Using functional renormalisation to leading order in a derivative expansion, we find analytical and numerical results for critical and multi-critical points. In the large-N limit, we investigate local and global fixed points, and the availability of lines of fixed points analogous to the BMB...
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Vatsalya Vaibhav (University of Edinburgh)01/09/2026, 15:37Poster
It turns out that imposing reflecting boundary conditions at the Big Bang singularity itself is sufficient to explain the CMB Power spectrum without the assumption of an exotic epoch preceding radiation era. However, there are well known problems with starting the Universe in a radiation dominated phase such as the horizon problem, overproduction of dark matter, and thermalization of...
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Mr Gabriel Weigert (Friedrich-Schiller-Universität Jena)01/09/2026, 15:38Poster
In this work, we investigate aspects of resurgence in quantum electrodynamics (QED) in strong external background fields. Resurgence provides a framework for understanding how divergent perturbative series can be related to non-perturbative contributions. In particular, we study the vacuum polarization tensor and the mass operator, or electron self-energy, in a self-dual background field in...
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Moritz Gessner (Universität Heidelberg)01/09/2026, 15:39Poster
Quantum gravity impacts Standard Model particles through effective interactions generated by renormalization. These appear as SMEFT operators, which correct Standard Model dynamics at energies between the electroweak symmetry breaking scale and the Planck scale. As a step to predicting SMEFT coefficients from asymptotic safety, we investigate the flow of a representative collection of...
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Jorge Ibañez (Universidad de la República (UdelaR))01/09/2026, 15:40Poster
In the critical regime of statistical-mechanical systems, thermodynamic quantities follow power laws as functions of a control parameter due to the effective interaction of the system at all scales. This universal behavior is associated with scale invariance and, in many cases, extends to conformal invariance, that is, invariance under the most general group of transformations that preserve...
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Ana García-Page (Max-Planck-Institut for Solid State Research)01/09/2026, 15:41Poster
Chiral quantum phase transitions in Dirac materials at finite density: Strong enough interactions induce a semimetal-to-insulator transition in Dirac materials, which can be viewed as the solid-state analogue of the chiral phase transition in quantum chromodynamics. Moiré Dirac materials such as twisted bilayer graphene offer a new opportunity to study this transition because they facilitate...
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Nahzaan Riyaz (University of Sussex)01/09/2026, 15:42Poster
Interacting fixed points of the renormalisation group play a central role in determining whether or not quantum field theories exhibit conformal behaviour. In this work, we investigate the conformal windows of weakly coupled fixed points in gauge-matter theories, through a systematic loop-by-loop analysis of perturbative beta functions in the large $N$ Veneziano limit. Our focus is on two...
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Carter Goldman (University of Sussex)01/09/2026, 15:43Poster
Supporters of the Bayesian Brain Hypothesis argue that the brain maintains a generative model of the environment and inverts this model to infer the states of the world. Message-passing is one class of algorithms that performs this computation tractably. While there is some evidence that the brain uses specific forms of message-passing, such as mean-field variational inference, other...
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Paul Philip Sprenger (Institute for Theoretical Physics, Heidelberg University)01/09/2026, 15:44Poster
In Quantum Gravity, the regulator breaks diffeomorphism symmetry and background independence. In this talk, we reinstate gauge invariance and background independence by a field redefinition at every renormalisation group step and discuss the properties of the resulting Reuter fixed point. Moreover, we show improved stability results for simple gravity-matter systems.
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Yaniss Rabahi (PhLam laboratory)01/09/2026, 15:45Poster
We investigate the thermodynamics of the two-dimensional Bose gas within the framework of the non-perturbative functional renormalization group (NP-FRG) and quantum phase transitions. The existence of a quantum critical point in the vacuum-superfluid transition implies that thermodynamic functions can be expressed as universal scaling functions [1]. Furthermore, using the flow equations of the...
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Lidia Marino (ITP-Heidelberg)01/09/2026, 15:46Poster
Black-hole uniqueness is expected to break in theories beyond General Relativity. This breaking can take a particularly strong form, if several branches of black-hole solutions beyond the Kerr solution coexist. We find an example of a theory that exhibits such strong breaking, where, at fixed couplings, two different scalarization mechanisms types coexist for spinning black holes. We test such...
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Rowan Packer (University of Sussex)01/09/2026, 15:47Poster
We study the interplay of scalar matter with quantum gravity in the Lorentzian signature using the recently developed spectral fRG. The spectral fRG is based on the Callan-Symanzik cutoff, which acts as a scale-dependent mass and preserves the Källén-Lehmann spectral representation, in combination with dimensional regularisation. In this setup, we compute the impact of N_S minimally coupled...
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Benjamin Knorr (Heidelberg University)01/09/2026, 16:00Invited Plenary
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.
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Yannick Kluth (University of Toronto)01/09/2026, 16:30Invited Plenary
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...
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Oskar Stachowiak01/09/2026, 17:00Poster
We investigate a two-component Bose mixture with repulsive intra- and interspecies interactions in two and three spatial dimensions. In three dimensions, we analyse the global structure of the phase diagram, the order of the phase transitions, and the associated universality classes using mean-field theory and the functional renormalisation group. The system exhibits four distinct phases: a...
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Max Fornoville (Max Planck Institute for Solid State Research)01/09/2026, 17:01Poster
Dipolar interactions play an important role in the critical behavior of isotropic magnets. While the microscopic physics is usually dominated by short-range exchange interactions, dipolar interactions are strongly relevant in the RG sense due to their long-range nature, leading to a crossover from O(N) universality towards the dipolar fixed point, as pointed out by Aharony and Fisher in the...
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Johannes Pöplau01/09/2026, 17:02Poster
We investigate the Quark-Diquark Model (QDM) with the functional Renormalization Group (fRG) in the local potential approximation. In a recent work [arXiv:2510.01066 [hep-ph]], problems were reported in applying this method at low temperatures and large quark chemical potentials, which were attributed to numerical artifacts. In this work, we trace the origin of these problems to the occurrence...
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Konrad Kockler (Institut für Theoretische Physik, Universitat Heidelberg)01/09/2026, 17:03Poster
We present a self-consistent, manifestly Lorentz-invariant computation of real-time quark and meson spectral functions in the two-flavour Quark-Meson model, performed directly on the Minkowski axis using the spectral functional renormalisation group with emergent composites. The present work hosts two qualitative improvements over other spectral functional works so far. The first one is the...
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Patrick Niekamp (JLU Giessen)01/09/2026, 17:04Poster
Euclidean approaches such as the functional renormalization group (FRG) have been abundantly and successfully used to study the universal static critical behavior of various physical systems near continuous phase transitions. For the study of critical dynamics, on the other hand, one usually relies on real-time methods. This work illustrates the applicability and limitations of using Euclidean...
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Carlos Pastor Marcos (Institute for Theoretical Physics (ITP), Heidelberg University)01/09/2026, 17:05Poster
Effective field theories for cosmology offer a powerful framework to investigate the dynamics of space–time and address longstanding open puzzles. In this work, we initiate a programme to analyse the ultraviolet completion of vector–tensor quantum field theories within the asymptotic safety paradigm, focusing on generalised Proca theories with a vector condensate. This enables us to assess...
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Freddie Matthew King (University of Sussex)01/09/2026, 17:06Poster
Investigation of supposedly non-renormalisable four-fermion interactions using the FRG reveals non-trivial fixed points that recover predictivity. Scale-symmetry breaking and mass generation can be seen in Gross–Neveu theory, which involves only 'scalars' (ψbarψ). We extend these ideas to the Nambu-Jona-Lasinio model, which includes a 'pseudo-scalar' (ψγ5barψ) such that there is an overall...
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Lovro Šaravanja (Institute for Physics)01/09/2026, 17:07Poster
We investigate the probability distribution of the order parameter in the O(N) model, with a focus on its behavior near criticality. Characterizing the full distribution provides direct insight into fluctuations and universal features of the system.
On the analytical side, we employ the Functional Renormalization Group (FRG), which enables a non-perturbative treatment of critical...
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Tim Lukas Eckert (FSU Jena)01/09/2026, 17:08Poster
We investigate spontaneous symmetry breaking in a relativistic Yukawa theory with Luttinger fermions that exhibits self-organized criticality. Within the LPA' approximation, we numerically resolve the renormalization group flow of the full effective potential. We follow the flow from the symmetric phase, characterized by a partial fixed point, into the symmetry-broken phase. Featuring an...
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Gregorio Tibone (Côte d'Azur University, INPHYNI)01/09/2026, 17:10Poster
We study the shallow water model, which is a simplified model obtained from the Navier-Stokes equations by imposing the existence of a free surface and assuming the vertical height of the fluid to be small compared to the horizontal dimensions. This model allows to describe turbulent cascades in oceans near the coast or in highly stratified fluids. Moreover, the shallow water equations can be...
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Kanta Masuki (The University of Tokyo)01/09/2026, 17:11Poster
The renormalization group (RG) framework, which establishes a connection between a microscopic model at short distances and its coarse-grained counterpart at larger scales, has been a pivotal tool for understanding many-body phenomena across vastly different scales, ranging from elementary particles to condensed matter. Central to the RG's success is its multiscale nature, enabling systems...
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Yunxin Ye (FSU Jena)01/09/2026, 17:12Poster
We introduce a Yukawa model where a scalar boson interacts with both
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relativistic Luttinger fermions and Dirac fermions.
The Luttinger-Yukawa sector exhibits features similar to self-organized
criticality (SOC) which provides for a natural scale separation between an
initial UV scale and the scale of spontaneous symmetry breaking and mass gap
generation. We observe that the SOC... -
Alvaro Pastor Gutierrez (RIKEN iTHEMS)01/09/2026, 17:13Poster
Dynamical symmetry breaking plays a crucial role in mass and scale generation. In QCD-like theories, its dependence on the number of fermion flavours determines the phase structure and the transition to the conformal regime. In this work, we employ the functional renormalisation group and the generalised flow equation to compute non-perturbative corrections, including momentum dependencies and...
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Taichi Tanaka (Nihon University)01/09/2026, 17:14Poster
We formulate finite exact renormalization group (ERG) transformations on a multiply connected configuration space $Q$ by using the universal covering map $\pi:\widetilde Q\to Q$ and the Deck transformation group $\Gamma\cong\pi_1(Q,q_0)$. Following the broad definition used by Igarashi, Suzuki, and Sonoda, an ERG transformation is treated as a linear integral transformation acting on Boltzmann...
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Francesco Ferrarin (University of Copenhagen, Niels Bohr Institute)01/09/2026, 17:15Poster
Asymptotically safe quantum gravity has shown remarkable success when coupled to matter, notably yielding a successful postdiction of the top quark mass when the quantum gravity scale is identified with the Planck scale, a natural choice in a fundamental realization of Asymptotic Safety. This success raises the possibility that, even if not fundamental, asymptotically safe gravity may emerge...
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Justin Mauldin (Goethe University Frankfurt)01/09/2026, 17:16Poster
We investigate the Quark–Meson Model at finite temperature and chemical potential in the presence of an external magnetic field. Emphasis is placed on the effects of (inverse) magnetic catalysis on the structure of the phase diagram. In particular, we analyze how strong magnetic fields modify the emergence and geometry of the so-called moat regime, where nontrivial dispersion relations signal...
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Rory Phipps (University of Sussex)01/09/2026, 17:17Poster
Cosmological first-order phase transitions generate a stochastic background of gravitational waves (GWs), a measurement of which would signal physics beyond the Standard Model. A crucial quantity that enters the computation of the GW power spectrum is the bubble nucleation rate, which is accessible from the underlying QFT. At small coupling, the rate can be computed in perturbation theory....
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01/09/2026, 18:00
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Fabian Rennecke (University of Giessen)02/09/2026, 09:00Invited Plenary
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,...
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Gergely Fejos (Eötvös University Budapest)02/09/2026, 09:30Invited Plenary
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...
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Roman Zwicky (Edinburgh University)02/09/2026, 10:00Invited Plenary
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,...
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Prof. Ginestra Bianconi (Queen Mary University of London)02/09/2026, 11:00Invited Plenary
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...
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Marc Schiffer (Radboud University)02/09/2026, 11:30Invited Plenary
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...
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02/09/2026, 12:00
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Johanna Borissova (Imperial College London)02/09/2026, 14:00Talk
$2$-dimensional dilaton theories play a central role in discussions of black holes in a variety of approaches to classical and quantum gravity. In this talk I will present a unified framework for black hole thermodynamics of $d$-dimensional static black holes with spherical, toroidal or compact hyperbolic horizon topology satisfying $g_{tt}g_{rr}=-1$ in Schwarzschild gauge by considering the...
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Takato Mori (Rikkyo University)02/09/2026, 14:00Talk
Renormalization group (RG) flow has been discussed widely from high energy physics to statistical mechanics. However, the connection between many-body RG and continuum RG such as Wilsonian RG and functional/exact RG is not always clear. Moreover, once we consider a finite system, the RG process becomes approximate although several independent proposals have exist in the condensed matter...
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Alvaro Pastor Gutierrez (RIKEN iTHEMS)02/09/2026, 14:00
Precondensation is a peculiar phenomenon in phase transitions, characterised by the occurrence of a condensate only over a finite range of length scales. It is closely connected to the emergence of domains, pseudo-gapped phases and spatial inhomogeneities in equilibrium. In this talk, I will discuss its occurrence in gauge-fermion theories in the chiral limit, close to the thermal chiral phase...
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Nikolaos Tetradis (National and Kapodistrian University of Athens (GR))02/09/2026, 14:20Talk
I discuss the entanglement entropy for a free scalar field within a spherical region in various gravitational backgrounds (flat, de Sitter and anti-de Sitter space, the Einstein universe). In the first part I focus on the structure of the divergences. Universal coefficients are determined for ultraviolet and infrared divergent terms. In the second part I discuss the use of the finite part of...
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Gian Paolo Vacca (INFN - Bologna section)02/09/2026, 14:20Talk
Adopting the principles of minimal sensitivity we analyze, using the Wetterich Morris RG flow equations for various truncation schemes, the critical exponents of the 3-dimensional Ising universality class.
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Katsumi Itoh (Niigata University)02/09/2026, 14:20Talk
We consider quantum electrodynamics with chiral four-Fermi interactions in the functional renormalization group approach. In gauge theories, the functional flow equation for the effective action is accompanied by the quantum master equation that governs the underlying gauge symmetry. Beyond perturbation theory, fully gauge-consistent solutions are very difficult to obtain. By including the...
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Lucien Heurtier (King's College London)02/09/2026, 14:40Talk
In this talk, I will present a non-perturbative framework that allows to track the dynamics of slow-roll inflation while consistently incorporating quantum corrections, based on an alternative functional renormalisation group (RG) approach. I will guide you through the derivation of a set of coupled Friedmann-RG flow equations governing the joint evolution of spacetime, the inflaton field, and...
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Adam Rançon (Université de Lille)02/09/2026, 14:40Talk
The Ising model at criticality is a paradigmatic example of random variables displaying strong correlations at all scales. In the high and low temperature phases, the collective properties of the system are described by the standard (Gaussian) central limit theorem. In contrast, at the critical point separating the two phases, the fluctuations are non-Gaussian and are captured by a...
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Hao-Lin Li (Sun Yat-Sen University)02/09/2026, 14:40Talk
The infrared structure of gauge theories with chiral fermions remains largely unexplored. In this work we investigate the Bars-Yankielowicz class using the functional renormalisation group, building on recent developments in gauge-fermion systems that provide clear criteria for confinement and dynamical symmetry breaking. We show that two distinct phases arise: one exhibiting both confinement...
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Ugo Mire02/09/2026, 15:00
Diquarks, correlated quark-quark pairs carrying net color charge, play a key role in both baryon structure and dense quark matter. In this talk I will present results for the vacuum properties of the scalar diquark in a self-consistent and first-principles approach to QCD. Using the functional renormalization group, in particular dynamical hadronization, I will show how the high energy quark...
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Prof. Sarben Sarkar (King's College London)02/09/2026, 15:00Talk
The conjecture by two of the authors (N.E.M. and S.S.) that a \cPT-symmetric phase plays a role in understanding singular renormalisation group (RG) flows for a Chern-Simons (CS) gauge theory of axions, has been reexamined and significantly improved.
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We have used the more complete Wetterich equation, which includes gravitational couplings in a systematic way from the start, to... -
Mr Nicolas Paris (LPTMC Sorbonne Université)02/09/2026, 15:00Talk
Quantum impurity models are key platforms for studying strong electronic correlations and can be realized with high precision in quantum-dot experiments. While the low-transparency (weak-coupling) regime is well understood—particularly using the Numerical Renormalization Group—the opposite limit of highly transparent contacts has remained largely unexplored.
In this talk, I show how the...
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Eric Oevermann (Friedrich Schiller University Jena)02/09/2026, 15:20Talk
We study QCD in 1+1 dimensions focusing on meson formation in the vacuum. Utilizing a mass-like Callan-Symanzik regulator, we investigate the flow of the four-quark vertex in a Fierz complete basis. The couplings diverge in the point-like limit, signaling bound state formation. We progress with resolving some momentum dependencies by invoking a Hubbard-Stratonovich transformation. For heavy...
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Fabian Wagner (Heidelberg University)02/09/2026, 15:20Talk
Scalar-tensor theories are ubiquitous in cosmology. Asymptotic safety offers a guiding principle to significantly shrink the available theory space. At the same time, cosmological observables provide a stringent test of the asymptotic-safety paradigm. Focusing on Horndeski models of dark energy, I show how simple models fail to meet both observational constraints and constraints from...
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Ashutosh Dash02/09/2026, 15:20Talk
The functional renormalization group (FRG) recasts the flow of the effective action as an initial-value problem in RG "time," which for O(N)-type models can be written as a nonlinear fluid-dynamic conservation law for the field-space derivative of the potential. Physical observables - the IR vertex functions $\Gamma^{(2n)} = \partial_\sigma^{2n-1}u|_{\sigma=0}$ - are highly localized...
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Massimiliano Gubinelli (University of Oxford)02/09/2026, 16:10Invited Plenary
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.
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Dr Lingxiao Wang (RIKEN)02/09/2026, 16:40Invited Plenary
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...
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Dr Kevin Falls02/09/2026, 17:10Invited Plenary
In this talk I will discuss a new approach to classical general relativity.
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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... -
Astrid Eichhorn03/09/2026, 09:00Talk
I will review developments on the asymptotically safe Standard Model, in which an ultraviolet completion of the Standard Model with gravity may give rise to emergent structures in the Standard-Model couplings, which compare well with observed structures.
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Prof. Wei-jie Fu (Dalian University of Technology)03/09/2026, 09:00
The density functional renormalization group (density-fRG) is proposed to investigate the density fluctuations within the functional renormalization group approach, which allows us to quantify the medium effect and study physics of high densities. This method is applied to the nucleon-meson effective field theory, also known as the Walecka model, to study the properties of nuclear matter at...
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Alessandro Codello (Ca' Foscari)03/09/2026, 09:00Talk
We show that it is possible to use dimensional regularization (DR) beyond the usual $\varepsilon$-expansion in the context of renormalization group (RG) calculations in Critical Phenomena.
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Based on this fact, we propose a new functional RG scheme - Functional Dimensional Regularization (FDR) - and apply it to a scalar theory in three dimensions.
We compute the critical exponents of the... -
Prof. Brian Dolan (Dublin Institute for Advanced Studies)03/09/2026, 09:20Talk
The RG flow of the CKM matrix in the Standard model will be presented and the fixed points found. There are six fixed points, associated with the elements of the symmetric group of three objects, $S_3$. A proof is given that these are fixed points to all orders in perturbation theory and even non-perturbatively. The analysis is equally applicable to the PMNS matrix in the leptonic sector,...
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Piero Beretta (Facultad de Ingeniería. Universidad de la República)03/09/2026, 09:20Talk
The novel functional dimensional regularization (FDR) scheme has proven capable of yielding results that are competitive with the state-of-the-art in the computation of critical exponents in $d=3$, while also reproducing those from the $\varepsilon$-expansion for the Ising and other universality classes. In this work, we show that this is not a mere coincidence: by applying the scheme to the...
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Franz Richard Sattler (University Bielefeld)03/09/2026, 09:20
QCD at large densities exhibits a moat regime in the scalar-pseudoscalar sector. The resolution of its dynamics is pivotal to access the onset of new phases, including the potential critical endpoint of QCD.
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I report on a first self-consistent analysis of this regime, using the first-principles functional renormalisation group approach to QCD.
Mapping out the moat regime, we find a potential... -
Gonzalo De Polsi03/09/2026, 09:40
The derivative expansion is a central approximation scheme within the functional renormalization group, yet its convergence is often hindered by a strong dependence on the choice of regulator.
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In this talk, we argue that this limitation originates from the incomplete realization of conformal symmetry at criticality within standard projection procedures. To address this issue, we construct a... -
Zois Gyftopoulos (Heidelberg University)03/09/2026, 09:40Talk
Neutrinos oscillate with large mixing angles. Dirac neutrino masses are small
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compared to the other Standard Model fermions and a near-degenerate mass spectrum
is compatible with experimental data on neutrino masses. However, large mixing is not
radiatively stable in the near-degenerate case. Here, we find that the Standard Model lies
close to a transition between a phase with large and a... -
Chuang Huang (Heidelberg University, ITP)03/09/2026, 09:40
We present the first functional QCD calculation of the pion distribution amplitude (DA) using the large-momentum effective theory in the functional renormalization group (fRG) framework. With only the strong coupling and current quark masses as input, we compute the quasi-DA from first-principles QCD correlation functions. By pushing the pion momentum up to $P_z = 4.5\ \mathrm{GeV}$, the...
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Bernd-Jochen Schaefer03/09/2026, 10:00
Astrophysical observations of massive neutron stars and compact-object mergers increasingly point toward the presence of deconfined quark matter at high densities. In such environments, quarks are expected to form color-superconducting diquark pairs. Their properties are typically modeled within effective theories, where parameter fixing remains challenging due to the absence of diquarks as...
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Dr Shunsuke Yabunaka (ASRC, JAEA)03/09/2026, 10:00Talk
Renormalization group (RG) fixed points are commonly associated with scale invariance and a divergent correlation length. We show that this connection can fail in the tricritical O(N) model in three dimensions in the limit N→∞. Revisiting the line of fixed points identified by Bardeen, Moshe, and Bander, we use the functional renormalization group to clarify the mechanism leading to mass...
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Daniele Rizzo (KBFI-Tallinn)03/09/2026, 10:00Talk
We derive quantum gravity contributions to the beta functions of the gauge and Yukawa couplings of a matter theory using the Schwinger proper-time flow equation. Working in the Einstein-Hilbert truncation, we investigate the gauge-fixing and regulator dependence of the corresponding renormalization group equations. We quantify the sensitivity of our results on unphysical parameters by...
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Fanny Eustachon (École polytechnique)03/09/2026, 11:00Talk
The multicritical generalizations of the Lee-Yang universality class arise as RG fixed points of scalar field theories with complex $i\phi^{2n+1}$ interaction, just below their upper critical dimension. It has been recently conjectured that their continuation to two dimensions corresponds to the non-unitary conformal minimal models M(2,2n+3). Motivated by that, I will revisit the functional...
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Gabriel Assant03/09/2026, 11:00Talk
Using modern functional renormalisation adapted for theories in Lorentzian signature, and enhanced by new symmetry conditions to account for underlying Ward identities, we derive and solve flow equations directly for the Källén-Lehmann representation of propagators. Consistent results are found for several sets of renormalisation conditions yielding normalisable spectral functions for the...
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Sankarshan Sahu (LPTMC, Sorbonne Université)03/09/2026, 11:00Talk
The Central Limit Theorem does not hold for strongly correlated stochastic variables, as is the case for statistical systems close to criticality. Recently for the three-dimensional Ising model, the calculation of the probability distribution function (PDF) of the total spin: $P(L^{-d}\int d^{d}x~\phi(x)=s)$ at criticality has been performed with the functional renormalization group. It has...
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Bilal Hawashin03/09/2026, 11:20Talk
It was recently established that spontaneous symmetry breaking (SSB) can persist at all temperatures in certain quantum field theories (QFTs) that involve two scalar fields. This construction is based on the existence of a suitable fixed point, promoting the QFT to a conformal field theory (CFT) and thereby ensuring that the theory is well-defined in the high-temperature limit. In my...
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Ms Semanti Dutta (S.N. Bose National Center for Basic Sciences)03/09/2026, 11:20Talk
There is a method for constructing from first principles, a holographic bulk dual action in Euclidean $AdS_{d+1}$ space for a $d$-dimensional Euclidean CFT on the boundary, starting from the Polchinski's Exact RG (ERG) equation that describes the RG evolution of the interaction part of the boundary Wilson action. The bulk action in $AdS_{d+1}$ has an $SO(1,d+1)$ symmetry and is obtained from...
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Angelo Portas Chiesa (University of Sussex)03/09/2026, 11:20Talk
Asymptotically safe quantum gravity provides a UV completion of metric quantum gravity, with and without matter. This is achieved via scale invariance in the strongly coupled regime, entailing finiteness at all scales. Compared to the existence of the scaling symmetry, the study of the unitarity of the theory is still in its infancy. In this talk, I present the asymptotically safe scattering...
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Nicolás Wschebor (Instituto de Física de la Facultad de Ingeniería, Udelar (Uruguay))03/09/2026, 11:40Talk
We will present the “Derivative Expansion” as applied to the study of scalar models with $O(N)\times O(2)$ symmetry. These models describe Stacked Triangular Antiferromagnets, which have been the subject of a long-standing controversy regarding the order of the phase transition for the experimentally studied cases $N=2$ and $N=3$ in $d=3$. A brief review will be given of previous studies of...
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Alfiia Mukhaeva (Joint Institute for Nuclear Research)03/09/2026, 11:40Talk
From the locality condition of quantum field theory and the Bogoliubov-Parasiuk-Hepp-Zimmerman procedure, we will derive universal expressions that allow summation of complete series of singularities and logarithms in quantum field theory. To demonstrate, we will apply this approach to an effective theory with arbitrary scalar potential, where we sum the leading and subleading logarithmic corrections.
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Diego Buccio (Heidelberg University)03/09/2026, 11:40Talk
In higher derivative (HD) theories, a new kind of infrared divergences emerges from loop integrals. While in ordinary 2-derivative theories in d=4 IR divergencies are associated with the emission of soft or collinear particles by almost on-shell external legs, in HD theories IR divergencies are also observed in far off-shell processes. For this reason, the usual procedure of reabsorbing IR...
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Saswato Sen (Okinawa Institute of Science and Technology)03/09/2026, 12:00Talk
We investigate the critical behavior of a family of $\mathbb{Z}_2$-symmetric scalar field theories on the Bethe lattice (the tree limit of regular hyperbolic tessellations) using both the non-perturbative Functional Renormalization Group and lattice perturbation theory. The family is indexed by the parameter $\zeta \in (0,1]$, which determines the range of the theory via the kinetic term...
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Denis Tolkachev (Joint Institute for Nuclear Research)03/09/2026, 12:00Talk
As has recently been shown, the approach of summing logarithmic quantum corrections based on the locality of quantum field theory leads to sets of linear differential equations. Sometimes, obtaining such equations is a hard task. Since renormalizable quantum field theory has Callan-Symanzik renormalization group equation, we can apply a linearization procedure that allows us to determine these...
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Facundo Gutierrez (Universidad de la Republica, Uruguay)03/09/2026, 12:00Talk
The increasing precision of gravitational-wave observations demands analytical frameworks capable of accurately describing the relativistic dynamics of compact binaries beyond standard perturbation theory. While post-Newtonian and post-Minkowskian expansions have been highly successful, their intrinsically perturbative nature limits their applicability in strongly relativistic regimes.
In...
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Léonie Canet (Université Grenoble Alpes)04/09/2026, 09:00Invited Plenary
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...
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Vladimir Rosenhaus04/09/2026, 09:301Invited Plenary
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...
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Chiu Fan Lee (Imperial College London)04/09/2026, 10:00Invited Plenary
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...
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Yuto Ashida (The University of Tokyo)04/09/2026, 11:00Invited Plenary
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...
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Jan M. Pawlowski04/09/2026, 11:30Invited Plenary
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
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(ii) use the fact that the layerwise or even global... -
Chris Hooley (Coventry University)04/09/2026, 12:00Invited Plenary
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...
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04/09/2026, 12:30
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Kilian Fraboulet04/09/2026, 14:00Talk
Conventional implementations of the functional renormalization group (fRG) rely on regulators for bare propagators only, notably in the framework of the Wetterich equation. Starting from Schwinger-Dyson and Bethe-Salpeter equations, we develop an fRG formulation where both bare propagators and bare interactions can be dressed with regulators. This makes the resulting fRG setup more flexible,...
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Takeru Yokota04/09/2026, 14:00Talk
Although the formulation of the FRG is exact, practical calculations must be carried out approximately. This is because solvers for functional differential equations (FDEs), such as the Wetterich equation, have not yet been established. Meanwhile, physics-informed neural networks (PINNs) have recently gained attention as an efficient method for solving high-dimensional partial differential...
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Liubov Gosteva (UGA)04/09/2026, 14:00Talk
The Kuramoto-Sivashinsky (KS) equation describes various phenomena that exhibit instabilities, such as flames and reaction-diffusion systems. It resembles another famous non-equilibrium stochastic model - the Kardar-Parisi-Zhang (KPZ) equation, the main difference being the negative "viscosity" in the KS equation.
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It is known that the KS equation falls into the KPZ universality class, that... -
Tilman Enss (Heidelberg University)04/09/2026, 14:20Talk
We study critical phenomena in one-dimensional systems with long-range (LR) interactions, with a focus on the crossover to short-range universality. Employing functional renormalization group calculations and large-scale Monte Carlo simulations of self-avoiding Lévy flights on a 1D lattice, we determine the anomalous dimension η, the correlation length exponent ν, and the susceptibility...
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Hannes Braun (Technische Universität München, Max Planck Institute for Solid State Research)04/09/2026, 14:20Talk
We develop a functional renormalization group (fRG) framework for two-dimensional Hubbard models whose fermions carry two independent flavor quantum numbers transforming under SU(N) and SU(M), respectively. Exploiting the product-group structure, we show that the two-particle vertex decomposes exactly into two independent scalar functions, reducing the one-loop flow to a closed system of...
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Yang-yang Tan04/09/2026, 14:20Talk
We employ deep neural networks to represent the field derivative of the scale-dependent effective potential in the functional renormalization group (fRG) framework for nonperturbative quantum field theory. By embedding the fRG flow equations directly into the loss function, the network parameters are determined so as to provide a continuous and differentiable representation of the scale- and...
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Dr Laura Batini04/09/2026, 14:40Talk
We develop a perturbative renormalization-group framework for dynamical critical theories that interpolates between overdamped and propagating dynamics. Although the formalism includes the purely dissipative Model-A limit as a special case, our main focus is the opposite regime, where dissipation is weak or absent and the dynamics is dominated by second-order time derivatives.
Within the...
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Andras Laszlo (HUN-REN Wigner Research Centre for Physics (HU))04/09/2026, 14:40Talk
In Euclidean signature, we show that under mild conditions a nonterminating Wilsonian renormalization group (RG) flow of Feynman measures has a factorization property: there exists a regularization-independent ultimate Feynman measure (UV limit), from which the flow originates via pushforward (marginal) by the regulators. In addition, we prove certain existence theorems on the UV limit...
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Richard Schmidt (Institute for Theoretical Physics, Heidelberg University, Germany)04/09/2026, 14:40Talk
In this talk I will discuss how the functional renormalization group (FRG) can be employed to study strongly interacting Bose-Fermi mixtures and, in particular, to predict and characterize mechanisms of boson-induced superconductivity. I will begin by reviewing how a self-consistent FRG framework captures the quantum phase transition from a polaronic condensate to a molecular Fermi gas...
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Prof. Stefan Floerchinger (University of Jena)04/09/2026, 15:00Talk
Functional renormalization group flow equations can be constructed to be ultraviolet finite but break reflection positivity / unitarity, or vice versa. We explore how this problem can be circumvented with flow equations of second or higher order. They respect unitarity and are ultraviolet finite, but their solution leaves certain integration constants open. We discuss the physical significance...
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Andreas Rückriegel (Frankfurt University)04/09/2026, 15:00Talk
At strong on-site repulsion U, the fermionic Hubbard model realizes an extremely correlated electron system. In this regime, it is natural to derive the low-energy physics with the help of non-canonical operators acting on a projected Hilbert space without double occupancies. Using a strong-coupling functional renormalization group technique, we study the physics of such extreme correlations...
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Olivier Coquand (LAMPS/University of Perpignan)04/09/2026, 15:00Talk
Depsite being ubiquitous in the universe, plasmas still remain today a quite mysterious state of matter. Among the difficulties describing them is the fact that, even when they are dilute, the Coulomb interaction between electrons and ions is a long-range strong force.
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In this talk, we show how the fRG tools can be used to get a better understanding of the interactions between structures at... -
Riccardo Finotello (CEA Paris-Saclay)04/09/2026, 15:20Talk
Detecting signals within nearly continuous spectra remains a fundamental challenge in statistical inference, particularly in high-noise regimes where standard random matrix theory approaches, such as the Baik-Ben Arous-Péché (BBP) transition, frequently fail. We introduce a methodology that bridges statistical mechanics and statistical inference. By treating the empirical spectrum as an...
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Dr Thomas Sheerin (University of St Andrews)04/09/2026, 15:20Talk
The engineering of exotic ordered states in two-dimensional itinerant electron systems is a matter central to the field of quantum materials, from the viewpoints of both fundamental physics and applications. Ordinary Van Hove singularities (VHSs), logarithmic divergences in the density of states arising from quadratic saddle points in a material’s dispersion, have long been known to induce...
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Antal Jakovác (Wigner Research Centre for Physics)04/09/2026, 15:20Talk
The conventional picture of the renormalization-group (RG) flow is that of a smooth evolution in coupling space, which becomes approximately linear in the vicinity of fixed points. In this framework, relevant and irrelevant directions are identified through the scaling properties of perturbations around the fixed point.
However, there are important physical situations in which the RG...
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Christopher Herzog04/09/2026, 16:10Invited Plenary
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...
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Dr Enrico Pajer (University of Cambridge)04/09/2026, 16:40Invited Plenary
Cosmological observables of the primordial universe are encoded in the late-time field-theoretic wavefunction. I begin with a pedagogical review of the constraints on the wavefunction imposed by fundamental principles such as unitarity, locality, and causality. I then show that for shift-symmetric scalars in de Sitter - an excellent approximation for many inflationary models - the wavefunction...
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Christof Wetterich05/09/2026, 09:30Invited Plenary
We propose that quantum gravity may predict the Fermi scale.
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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... -
Neil Turok (University of Edinburgh)05/09/2026, 10:00Invited Plenary
Quadratic gravity (QG) is an attractively minimal framework for quantum gravity, being renormalizable and asymptotically free. In a certain limit, the only nontrivial degree of freedom is the conformal factor of the metric. The Lorentzian theory is nevertheless rich enough to describe both a cosmological background and particle-like excitations within it. Both are governed by a four-derivative...
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Prof. Tim Morris (University of Southampton)05/09/2026, 11:00Invited Plenary
We show that the derivative expansion of the exact (functional)
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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... -
Friederike Ihssen (ITP Heidelberg)05/09/2026, 11:30Invited Plenary
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...
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Holger Gies (FSU Jena)05/09/2026, 12:00Invited Plenary
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...
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