ERG 2022

Session

Poster

25 Jul 2022, 17:20

Description

Dimitrios Gkiatas

118. A study of a toy model of hydrodynamic turbulence using the NPRG

Côme Fontaine

25/07/2022, 17:20

The functional renormalisation group has already been successfully used to study turbulence and it appears as a very natural tool for this problem. However, there remains an unsolved problem related to the calculation of the structure functions in the turbulent state, which is hard to tackle directly from the Navier-Stokes equations. In this work, we study a simpler model: the Sabra shell...

111. Asymptotic freedom and safety in quantum gravity

Saswato Sen

25/07/2022, 17:20

We compute non-perturbative flow equations for the couplings of quantum gravity in fourth order of a derivative expansion. The gauge invariant functional flow equation for arbitrary metrics allows us to extract β-functions for all couplings. In our truncation we find two fixed points. One corresponds to asymptotically free higher derivative gravity, the other is an extension of the...

107. Asymptotically safe Einstein-Palatini gravity

Abdol Sabor Salek

25/07/2022, 17:20

87. Background Effective Action with Nonlinear Massive Gauge Fixing

Dimitrios Gkiatas

25/07/2022, 17:20

121. Dilaton Quantum Gravity

Athanasios Kogios

25/07/2022, 17:20

In this presentation, I will talk about asymptotically safe dilaton gravity. To that end we solve the coupled set of flow equations for the field dependent Newton constant F(phi), cosmological constant or dilaton potential V(phi) and dilaton wave function K(phi), including the physical vanishing cutoff scale. At vanishing dilaton field we recover classical general relativity, while we approach...

99. Entangled magnetic, charge, and superconducting pairing correlations in the 2-D Hubbard model

Sarah Heinzelmann

25/07/2022, 17:20

96. EOS of QCD Matter

Andreas Geissel

25/07/2022, 17:20

115. Fluctuation computation of gravitational RG flows on foliated spacetime

Jian Wang

25/07/2022, 17:20

The exact renormalization group is a powerful tool to explore the renormalization group fixed points in gravity and gravity-matter systems. An important open question in this context is the extension of the formalism to Lorentzian signature computations. One way to incorporate the necessary structures in the presence of a fluctuating spacetime is the Arnowitt-Deser-Misner decomposition of the...

89. FRG analysis of the pseudogap opening in the 2D Hubbard model at finite doping

Hannes Braun

25/07/2022, 17:20

We apply the functional renormalisation group to the two-dimensional Hubbard model to investigate the pseudogap opening. Extending previous applications at half filling [Phys. Rev. Research 2, 033068 (2020)], we here explore the physics in the more relevant finite-doping regime. In particular, we present a systematic analysis of the different contributions to the self-energy by performing a...

95. FRG based on the single boson exchange decomposition

Kilian Fraboulet

25/07/2022, 17:20

113. From KPZ to Inviscid Burgers universality : a FRG approach

Francesco Vercesi

25/07/2022, 17:20

In one dimension, the stochastic Burgers’ equation, describing a randomly forced viscous fluid, can be obtained from the Kardar-Parisi-Zhang (KPZ) equation for a stochastically growing interface through an exact mapping. Since its introduction, the KPZ equation has been studied broadly, and found to successfully describe the universal dynamics of a wide range of systems out of equilibrium,...

104. Functional Renormalization for Multimatrix Models

Carlos I. Perez Sanchez

25/07/2022, 17:20

In this poster we report recent progress in understanding the algebraic structure underlying Wetterich Equation for multimatrix models (this sort of model is inspired by noncommutative geometry and contains interactions indexed by the free algebra, i.e. words in the random matrices). The tools can be useful in discretization approaches to quantum gravity and combinatorics of maps. Based on...

110. Functional Spin RG for Rydberg Array Spin Hamiltonians

Benedikt Schneider

25/07/2022, 17:20

Rydberg-Atom arrays are a versatile platform to simulate interesting physics from spin liquids to lattice gauge theories. We develop a one-loop functional renormalization group approach based on Kitaev's pseudo-Majorana spin representation that produces quantitative accurate data for Rydberg type Hamiltonians at finite temperature. By using the convenient symmetries of the Majorana...

92. Holographic RG from Exact RG

Pavan Dharanipragada

25/07/2022, 17:20

Holographic RG is the interpretation of the AdS-CFT correspondence as RG evolution of boundary theory. The radial coordinate is interpreted as the scale of the boundary theory. This allows a new physical way of looking at the correspondence. But, the precise regularisation of the boundary theory that allows this interpretation hasn't been looked at. I will show one such regularisation using...

91. Incommensurate 2kF density wave quantum criticality

Lukas Debbeler

25/07/2022, 17:20

98. Information theoretic regulators for complex systems with multiple notions of scale

Adam Kline

25/07/2022, 17:20

88. mfRG analysis of the Attractive Hubbard Model

Aiman Al-Eryani

25/07/2022, 17:20

97. Multiloop functional renormalization group study of the Fermi polaron problem

Marcel Gievers

25/07/2022, 17:20

Imbalanced mixtures of strongly correlated fermions have been investigated both theoretically and experimentally for several decades. A single impurity immersed in a Fermi gas is subject to a transition from a bound molecule of two different fermion species to a so-called ‘Fermi polaron’ where the impurity forms a quasiparticle with the surrounding fermions [1]. We study the Fermi polaron...

109. Phase Transitions in Yukawa Models

Richard Schmieden

25/07/2022, 17:20

119. Phonon renormalization and Pomeranchuk instability in the Holstein model

Max Oberon Hansen, Niklas Cichutek

25/07/2022, 17:20

The Holstein model with dispersionless Einstein phonons is one of the simplest models describing electron-phonon interactions in condensed matter. A naive extrapolation of perturbation theory in powers of the relevant dimensionless electron-phonon coupling suggests that at zero temperature the model exhibits
a Pomeranchuk instability characterized by a divergent uniform compressibility at a...

106. Real-time functional renormalization group for critical dynamics

Johannes Roth

25/07/2022, 17:20

Real-time quantities such as spectral functions and transport coefficients can serve to examine the real-time evolution of a system close to equilibrium, as they encode the possible excitations in the medium and show universal static and dynamic scaling behaviour near a critical point. The functional renormalization group (FRG) formulated on the Schwinger-Keldysh closed-time path provides an...

114. Shift-symmetric Horndeski models in the asymptotically safe swampland?

Fabian Wagner

25/07/2022, 17:20

Horndeski theories are widely considered extensions of general relativity, intended to explain the dark sector dynamically as well as alleviate the existing cosmological tensions. In this poster, I present a first renormalisation group analysis of the subclass of shift-symmetric kinetic braiding models, which still holds up to observation after GW170817. In particular, I show the four arising...

116. Spectral functions from renormalised flow equations

Jonas Wessely

25/07/2022, 17:20

We derive renormalized Callan-Symanzik Flowequations in the FRG setup and apply the framework of spectral renormalisation to compute the full, nonperturbative spectral function of a \phi^4 theory in (2+1) dimensions

103. SU(4) symmetry in Dirac materials - Application to twisted bilayer graphene

Nikolaos Parthenios

25/07/2022, 17:20

120. Symmetry constraints for Callan-Symanzik flows in chiral models

Sebastian Töpfel

25/07/2022, 17:20

112. The $( 1 + 1 )$-dimensional Gross-Neveu model at non-zero $\mu$, $T$ and finite $N$

Jonas Stoll

25/07/2022, 17:20

We investigate the Gross-Neveu model for a finite number of fermions $N$. The solution of the Gross-Neveu model is well known in the large-$N$ limit ($N \to \infty$) but unknown for finite $N$. We approach the finite-$N$ case with a FRG method, more precisely the Wetterich equation. By using the local potential approximation the resulting flow equation for the scale dependent effective...

117. The $( 1 + 1 )$-dimensional Gross-Neveu model at non-zero $\mu$, $T$ and finite $N$

Niklas Zorbach

25/07/2022, 17:20

We investigate the Gross-Neveu model for a finite number of fermions $N$. The solution of the Gross-Neveu model is well known in the large-$N$ limit ($N \to \infty$) but unknown for finite $N$. We approach the finite-$N$ case with a FRG method, more precisely the Wetterich equation. By using the local potential approximation the resulting flow equation for the scale dependent effective...

101. The F-theorem in the melonic limit

Davide Lettera

25/07/2022, 17:20

The F-theorem states that in three dimensions the sphere free energy of a field theory must decrease between ultraviolet and infrared fixed points of the renormalization group flow, and it has been proven for unitary conformal field theories (CFTs). We consider here the long-range bosonic O(N)3 model on a spherical background, at next-to-next-to-leading order of the 1/N expansion. The model...

102. The predictive power of asymptotic safety for an ALP model

Rafael Robson Lino dos Santos

25/07/2022, 17:20

An asymptotically-safe theory of quantum gravity could render a non-perturbative renormalization of general relativity, restoring its predictive power at higher energies. The asymptotic-safety community has been finding indications for that, mainly using the functional renormalization group framework. In this poster, I will explore the predictive power of asymptotically-safe quantum gravity...

108. Towards quantitative precision for non-smooth interaction potentials in FRG flows

Franz Richard Sattler

25/07/2022, 17:20

100. Truncated-unity FRG approach to minimal models of correlated moiré materials

ravn henkel

25/07/2022, 17:20

The functional renormalization group is a powerful tool to analyze many-body instabilities in strongly-correlated electron systems. In a simple but handy truncation scheme, i.e. the level-two truncation, it resolves the RG evolution of the two-particle interaction vertex. Thereby it manages to detect the leading instability of the electron system while taking into account all competing...

94. Universal scaling at a pre-thermal dark state

Tilman Enss

25/07/2022, 17:20

Many open quantum systems are well described by an effective non-hermitian Hamiltonian generating a time evolution that allows eigenstates to decay and dissipate to the environment. In this framework, quantum coherent scaling is traditionally tied to the appearance of dark states, where the effect of dissipation becomes negligible. Here we discuss the universal dynamical scaling after a sudden...

105. UV Conformal Window and Loss of Asymptotic Safety

Nahzaan Riyaz

25/07/2022, 17:20

90. G flows between Gaussian fixed points

Diego Buccio

A scalar theory can have many Gaussian (free) fixed points, corresponding to Lagrangians of the form \phi\box^k\phi. We use the non-perturbative RG to study the flow from the free theory with four derivatives (k = 2) to the free theory with two derivatives (k = 1), in the presence of a shift-invariant interaction.

122. P

93. P