Danish Quantum Field Theory Meeting 2025

13 Aug 2025, 09:30 → 14 Aug 2025, 16:00 Europe/Copenhagen

U220 (University of Southern Denmark)

From August 13-14, 2025, the Danish Quantum Field Theory Meeting 2025 will take place at the University of Southern Denmark, Odense. The aim of the meeting is to bring together researchers from Denmark and beyond working on various aspects of Quantum Field Theory. Topics will include scattering amplitudes, gravitational waves, gauge-gravity correspondence, string theory, mathematical physics, topological Quantum Field Theory, phenomenology and lattice Quantum Field Theory.

Registration for the event is open. As part of the registration, please indicate if you would like to contribute a presentation. If you register for the meeting, please be aware that there is only a limited number of seats in the room and we may not be able to accept all registrants. Please note that your participation is not confirmed, until you receive a confirmation email. 

The registration deadline for contributing presentations is June 30th, 2025.

The registration deadline for participation is July 31st, 2025.

Invited speakers 

• Emil Bjerrum-Bohr
• Benjamin Jäger
• Niels Obers
• Marta Orselli
• Alessia Platania
• Thomas Ryttov
• Konstantin Wernli

 

Organizers

• Roger Morales
• Florian Seefeld
• Matthias Wilhelm

 

Logistics

Anne Katrine Birch - birch@imada.sdu.dk

 

Sponsors

Poster.pdf

Wednesday 13 August

09:30 → 10:00 Registration and coffee

10:00 → 10:45 TBD

Speaker: Emil Bjerrum-Bohr

10:45 → 11:30 TBD

Speaker: Marta Orselli

11:30 → 12:00 Kerr Black Hole Dynamics from an Extended Polyakov Action

We examine a hypersurface model for the classical dynamics of spinning black holes. Under specific rigid geometric constraints, it reveals an intriguing solution resembling expectations for the Kerr Black three-point amplitude. We explore various generalizations of this formalism and outline potential avenues for employing it to analyze spinning black hole attraction.

Speaker: Gang Chen

12:00 → 13:00 Lunch break

13:00 → 13:30 TBD

Speaker: Nabha Shah

13:30 → 14:15 TBD

Speaker: Konstantin Wernli

14:15 → 14:45 Resurgence in Topological Quantum Field Theory

Resurgence is a method for summation of divergent power series. In recent years this have been succesfully applied to divergent series arising from pertubation theory in quantum field theory. I will illustrate this with the Witten-Reshetikhin-Turaev topological quantum field theory for a certain general class of three-manifold space-times. This is based on joint work with Andersen, Han, Li, Sauzin and Sun.

Speaker: William Mistegård

14:45 → 15:15 Coffee break

15:15 → 16:00 TBD

Speaker: Niels Obers

16:00 → 16:30 Boundary energy-momentum tensor for asymptotically flat spacetimes

I will discuss the construction of a boundary energy-momentum tensor for asymptotically flat spacetimes. This involves rewriting Einstein's equations in a way that is covariant with respect to the Carrollian boundary geometry and turns part of the Einstein equations into Ward identities for the Carrollian energy-momentum tensor. I will also discuss holographic renormalisation for asymptotically flat spacetimes. This provides new insights into a putative holographic description of flat spacetime in terms of a boundary Carrollian conformal field theory.

Speaker: Emil Have

16:30 → 17:00 Integrable corners in the space of Gukov-Witten defects

Integrability of planar N=4 super-Yang-Mills (SYM) theory enables exact computations of unprotected observables, even with the insertion of certain extended operators. While integrability techniques have been successfully applied to some supersymmetric domain walls and line defects, it is an open question whether there are any integrable surface defects in N=4 SYM theory. In this talk, I will examine a class of 1/2-BPS surface defects known as Gukov-Witten defects. I will argue that these defects are generically not integrable but they are likely to become integrable at a corner in parameter space. I will present closed-form factorised expressions for leading-order one-point functions of unprotected scalar operators, hinting at the possibility of finding an all-loop formula at this special point.

Speaker: Adam Chalabi

18:30 → 20:30 Conference dinner - Storms Pakhus

Thursday 14 August

09:45 → 10:15 Welcome and coffee

10:15 → 10:45 TBD

Speaker: Giulia Muco

10:45 → 11:30 TBD

Speaker: Alessia Platania

11:30 → 12:00 TBD

Speaker: Florian Seefeld

12:00 → 13:00 Lunch break

13:00 → 13:45 TBD

Speaker: Benjamin Jaeger

13:45 → 14:15 Gradient flow as a renormalization tool

The Gradient Flow is a smoothing technique that has been extensively studied for its renormalization properties. When combined with the short flow-time expansion, it provides a renormalization scheme in which hadronic matrix elements on the lattice evolve with the flow time, suppressing ultraviolet (UV) divergences. In this scheme, some of the typical lattice challenges—such as operator mixing with lower-dimensional operators—are either avoided or relegated to the perturbative matching stage. I will begin by introducing the Gradient Flow methodology and provide an overview of the short flow-time expansion. I will then present our approach for determining two distinct classes of observables: (1) matrix elements of four-quark operators relevant to neutral meson mixing and meson lifetimes, and (2) renormalized quark masses.

Speaker: Antonio Rago

14:15 → 14:45 The Brief Femtouniverse

No technique used to compute observables, such as the 1/N-expansion or the bootstrap method, is successful for QCD. A method which should work, at least in principle, is a semiclassical van-Vleck formula, applied to the femtouniverse: a small region of Euclidean space-time. This yields a renormalization-group transformation to a lattice model which should be a correct description of the continuum field theory at large distances. To test the method, we apply it to the (well-understood) O(3) nonlinear sigma model in two dimensions.

Speaker: Peter Orland

14:45 → 15:15 Coffee and departure