# Lattice Field Theory

## HU+DESY Lattice Seminars

This seminar series is organised jointly by the NIC Research Group at DESY Zeuthen and the Theory of Elementary Particles and Computational Theoretical Physics research groups of the Institute for Physics at Humboldt University. For questions please contact Dr. Andreas Risch (DESY Zeuthen).

During the current semester, seminars are held virtually on Zoom generally on Mondays at 13:00 (some events may be scheduled at special times).

https://desy.zoom.us/j/85167662273
Meeting ID: 851 6766 2273
Passcode: 173979

In addition to this website, seminars will also be announced on the lat-bb mailing list.

For past events, visit the Indico page.

### Towards a holographic description of cosmology on the lattice

Speaker: Prof. Andreas Jüttner (University of Southampton)
Date: Monday, November 29, 2021
Time: 1:00 pm (Europe/Berlin)

Following a recent proposal based on holography the physics of the very early universe can be described in terms of a three-dimensional quantum field theory without gravity. In this model cosmological observables are expressed in terms of correlation functions of the energy-momentum tensor computed in the QFT. Testing the model against observational data, e.g. from Planck, requires control over the non-perturbative dynamics in the QFT, which we address with numerical simulations on the lattice. In this talk I will discuss our progress towards making predictions for the properties of the CMB from our model, which requires understanding the IR properties of 3d super-renormalisable QFT and the computation of 2pt functions of the energy-momentum tensor on the lattice.

### QED corrections to the hadron spectrum from lattice QCD with massive photons

Speaker: Prof. Nicholson, Amy (The University of North Carolina at Chapel Hill)
Date: Monday, December 6, 2021
Time: 3:00 pm (Europe/Berlin)

Lattice QCD calculations are beginning to push comparisons between theoretical and experimental tests of the Standard Model to unprecedented precisions. In order to meet this precision goal, QED effects must be introduced. In this talk, I will present a systematic study of the spectra of hadrons using a novel technique in which power-law finite-volume effects are mitigated through the introduction of a non-zero photon mass. I will show that the effects of zero-mode and other non-perturbative contributions may be fully accounted for within this framework, and explore an isospin breaking scheme in which electromagnetic and strong isospin breaking effects are separated at leading order.

### tba

Speaker: Mr Lücke, Jens (Humboldt-Universität zu Berlin)
Date: Monday, December 13, 2021
Time: 1:00 pm (Europe/Berlin)

### Rotated twisted-mass: a convenient regularization scheme for isospin breaking QCD and QED lattice calculations

Speaker: Dr Gagliardi, Giuseppe (Università degli studi di Roma Tre)
Date: Monday, January 10, 2022
Time: 1:00 pm (Europe/Berlin)

### Leading isospin breaking effects in the HVP contribution to $a_{\mu}$ and to the running of $\alpha_{\mathrm{em}}$

Speaker: Risch, Andreas (Z_ZPPT (Zeuthen Particle PhysicsTheory))
Date: Monday, January 17, 2022
Time: 1:00 pm (Europe/Berlin)

### tba

Speaker: Mr Rizik, Matthew (Michigan State University)
Date: Monday, January 24, 2022
Time: 3:00 pm (Europe/Berlin)

### tba

Speaker: Prof. Montangero, Simone (Università di Padova)
Date: Monday, January 31, 2022
Time: 1:00 pm (Europe/Berlin)