Supervisors

• Prof. Dr. Alexandre Refregier, ETH Zürich
• Dr. Michele Bianco, ETH Zürich

Physics Departement – Cosmology Group
ETH Zürich

Can we use AI to model, where stars form?

In my master's thesis, I explore the application of AI to model and predict CDM density distributions inside ionized HII regions (bubbles) in the early universe.
The primary objective is to develop a flow-based generative model that takes a given ionized bubble as input and outputs a probabilistic density distribution of matter within that bubble. The model is trained using a dataset of bubble-density pairs, where each bubble corresponds to a 2D density slice extracted from high-resolution simulations using pyC2Ray. To achieve this, I employ normalizing flows (GLOW), which iteratively transform a simple base distribution (a Gaussian centered on the bubble) into the target density distribution.

Supervisors

• Prof. Dr. Philippe Jetzer, University of Zurich
• Prof. Dr. Gian Michele Graf, ETH Zürich

Physics Institute – Gravitation and Astrophysics Group
University of Zurich

Could the Moon serve as a giant gravitational wave detector and provide new confirmation of Einstein's General Relativity?

In this thesis, we review in detail the interaction between gravitational waves (GWs) and the Moon, treated as an elastic body, as presented in a paper by M. Kachelriess and M. P. Nødtvedt. The aim is, to combine the content of this paper with additional findings from previous literature to make the topic more accessible.
Building on the theoretical framework of elasticity, we derive and linearize Cauchy’s equations of motion to model the Moon’s response to such a GW. By investigating toroidal and spheroidal oscillations induced by a GW in different polarizations, we derive the differential equation systems to predict the Moon’s displacements, which can then be numerically solved. The results of different papers are summarized to get the eigenfrequencies and modes of these displacements. We furthermore provide some insights on frequency-dependent response.

Supervisors

• Prof. Dr. Matthias Gaberdiel, ETH Zürich
• Dr. Matthew Lewandowski, ETH Zürich

Physics Departement – String Theory Group
ETH Zürich

How can the geometry of string world-sheets unlock new insights into quantum scattering?

In this report, we explain how the world-sheet of a string can be viewed as a Riemann surface. This is essential when calculating quantum mechanical scattering amplitudes, which in string theory characterize the probability of different scattering occurring. In order to map the upper half-plane H¯ of the complex plane onto a polygon, the SchwarzChristoffel map is introduced. As a result, we can find a canonical representation of the world-sheet of three strings interacting by considering it as a degenerate polygon.