Timo Kist
PhD candidate at Leiden Observatory
Timo Kist
Welcome!
Scroll down to find out more about me and my research
I'm a PhD candidate at Leiden Observatory in the ENIGMA group of Joe Hennawi, working at the intersection of theory and observation, as well as statistics and machine learning.
I'm currently working on modeling techniques as well as a statistical inference framework to constrain the Epoch of Reionization with quasar IGM damping wings. In the past, I've also been contributing to very different topics in theoretical cosmology and condensed matter theory.
When did Reionization occur?
My PhD research revolves around the question of when and how reionization occurred, probed by the damping wing signature imprinted upon the spectra of high-redshift quasars by the foreground neutral intergalactic medium (IGM). I'm working on a state-of-the-art Bayesian inference pipeline, coded fully differentiably in the machine learning framework JAX. I'm also concerned with modeling techniques, and I've recently established a new set of damping wing summary statistics that carry information about the local ionization topology in front of a quasar, allowing for constraints on both timing and topology of reionization.
My academic trajectory
Growing up in a small town in Northern Germany, I soon became interested in mathematics
and (natural) sciences, and year by year, I took part in the Mathematical
Olympiad in Göttingen. This inspired me to start my undergraduate studies at
the University of Göttingen, and I completed them with two Bachelor degrees,
one in Physics, and one in Mathematics.
I spent the first year of my Master studies abroad in Helsinki, Finland, where
Christian Flindt and Jose Lado gave me the opportunity to gain my first
cutting-edge research experience at Aalto University in condensed matter theory.
Upon returning to Germany, I completed my Master's project in the field of theoretical
cosmology with Anna Ijjas at the Max Planck Institute for Gravitational Physics
in Hanover, concluding my time in Göttingen with a Master's degree in Theoretical
Physics. In 2022, I moved on to Leiden Observatory, Netherlands, for my PhD studies in
Joe Hennawi's ENIGMA group.
Leiden Observatory
🇳🇱
August 2022 - July 2026
PhD candidate in Astronomy
Advisor: Joe Hennawi
Max Planck Institute
for Gravitational Physics
🇩🇪
April 2021 - March 2022
Master thesis student
Advisor: Anna Ijjas
Aalto University
🇫🇮
May 2020 - July 2020
Summer research intern
Advisors: Christian Flindt and Jose Lado
University of Helsinki
🇫🇮
August 2019 - May 2020
Erasmus exchange student
Master’s Program in Particle Physics and Astrophysical Sciences
University of Göttingen
🇩🇪
September 2016 - March 2022
Master of Science in Theoretical Physics
Bachelor of Science in Mathematics
Bachelor of Science in Physics
My publications
- Timo Kist, Joseph F. Hennawi, Frederick B. Davies, Eduardo Bañados, Sarah E. I. Bosman, Zheng Cai, Anna-Christina Eilers, Xiaohui Fan, Zoltán Haiman, Hyunsung D. Jun, Yichen Liu, Jinyi Yang and Feige Wang: First constraints on the local ionization topology in front of two quasars at z ~ 7.5, submitted to MNRAS
- Timo Kist, Joseph F. Hennawi and Frederick B. Davies: Inferring local quasar IGM damping wing constraints, submitted to MNRAS
- Timo Kist, Joseph F. Hennawi and Frederick B. Davies: A local, topology-independent parameterization of quasar IGM damping wings, submitted to MNRAS
- Joseph F. Hennawi, Timo Kist, Frederick B. Davies and John Tamanas: Precisely measuring the cosmic reionization history from IGM damping wings towards quasars, MNRAS (2025), 539, 2621
- Timo Kist, Joseph F. Hennawi and Frederick B. Davies: Quantifying the precision of IGM damping wing measurements towards quasars, MNRAS (2025), 538, 2704
- Timo Kist and Anna Ijjas: The robustness of Slow Contraction and the shape of the scalar field potential, Journal of Cosmology and Astroparticle Physics 8 (2022) 046
- Timo Kist, Jose Lado and Christian Flindt: Lee-Yang theory of criticality in interacting quantum many-body systems, Physical Review Research 3, 033206 (2021)