Benjamin L'Huillier

Cosmologist & Astrophysicist at Sejong University, Seoul, Korea

A Little About Me

A French cosmologist in South Korea

I am an Assistant Professor in the Department of Physics and Astronomy at Sejong University in Seoul, South Korea. From June 2019, I hold a research grant from the National Research Foundation.

My research interests focus on falsifying different aspects of the concordance LCDM model using N-body simulations within and beyond LCDM, and advanced statistical methods. I am also a member of the DESI collaboration, involved in the time domain and the cosmological simulations working groups.

I completed my PhD at LERMA , Paris Observatory and Université Pierre et Marie Curie, working in the Galaxies and Cosmology group with Françoise Combes and Benoit Semelin, and a member of the Momentum project. I was also a Teaching Assistant at the Université Paris Diderot, where I taught Physics and data analysis.

After that, I moved to South Korea, a growing hub for research, in particular in Astronomy and Cosmology, and I became a Research Fellow in the Astrophysics and Cosmology group of the Korea Institute for Advanced Study (KIAS) in Seoul with Profs. Changbom Park and Juhan Kim on cosmological structure formation, from galaxies to the large-scale structures of the Universe, using numerical simulations such as the Horizon Run 4 simulation. I then moved to the CosKASI group at the Korea Astronomy and Space Science Institute in Daejeon where I was working with Arman Shafieloo. I then became a  Research Professor and W. C. Rufus Fellow working in the Yonsei Observable UNiverse Group (YOUNG) 


  • 2020-12-15: Paper on Negative Cosmolgical Constant accepted in PRD 

  • 2020-09-28: Hanwool Koo's paper on Model selection and parameter estimation using the iterative smoothing method on arXiv:2009.12045

  • 2020-08-25: New paper on a negative cosmological constant in the dark sector on arXiv:2008.10237 

  • 2020-06-30~2020-11-30: I am co-organizing the Dark Energy in a Dark Age online lecture series at APCTP, please check out the webpage. Lecture are also uploaded to youtube 

  • 2020-05-24: Press release about the VLBI measurement of cosmic distances in Hankyoreh (in Korean)

  • 2020-03-23: Paper proposing a new method to measure cosmic distances to AGN via VLBI with Jeff Hodgson accepted in MNRAS (2003.10278)

  • 2020-01-29: Hanwool Koo's paper on model-independent analysis of JLA SNIa on arXiv:2001.10887

  • 2019-10-03: Paper on non-linear dark energy perturbations with F. Hassani, A. Shafieloo, M. Kuntz and J. Adamek on arXiv (1910.01105)

  • 2019-06-17: paper on reconstructing the expansion from growth data on arXiv (1906.05991)

  • 2019-06-01 ~ 2022-05-31: NRF Grant (~150kUSD): "Testing the cosmological model with the large-scale structures"

  • 2019-05-27: paper on "debiaising gravitational sirens"on arXiv (1905.10216)

  • 2019-02-22 : Paper on systematics in the Pantheon compilation accepted in MNRAS 485, 2783 (2019)

Contact Information

Department of Physics and Astronomy

Sejong University

Gwangjin-gu, Neungdong-ro 209
South Korea

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