since April 2015, I am a full professor at TTK (the Institute of Particle Physics and Cosmology of the RWTH Aachen University).
You can email me at: Julien.Lesgourgues _at_ physik.rwth-aachen.de
or write me at: TTK, Sommerfeldstr. 16, 52074 Aachen, Germany
or call me at: +49 241 80 25734 or +49 241 80 27046 (secretaries), +49 241 80 25724 (direct)
or fax me at: +49 241 80 22187
or find me in MBP 105, Modulbau 1 Physik, Otto-Blumenthal-Str., Melaten Campus, Aachen
I am a researcher in cosmology, the area of physics devoted to the
understanding of our universe's global properties and evolution.
This vast field lays at the interface between
theoretical physics, particle physics and astrophysics.
My original background is rather in theoretical physics, but as time passed by, I got
closer and closer to astrophysics, with a particular interest for the theoretical interpretation
of astrophysical observations relevant for
cosmology and particle physics. I am a member of the
collaboration and of the Euclid satellite collaboration.
I am specialized in modeling the evolution of cosmological
perturbations, starting from their generation (presumably during a
stage in the early universe called inflation). Cosmological
perturbations are responsible for cosmic microwave background
anisotropies and for the formation of the large scale structure of the
universe. Observing these quantities allows cosmologists to derive
bounds and constraints on cosmological parameters, and on various
possible extensions of the minimal cosmological scenario.
These issues are intimately related to the dark matter and dark energy
problems, as well as other fascinating questions like the role of
neutrinos in cosmology, or like possible observable consequences of
high energy physics models (supersymmetry, string theory, large extra
dimensions, modifications of gravity...)