Gilles Fontaine (1948 – November 1, 2019) was a professor of astrophysics at the Université de Montréal in Quebec, Canada. Fontaine's research interests included theoretical and observational studies of white dwarfs, sub-dwarf stars and astroseismology (the interpretation of variations in brightness of certain pulsating or vibrating stars to understand their interior structure). In particular, he found that white dwarfs can serve as test benches for the equation of state, the coefficient of transport, and the phase transition between solid and liquid states at very high densities. Source: Wikipedia (en)