NuSym23, XIth International Symposium on Nuclear Symmetry Energy

Observed for the first time in 1967 as pulsars, neutron
stars represent the most extreme bodies known in our universe. Relict
of the gravitational collapse and subsequent supernova explosion of a
massive star at the end of his life, they gather a mass of up to twice
that of our sun in a sphere with a radius of about 10 km. Their
phenomenology is very rich and complex. Modelling requires many
different fields of physics such as general relativity, nuclear
physics and solid state physics. During this talk, after an
introduction, I will discuss some examples of how the confrontation of
observational data with neutron star models allows to probe properties
of ultra-dense and hot matter. Future prospects to improve our
understanding and in particular to pin down the potential existence of
a phase transition in dense matter with constraints from gravitational
wave detections will be discussed, too.