My research is within the field of stellar astrophysics, in particular in the study of white dwarfs. White dwarfs are the endpoints of the lives of the vast majority of stars after they have finished their nuclear reactions and lost their outer layers. With roughly half the mass of the Sun and the size of the Earth, white dwarfs are extremely dense and hence have properties unlike anything we find in our solar system. Thus, for example, if a white dwarf exceeds a certain mass limit it explodes as a type Ia supernovae, thermonuclear explosions that have been used for proving the accelerated expansion of the Universe. Moreover, because they simply cool down, we can derive the ages of white dwarfs from their temperatures and surface gravities. When a white dwarf is in a binary system that evolved avoiding mass transfer interactions we can thus derive the age of the companion star as well. Because of these properties, white dwarfs and white dwarfs in binaries are ideal tools for studying a wide diversity of open problems in modern astrophysics, a research line that I have successfully followed during my entire career.
In particular, my current research focuses on tackling the following relevant issues of the maximum interest: 1) Does the age-metallicity relation in the Galactic disk exist?; 2) What are the properties of the age-velocity dispersion relation in the Galactic disk?; 3) How do close compact binaries evolve?; 4) What are the progenitors of type Ia supernovae?; 5) What is the origin of the observed excess of massive white dwarfs?; 6) How well constrained are the physical models of white dwarfs and low-mass main sequence stars? For answering these questions I am using the combined wealth of information that ongoing surveys provide together with follow-up observations performed at the best telescopes around the globe and a detailed theoretical modeling of the observational data.