Significant progress has been made since pioneering work concerning the characterization of asteroids in distinctive classes according to the features found in their reflectance spectra. Part of that progress comes from the parallel study of meteorites in our laboratories because they represent samples of their parent bodies. In particular, the so-called carbonaceous chondrites are undifferentiated meteorites that come from primitive asteroids and probably comets. They contain significant amounts of organic matter and water, but their physical and reflective properties are still largely unknown. We are suspicious that they come from dark bodies formed in the outer region of the protoplanetary disk, where they were accreted from diverse components: crystalline and amorphous minerals, organics and volatile species. There is growing interest about these research lines because dark and primitive asteroids are future targets of space based missions like e.g. OSIRIS-REx or Hayabusa (respectively of NASA and JAXA space agencies). The cosmochemical and astrobiological clues require their successful remote characterization, and establishing clear associations with meteorite analogs that has remained in most cases elusive. Asteroids of the C spectral class, which are the targets of the next round of sample return missions, are mostly characterized by their low albedos, and flat, mostly featureless spectra. We plan to study their association with different groups of carbonaceous chondrites available in IEEC-CSIC laboratories in a spectral window from UV to mid-IR. In conclusion, we plan to study the physical properties of chondrites in order to infer new clues on the properties of primitive asteroids, and better understand the continuous decay of comets. One of our goals is increasing our understanding about the hazard associated with the impact of these objects in the atmosphere of Earth.
The physics of extremely hot and/or dense relativistic plasmas is extremely rich. Quantum field theory computations for these systems have revealed to be cumbersome, as the standard quantum loop expansion valid at zero temperature ceases in this case to correspond to a gauge coupling constant expansion. In these plasmas there is a well-defined hierarchy of energy scales, defined by the temperature and/or chemical potential, as well as derived energy scales, obtained by multiplying the above by the gauge coupling constant. This fact gives the basic playground to use effective field theory techniques. In this thesis we will use and develop effective field theory techniques for the study of hot and/or dense plasma, and show how one can compute many properties of theses plasmas at high accuracy. Applications of these methods for both astrophysical and cosmological settings will be addressed.