Sökning: "NATURAL SCIENCES Physics Astronomy and astrophysics Cosmology"
Visar resultat 1 - 5 av 136 avhandlingar innehållade orden NATURAL SCIENCES Physics Astronomy and astrophysics Cosmology.
1. Gravitational perturbations in plasmas and cosmology
Sammanfattning : Gravitational perturbations can be in the form of scalars, vectors or tensors. This thesis focuses on the evolution of scalar perturbations in cosmology, and interactions between tensor perturbations, in the form of gravitational waves, and plasma waves. LÄS MER
2. Searches for Particle Dark Matter : Dark stars, dark galaxies, dark halos and global supersymmetric fits
Sammanfattning : The identity of dark matter is one of the key outstanding problems in both particle and astrophysics. In this thesis, I describe a number of complementary searches for particle dark matter. LÄS MER
3. Supersymmetry vis-à-vis Observation : Dark Matter Constraints, Global Fits and Statistical Issues
Sammanfattning : Weak-scale supersymmetry is one of the most favoured theories beyond the Standard Model of particle physics that elegantly solves various theoretical and observational problems in both particle physics and cosmology. In this thesis, I describe the theoretical foundations of supersymmetry, issues that it can address and concrete supersymmetric models that are widely used in phenomenological studies. LÄS MER
4. Spectral Properties of Type Ia Supernovae and Implications for Cosmology
Sammanfattning : Type Ia supernovae can, for a short period of time, reach the same brightness as an entire galaxy. They are responsible for the creation of a large fraction of all heavy elements and can be used, as standard candles, to prove that the expansion of the universe is accelerating. Yet, we do not fully understand them. LÄS MER
5. Magnetic fields around massive protostars as traced by masers and dust emission
Sammanfattning : It is not fully clear how the magnetic field acts during the first stages of star formation. A possible way to clarify its role is to observe the polarized light coming from masers and thermal dust emission. LÄS MER