Search for dissertations about: "cosmological perturbations"

Showing result 1 - 5 of 7 swedish dissertations containing the words cosmological perturbations.

  2. 1. Effects of the Higgs field on Inflation and Reheating

    Author : Aliki Litsa; Katherine Freese; Jens Jasche; Stockholms universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; inflation; reheating; Higgs; non-gaussianity; cosmological perturbations; Theoretical Physics; teoretisk fysik;

    Abstract : The model of inflation - a period of accelerated expansion in the very early Universe - was introduced to give solutions to a number of problems encountered in the Standard Big Bang paradigm. Additionally, due to its quantum nature, inflation is able to generate the necessary primordial inhomogeneity “seeds”, which eventually evolve into large-scale structures. READ MORE

  4. 2. Searches for Particle Dark Matter : Dark stars, dark galaxies, dark halos and global supersymmetric fits

    Author : Pat Scott; Joakim Edsjö; Lars Bergström; Jan Conrad; Dan Hooper; Stockholms universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; dark matter; supersymmetry; gamma rays; dwarf galaxies; stellar evolution; cosmological perturbations; phase transitions; statistical techniques; Astroparticle physics; Astropartikelfysik; Astroparticle physics; Astropartikelfysik; Cosmology; Kosmologi; Elementary particle physics; Elementarpartikelfysik; Computational physics; Beräkningsfysik; Formation and development of stars; Stjärnors bildning och utveckling; High energy astrophysics; Högenergiastrofysik; teoretisk fysik; Theoretical Physics;

    Abstract : 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. READ MORE

  5. 3. Gravitational perturbations in plasmas and cosmology

    Author : Mats Forsberg; Gert Brodin; Michael Bradley; Christopher Clarkson; Umeå universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; general relativity; cosmology; gravitational waves; plasma; electromagnetic waves; nonlinear waves; Plasma physics; Plasmafysik; Theory of relativity; gravitation; Relativitetsteori; gravitation; Cosmology; Kosmologi; teoretisk fysik; Theoretical Physics;

    Abstract : 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. READ MORE

  6. 4. Perturbative Methods in General Relativity

    Author : Daniel Eriksson; Michael Bradley; Gert Brodin; Lászlo Árpád Gergely; Umeå universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; General relativity; perturbation theory; photon-photon scattering; cosmology; FRW models with cosmological constant; Bianchi type V; slowly rotating stars; Hartle formalism; Physics; Fysik;

    Abstract : Einstein's theory of general relativity is a cornerstone in the process of gaining increased understanding about problems of gravitational nature. It can be applied to problems on the huge length scales of cosmology and as far as we know it does not break down before the Planck scale is approached. READ MORE

  7. 5. Rotating relativistic models of the universe : construction and interpretation

    Author : Egils Sviestins; Stockholms universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : This thesis summarizes and gives the background to some accompanying papers dealing with the following problems.Some cosmological models, e.g. that of Gödel, indicate that there is a connection between rotation and the existence of causality violating closed time-like curves. READ MORE