Search for dissertations about: "Cosmology"

Showing result 21 - 25 of 519 swedish dissertations containing the word Cosmology.

  2. 21. Quiescent regimes in cosmology

    Author : Hans Oude Groeniger; Hans Ringström; Mattias Dahl; Todd Oliynyk; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; quiescence; Bianchi spacetimes; big bang formation; G2 cosmology; Wainwright-Hsu variables; Klein-Gordon equation; Matematik; Mathematics;

    Abstract : This thesis is about cosmological solutions to Einstein’s equations of general relativity, in particular spacetimes whose mean curvature diverges. Moreover, we consider anisotropic spacetimes with big bang singularities. In this setting the singularity is expected to generically be oscillatory if no matter is present. READ MORE

  4. 22. How ISM properties drive Lyman Continuum Escape

    Author : Johannes Puschnig; Matthew Hayes; Göran Östlin; Rahman Amanullah; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astrophysics; Cosmology; Extragalactics; Reionization; Lyman Continuum; Interstellar Medium; ISM; Tololo 1247-232; Astronomy; astronomi;

    Abstract : The thesis introduces physical processes that are at work in astrophysical plasmas and reviews the current state of research related to the emission of ionizing photons, i.e. Lyman continuum (LyC). Star forming galaxies and active galactic nuclei are discussed as sources of LyC. READ MORE

  5. 23. Tests for systematic effects in supernova cosmology

    Author : Serena Nobili; Ariel Goobar; Bruno Leibundgut; Stockholms universitet; []
    Keywords : Cosmology; supernovae; astrophysics;

    Abstract : Type~Ia supernovae are used as standard candles to measure the energy density components of the universe. This led to the new paradigm in cosmology: only about 30\% of the universe is made by ordinary pressure-less matter, the rest is associated with an unknown form of energy with a negative equation of state parameter, called dark energy, able to drive the accelaration of the universe. READ MORE

  6. 24. String Theory at the Horizon : Quantum Aspects of Black Holes and Cosmology

    Author : Martin Olsson; Ulf Danielsson; Lárus Thorlacius; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Theoretical physics; theoretical physics; string theory; black holes; cosmology; de Sitter space; c=1 matrix models; 2D string theory; topological string theory; conifolds; 4D BPS black holes; Gödel universe; closed time-like curves; Teoretisk fysik; Physics; Fysik;

    Abstract : String theory is a unified framework for general relativity and quantum mechanics, thus being a theory of quantum gravity. In this thesis we discuss various aspects of quantum gravity for particular systems, having in common the existence of horizons. READ MORE

  7. 25. Antimatter and cosmology

    Author : Ernest M. Svaton; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : .... READ MORE