Search for dissertations about: "gravitational"

Showing result 1 - 5 of 162 swedish dissertations containing the word gravitational.

  2. 1. Gravitational collapse in bimetric gravity

    Author : Marcus Högås; Edvard Mörtsell; Tomi Koivisto; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Bimetric gravity; bigravity; modified gravity; gravitational collapse; Bimetrisk gravitation; modifierad gravitation; gravitationskollaps; teoretisk fysik; Theoretical Physics;

    Abstract : Einstein’s theory of general relativity has been the prevailing theory of classical gravity for over a century. Its observational consistency is unparalleled. There are however a few (arguably) serious short-comings. READ MORE

  4. 2. Gravitational perturbations in plasmas and cosmology

    Author : Mats Forsberg; Gert Brodin; Michael Bradley; Christopher Clarkson; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; 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

  5. 3. Supernovae seen through gravitational telescopes

    Author : Tanja Petrushevska; Rahman Amanullah; Ariel Goobar; Saurabh Jha; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; supernovae; strong gravitational lensing; star formation history; supernova rates; supernovor Gravitationslins; fysik; Physics;

    Abstract : Galaxies, and clusters of galaxies, can act as gravitational lenses and magnify the light of objects behind them. The effect enables observations of very distant supernovae, that otherwise would be too faint to be detected by existing telescopes, and allows studies of the frequency and properties of these rare phenomena when the universe was young. READ MORE

  6. 4. Investigating the Dark Universe through Gravitational Lensing

    Author : Teresa Riehm; Ariel Goobar; Edvard Mörtsell; Erik Zackrisson; Joachim Wambsganss; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; cosmology; gravitational lensing; dark matter; galaxies; galaxy clusters; Astronomy; Astronomi; Astronomy; astronomi;

    Abstract : A variety of precision observations suggest that the present universe is dominated by some unknown components, the so-called dark matter and dark energy. The distribution and properties of these components are the focus of modern cosmology and we are only beginning to understand them. READ MORE

  7. 5. Was Einstein Wrong? : Theoretical and observational constraints on massive gravity

    Author : Marcus Högås; Edvard Mörtsell; David Mota; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Gravity; Massive gravity; Bimetric gravity; Cosmology; Gravitational collapse; Gravitational waves; Observational constraints; Theoretical Physics; teoretisk fysik;

    Abstract : For more than a century, Einstein's theory of general relativity has described gravitational phenomena with astonishing precision. However, for the theory to fit observations we need to add two elusive substances: dark energy and dark matter. Together they add up to 95% of the energy budget of the Universe. READ MORE