Sökning: "cosmological constants"
Hittade 5 avhandlingar innehållade orden cosmological constants.
1. Cosmological constants galore
Sammanfattning : .... LÄS MER
2. Cosmological aspects of universal extra dimensions
Sammanfattning : It is an intriguing possibility that our world may consist of more than three spatial dimensions, compactified on such a small scale that they so far have escaped detection. In this thesis, a particular realization of this idea -- the scenario of so-called 'universal extra dimensions' (UED) -- is studied in some detail, with a focus on cosmological consequences and appplications. LÄS MER
3. New horizons in string theory : bubble babble in search of darkness
Sammanfattning : It was discovered nearly two decades ago that we live in an accelerating universe that is dominated by dark energy. Understanding the origin of such an energy has turned out to be a very difficult open question in physics, and calls on the need for a fundamental theory like string theory. LÄS MER
4. From Metric to Connection. Actions for Gravity, with Generalizations
Sammanfattning : The search for a theory of quantum gravity has for a long time been almost fruitless. A few years ago, however, Ashtekar found a reformulation of Hamiltonian gravity, which thereafter has given rise to a new promising quantization project; the canonical Dirac quantization of Einstein gravity in terms of Ashtekar's new variables. LÄS MER
5. Measurements of High-Precision Atomic Data with Applications to Astrophysics and Cosmology
Sammanfattning : Investigations of astrophysical spectra require accurate atomic data, such as wavelengths and transition probabilities. This thesis provides high-precision atomic data for astrophysical and cosmological applications. The measurements have been carried out using Fourier transform spectrometry on light produced in a hollow cathode light source. LÄS MER