Sökning: "Massive gravity"
Visar resultat 1 - 5 av 23 avhandlingar innehållade orden Massive gravity.
1. Was Einstein Wrong? : Theoretical and observational constraints on massive gravity
Sammanfattning : 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. LÄS MER
2. Cosmic tests of massive gravity
Sammanfattning : Massive gravity is an extension of general relativity where the graviton, which mediates gravitational interactions, has a non-vanishing mass. The first steps towards formulating a theory of massive gravity were made by Fierz and Pauli in 1939, but it took another 70 years until a consistent theory of massive gravity was written down. LÄS MER
3. Gravitational collapse in bimetric gravity
Sammanfattning : 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. LÄS MER
4. Strings, Gravitons, and Effective Field Theories
Sammanfattning : This thesis concerns a range of aspects of theoretical physics. It is composed of two parts. In the first part we motivate our line of research, and introduce and discuss the relevant concepts. In the second part, four research papers are collected. LÄS MER
5. Geometry of interactions in ghost-free bimetric theory
Sammanfattning : The ghost-free bimetric theory is an extension to general relativity where two metric tensors are used instead of one. A priori, the two metrics may not have compatible notions of space and time, which makes the formulation of the initial-value problem problematic. LÄS MER
