Search for dissertations about: "Spacetimes"

Showing result 6 - 10 of 18 swedish dissertations containing the word Spacetimes.

  2. 6. On the asymptotics of Bianchi class A spacetimes

    Author : Hans Ringström; KTH; []
    Keywords : Mixmaster; cosmic censorship; cosmology;

    Abstract : .... READ MORE

  4. 7. 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

  5. 8. Strong Cosmic Censorship and Cosmic No-Hair in spacetimes with symmetries

    Author : Katharina Maria Radermacher; Hans Ringström; James Isenberg; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Cosmic Censorship; Cosmic No-Hair; Big Bang; symmetry; Bianchi; T2-symmetry; Gowdy; general relativity; cosmology; late time; initial time; asymptotic behaviour; perfect fluid; scalar field; Einstein equations; Mathematics; Matematik;

    Abstract : This thesis consists of three articles investigating the asymptotic behaviour of cosmological spacetimes with symmetries arising in Mathematical General Relativity.In Paper A and B, we consider spacetimes with Bianchi symmetry and where the matter model is that of a perfect fluid. READ MORE

  6. 9. On Curvature-Free Connections and Other Properties of the Lanczos Spinar

    Author : Fredrik Andersson; James Vickers; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : In this thesis we study various properties of the Lanczos spinor. The results include an algebraic classification scheme for symmetric (3,1)-spinors, a link between Lanczos potentials of the Weyl spinor and the spin coefficients in certain classes of spacetimes, an existence proof for the Lanczos potential of a general Weyl candidate that is much simpler than those previously known and the existence of a symmetric potential HABA'B' of an arbitrary symmetric (3,1)-spinor LABCA' in Einstein spacetimes according tothe equation LABCA' = ∇(AB' HBC)A'B'. READ MORE

  7. 10. The Chevreton tensor and its trace

    Author : Ingemar Eriksson; Marc Mars; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; MATHEMATICS; MATEMATIK;

    Abstract : In this thesis we investigate the Chevreton tensor in Einstein-Maxwell theory. It was introduced in 1964 as the counterpart, for electromagnetic fields, of the well-known Bel-Robinson tensor of the gravitational field. We prove that, in the absence of electromagnetic sources, this tensor is completely symmetric. READ MORE