Sökning: "Hans Ringström"

Hittade 4 avhandlingar innehållade orden Hans Ringström.

  1. 1. Quiescent regimes in cosmology

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

    Sammanfattning : 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. LÄS MER

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

    Författare :Hans Ringström; KTH; []
    Nyckelord :Mixmaster; cosmic censorship; cosmology;

    Sammanfattning : .... LÄS MER

  4. 3. Strong Cosmic Censorship and Cosmic No-Hair in spacetimes with symmetries

    Författare :Katharina Maria Radermacher; Hans Ringström; James Isenberg; KTH; []
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

  5. 4. Future stability of the Einstein-Maxwell-Scalar field system and non-linear wave equations coupled to generalized massive-massless Vlasov equations

    Författare :Christopher Svedberg; Hans Ringström; Alan Rendall; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis consists of two articles related to mathematical relativity theory. In the first article we prove future stability of certain spatially homogeneous solutionsto Einstein’s field equations. The matter model is assumed to consist of an electromagnetic field and a scalar field with a potential creating an accelerated expansion. LÄS MER