Search for dissertations about: "Naturvetenskap Matematik Geometri"

Showing result 1 - 5 of 139 swedish dissertations containing the words Naturvetenskap Matematik Geometri.

  2. 1. Vector-valued Eisenstein series of congruence types and their products

    Author : Jiacheng Xia; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Hecke operator; Fourier expansion of modular forms; congruence type; products of Eisenstein series; vector-valued modular forms;

    Abstract : Historically, Kohnen and Zagier connected modular forms with period polynomials, and as a consequence of this association concluded that the products of at most two Eisenstein series span all spaces of classical modular forms of level 1. Later Borisov and Gunnells among other authors extended the result to higher levels. READ MORE

  4. 2. Topological and geometrical methods in data analysis

    Author : Oliver Gäfvert; Sandra di Rocco; Henry Schenck; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; multiparameter persistent homology; computational algebraic geometry; algorithms; complexity; Mathematics; Matematik;

    Abstract : This thesis concerns two related data analysis pipelines, using topological and geometrical methods respectively, to extract relevant information. The first pipeline, referred to as the topological data analysis (TDA) pipeline, constructs a filtered simplicial complex on a given data set in order to describe its shape. READ MORE

  5. 3. Admissible transformations and the group classification of Schrödinger equations

    Author : Celestin Kurujyibwami; Peter Basarab-Horwath; Roman Popovych; Pontelis Damianou; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : We study admissible transformations and solve group classification problems for various classes of linear and nonlinear Schrödinger equations with an arbitrary number n of space variables.The aim of the thesis is twofold. READ MORE

  6. 4. Positive vector bundles in complex and convex geometry

    Author : Hossein Raufi; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Nakano positivity; vanishing theorems; Prekopa theorem; Griffiths positivity; convex geometry; Ohsawa-Takegoshi extension theorem; dbar-equation; L^2-estimates; singular hermitian metrics; holomorphic vector bundles; holomorphic vector bundles; dbar-equation; L^2-estimates; singular hermitian metrics; Griffiths positivity; Nakano positivity; vanishing theorems; Ohsawa-Takegoshi extension theorem; convex geometry; Prekopa theorem;

    Abstract : This thesis concerns various aspects of the geometry of holomorphic vector bundles and their analytical theory which all, vaguely speaking, are related to the notion of positive curvature in general, and L^2-methods for the dbar-equation in particular. The thesis contains four papers. READ MORE

  7. 5. 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