Search for dissertations about: "Symmetry and equations"

Showing result 1 - 5 of 54 swedish dissertations containing the words Symmetry and equations.

  2. 1. Real and complex Monge-Ampère equations, statistical mechanics and canonical metrics

    Author : Jakob Hultgren; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Statistical Mechanics; Point Processes; Hessian manifolds; Kähler geometry; Optimal Transport; Canonical metrics; Complex Monge-Ampère equations; Real Monge-Ampère equations; Kähler-Einstein metrics; Statistical Mechanics;

    Abstract : Recent decades has seen a strong trend in complex geometry to study canonical metrics and the way they relate to geometric analysis, algebraic geometry and probability theory. This thesis consists of four papers each contributing to this field. The first paper sets up a probabilistic framework for real Monge-Ampère equations on tori. READ MORE

  4. 2. Polynomial Solvers for Geometric Problems - Applications in Computer Vision and Sensor Networks

    Author : Yubin Kuang; Matematik LTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; polynomial solver; geometric problems; computer vision; sensor networks; symmetry;

    Abstract : Given images of a scene taken by a moving camera or recordings of a moving smart phone playing a song by a microphone array, how hard is it to reconstruct the scene structure or the moving trajectory of the phone? In this thesis, we study and solve several fundamental geometric problems in order to provide solutions to these problems. The key underlying technique for solving such geometric problems is solving systems of polynomial equations. READ MORE

  5. 3. 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. 4. Analysis of Planar and Circular Cylindrical Multilayer Structures with Application to Soft and Hard Surfaces

    Author : Zvonimir Sipus; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; antennas; periodic surfaces; integral equations; approximate boundary conditions; soft and hard surfaces; Green s functions; corrugated surfaces; moment method; periodic metal strips; multilayer structures; EFIE; microstrip antennas; spectral domain analysis; group representation theory; strip scatterers;

    Abstract : This thesis deals with the analysis of planar and circular cylindrical multilayer structures, such as strip-loaded dielectric layers, corrugated surfaces and microstrip antennas. In particular, we study corrugations and strip-loaded grounded dielectric slabs when they are used to realize soft and hard surfaces. READ MORE

  7. 5. Spontaneous and stimulated X-ray Raman scattering

    Author : Yu-Ping Sun; Faris Gel'mukhanov; Vincenzo Carravetta; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; resonant X-ray scattering; resonant Auger scattering; rotational Doppler broadening; XFEL pulse; Atomic and molecular physics; Atom- och molekylfysik; Spectroscopy; Spektroskopi;

    Abstract : The present thesis is devoted to theoretical studies of resonant X-ray scattering and propagation of strong X-ray pulses. In the first part of the thesis the nuclear dynamics of different molecules is studied using resonant X-ray Raman and resonant Auger scattering techniques. READ MORE