• Numerical calculation of Casimir forces 

      Kilen, Isak Ragnvald (Master thesis; Mastergradsoppgave, 2012-06-19)
      In this thesis a set of regularized boundary integral equation are introduced that can be used to calculate the Casimir force induced by a two dimensional scalar field. The boundary integral method is compared to the functional integral method and mode summation where possible. Comparisons are done for the case of two parallel plates, two concentric circles and two adjacent circles. The results ...
    • On elementary particles as representations of the Poincaré group 

      Martínez Marín, Pau (Master thesis; Mastergradsoppgave, 2023-08-14)
      This thesis is concerned with the definition of elementary particles as irreducible projective unitary representations of the Poincaré group. During the contents of this work, we will introduce the relevant prerequisites and results. Concerning differential geometry, we will discuss smooth manifolds, Lie groups and Lie algebras. About quantum mechanics, we will introduce Hilbert spaces and the basic ...
    • On the effects of symmetry in the energy balance on a sphere 

      Samuelsberg, Aksel (Mastergradsoppgave; Master thesis, 2022-05-15)
      Simple climate models have gathered much attention as they have suggested the possibility of abrupt climate change associated with tipping points. Several simple climate models are found to have multiple equilibria, but in most cases similar equilibria do not appear or become too difficult to find in complex, fully coupled earth system models. In this thesis, we investigate a simple climate model, ...
    • On the Ewald-Oseen scattering formulation for linear and nonlinear transient wave scattering 

      Kuzmina, Anastasiia (Master thesis; Mastergradsoppgave, 2017-05-16)
      In this thesis work we develop and apply EOS formulation to three scattering problems: two of them are 1D problems and one is 2D. The first chapter comprises EOS formulations and numerical implementation for 1D scattering problems. Also in this chapter we use different numerical methods to solve test problem and choose the most stable and accurate method for solving of the given 1D problems. ...
    • Real Plane Algebraic Curves 

      González García, Pedro (Master thesis; Mastergradsoppgave, 2021-06-18)
      This master thesis studies several properties of real plane algebraic curves, focusing on the case of even degree. The question of the relative positions of the connected components of real plane algebraic curves originates in Hilbert's sixteenth problem which, despite its prominence, is still open in the case of higher degree curves. The goal of this thesis is an exposition of fundamental ...
    • Separable representations of the Poisson, Helmholtz and complex Helmholtz kernels 

      Bjørgve, Magnar (Master thesis; Mastergradsoppgave, 2017-02-15)
      For high accuracy applications of integral operators in higher dimensions the complexity of operation and storage usually grows exponentially with dimensions. One method that has proven successful for handling these difficulties are the separation of the integral kernels as linear combinations of products of one-dimensional kernels, commonly referred to as separation of variables. In this ...
    • Simplicial complexes, Demi-matroids, Flag of linear codes and pair of matroids. 

      Zubair, Ali (Master thesis; Mastergradsoppgave, 2015-05-15)
      We first describe linear error-correcting codes, and show how many of their most important properties are determined by their associated matroids . We also introduce the simplicial complex of the independent sets of a matroid. We then proceed to study flags of linear codes, and recall the definition of demi-matroids, and how such demi-matroids associated to flags can describe important properties ...
    • Symmetric Ideals 

      Lien, Arne (Mastergradsoppgave; Master thesis, 2021-05-14)
      Polynomials appear in many different fields such as statistics, physics and optimization. However, when the degrees or the number of variables are high, it generally becomes quite difficult to solve polynomials or to optimize polynomial functions. An approach that can often be helpful to reduce the complexity of such problems is to study symmetries in the problems. A relatively new field, that has ...
    • Symmetry transformation groups and differential invariants 

      Schneider, Eivind (Master thesis; Mastergradsoppgave, 2014-11-15)
      There exists a local classification of finite-dimensional Lie algebras of vector fields in two complex dimensions. We lift the Lie algebras from this classification to three complex dimensions.
    • Tipping points and crises in financial markets 

      Shemyakina, Polina (Master thesis; Mastergradsoppgave, 2015-05-15)
      Electricity spot markets and other financial markets are complex systems, and it is difficult to forecast their behaviour, especially uncontrolled and unmanageable situations, such as power crises and deflation of financial bubbles. An energy crisis is any price rise in the supply of energy resources to an economy. It has undesirable consequences, occasionally irreversible. The most known of these ...
    • Towers of Betti Numbers of Matroids and Weight Distribution of Linear Codes and their Duals 

      Huerga Represa, Violeta (Master thesis; Mastergradsoppgave, 2015-05-15)
      The main notion behind the study of matroids is linear dependence. In this thesis, we give a survey of the concepts and properties of linear error-correcting codes over finite fields being dependent only on the matroids derived from these codes. In particular, the weight distributions of linear codes, and their extensions, over bigger fields are only dependent on the N-graded Betti numbers of these ...
    • The Unidirectional Pulse Propagation Equation for Cylindrical Vector modes 

      Nilsen, Vegard (Master thesis; Mastergradsoppgave, 2015-07-27)
      A new model for the unidirectional pulse propagation equations (UPPE) was developed by Per Jacobsen[1], this model is based on the assumption of cylindrical vector (CV) modes. The model will be strong for CV type electrical eld representations where only a few modes will be excited. In this thesis we will investigate the model further. The model will be implemented as a pseudo spectral method where ...
    • The use of elliptic curves in cryptography 

      Juhas, Tibor (Master thesis; Mastergradsoppgave, 2007-06)
      The use of elliptic curves in cryptography was suggested independently by Neal Koblitz and Victor Miller in 1985. Being a relatively new field, there is still a lot of ongoing research on the subject, but elliptic curve cryptography, or ECC for short, has already been implemented in real-life applications. Its strength was proved in 2003 when the U.S. National Security Agency adopted ECC for protecting ...
    • Wachpress Conjecture Restricted To Arrangements Of Three Conics 

      Schena, Alessandro (Mastergradsoppgave; Master thesis, 2022-05-15)
      This thesis discusses Wachpress conjecture restricted to arrangements of three conics. Wachpress conjectured the existence of a set of barycentric coordinates, namely Wachpress coordinates, on all polycons. Barycentric coordinates are very useful in many different fields as they can be used to define a finite element approximation scheme with linear precision. This thesis focuses on the conjecture ...