Essays about: "Dirac equation"

Showing result 1 - 5 of 9 essays containing the words Dirac equation.

  1. 1. Linear-scaling Quantum Molecular Dynamics for Reactive Systems

    University essay from Uppsala universitet/Institutionen för informationsteknologi

    Author : Linnéa Andersson; [2021]
    Keywords : ;

    Abstract : The purpose of this thesis is to demonstrate linear-scaling, energy stable, propagation of the electronic degrees of freedom in finite temperature ExtendedLagrangian Born-Oppenheimer Molecular Dynamics for reactive systems in aself-consistent charge density-functional tight-binding formulation. The inverse Jacobian kernel matrix in the electronic equation of motion is approximated using alow-rank combination of directional derivatives of the ground state residual function. READ MORE

  3. 2. The Ratio of Reality : A study of the gyromagnetic ratio in theories ranging from classical mechanics to string theory

    University essay from Uppsala universitet/Teoretisk fysik

    Author : Daniel Nilsson; [2021]
    Keywords : Quantum field theory ; String theory ; Dirac equation ; Dirac theory ; Dirac; gyromagnetic; ratio; g-factor; Kvantfältsteori; strängteori; Dirac; g-factor; gyrmagnetisk kvot ;

    Abstract : In this project a theoretical study of the so called gyromagnetic ratio was done by investigating classical mechanics, Dirac theory and string theory. The gyromagnetic ratio is a constant term appearing in the coupling between angular momentum and magnetic moment for a particle. READ MORE

  4. 3. Equivalence of the sine-Gordon Model and the Massive Thirring Model: Derivations and Application

    University essay from Lunds universitet/Teoretisk partikelfysik - Geonomgår omorganisation

    Author : Erik Linnér; [2017]
    Keywords : sine-Gordon model; Thirring model; Schwinger model; Bosonization; Physics and Astronomy;

    Abstract : The equivalence of the sine-Gordon model and the massive Thirring model, (1+1) dimensional theories of a single scalar field respectively a single Dirac field, is derived by two alternative approaches. The equivalence is derived by a comparison of the perturbation expansions of the correlation functions of the theories around the corresponding massless theories. READ MORE

  5. 4. Discretization of the Dirac delta function for application in option pricing

    University essay from Uppsala universitet/Avdelningen för beräkningsvetenskap

    Author : Håkan Öhrn; Adam Lindell; [2016]
    Keywords : ;

    Abstract : This paper compares two different approximations of the Dirac deltafunction used in a Fokker-Planck equation. Both methods deal with the singularity problem in the initial condition. The Dirac delta approximation, constructed in MATLAB with a method derived by Tornberg and Engquist, was compared to an already given method Aït-Sahalia. READ MORE

  6. 5. The Dirac Equation in the Low Energy Limit

    University essay from Umeå universitet/Institutionen för fysik

    Author : Björn Linder; [2016]
    Keywords : ;

    Abstract : The purpose of this work is to give an introduction to relativistic quantum mechanics for the electron. First a review of the Dirac equation and its application to a free electron and an electron in an electromagnetic field will be given. In particular the hydrogen atom is studied. READ MORE