Sökning: "Bethe ansatz"

Hittade 4 uppsatser innehållade orden Bethe ansatz.

  1. 1. Integrability and Thermodynamics of the Gross-Neveu Model

    Master-uppsats, KTH/Fysik

    Författare :Valdemar Melin; [2023]
    Nyckelord :Mathematical Physics; Quantum Field Theory; Bethe Ansatz; Gross-Neveu Model; Matematisk fysik; kvantfältteori; Bethe-ansatsen; Gross-Neveu-modellen;

    Sammanfattning : The Gross-Neveu model is a quantum field theory of interacting N-flavor fermions in 1+1dimensions, with interaction term $(\bar{\psi}_f\psi_f )^2$. This model is studied using the property offactorized scattering. LÄS MER

  3. 2. Crosscap States in Integrable Spin Chains

    Master-uppsats, KTH/Fysik

    Författare :Christopher Ekman; [2022]
    Nyckelord :Theoretical Physics; Mathematical Physics; Integrability; Integrable Systems; Spin chains; Heisenberg model; Integrable Boundary States; Crosscap states; Teoretisk fysik; Matematisk fysik; Integrabilitet; Integrabla system; Spinnkedjor; Heisenbergmodellen; Integrabla gränstillstånd; Crosscaptillstånd;

    Sammanfattning : We consider integrable boundary states in the Heisenberg model. We begin by reviewing the algebraic Bethe Ansatz as well as integrable boundary states in spin chains. Then a new class of integrable states that was introduced last year by Caetano and Komatsu is described and expanded. We call these states the crosscap states. LÄS MER

  4. 3. Many-body-based DFT treatment of fermions in optical lattices

    Kandidat-uppsats, Lunds universitet/Fysiska institutionen; Lunds universitet/Matematisk fysik

    Författare :Jérémie Westergren; [2017]
    Nyckelord :DFT; density functional theory; MBA; many-body approximations; Hubbard model; Ultra cold atoms; cold atoms; optical lattice; Physics and Astronomy;

    Sammanfattning : With recent advances in the field of ultra cold atoms one can, by trapping atoms at low temperatures by laser beams, simulate systems which can be adequately described by single-band lattice Hamiltonians. Also, due to the high parameter tunability of the experimental setups, lattice disorder can be introduced in a con- trolled fashion in these systems. LÄS MER

  5. 4. Analysis of the Many-Body Problem in One Dimension with Repulsive Delta-Function Interaction

    Kandidat-uppsats, Uppsala universitet/Teoretisk fysik

    Författare :Martin Albertsson; [2014]
    Nyckelord :Many-body problem; Bethe ansatz; delta-function interaction; Bethe-Yang ansatz; Gaudin-Yang model; Lieb-Liniger model;

    Sammanfattning : The repulsive delta-function interaction model in one dimension is reviewed for spinless particles and for spin-1/2 fermions. The problem of solving the differential equation related to the Schrödinger equation is reduced by the Bethe ansatz to a system of algebraic equations. LÄS MER