0000000001071380

AUTHOR

Henri Jukkala

Flavour mixing transport theory and resonant leptogenesis

We derive non-equilibrium quantum transport equations for flavour-mixing fermions. We develop the formalism mostly in the context of resonant leptogenesis with two mixing Majorana fermions and one lepton flavour, but our master equations are valid more generally in homogeneous and isotropic systems. We give a hierarchy of quantum kinetic equations, valid at different approximations, that can accommodate helicity and arbitrary mass differences. In the mass-degenerate limit the equations take the familiar form of density matrix equations. We also derive the semiclassical Boltzmann limit of our equations, including the CP-violating source, whose regulator corresponds to the flavour coherence d…

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Quantum transport and the phase space structure of the Wightman functions

We study the phase space structure of exact quantum Wightman functions in spatially homogeneous, temporally varying systems. In addition to the usual mass shells, the Wightman functions display additional coherence shells around zero frequency $k_0=0$, which carry the information of the local quantum coherence of particle-antiparticle pairs. We find also other structures, which encode non-local correlations in time, and discuss their role and decoherence. We give a simple derivation of the cQPA formalism, a set of quantum transport equations, that can be used to study interacting systems including the local quantum coherence. We compute quantum currents created by a temporal change in a par…

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Neutriinojen ja kvarkkien sekoitusmatriisien välinen yhteys

In this thesis relations between neutrino mixing matrix and quark mixing matrix are studied. The focus of the analysis is on two simple cases. In the first case it is assumed that the left matrix that diagonalizes the mass matrix of charged leptons and the corresponding matrix of down quarks are equal. In the second case it is likewise assumed that the corresponding diagonalizing matrices of neutrinos and up quarks are equal. First, theoretical concepts related to the mixing of quarks and especially to the mixing of neutrinos are presented. These are e.g. fermion mass generation in the Standard Model, Majorana masses of neutrinos and the so-called seesaw mechanism. Regarding experiments, ne…

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LeptoGen-koodi

LeptoGen is a software package for numerically solving (resonant) leptogenesis equations including full flavour coherence information for the Majorana neutrinos. The package is written in Wolfram Language and can be run in the Mathematica front end. (Tested in Mathematica 12.0.) For usage license, see the attachment.

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