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Related papers: Flavoured quantum Boltzmann equations from cQPA

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We present a simplified and generalized derivation of the flavour-coherent propagators and Feynman rules for the fermionic kinetic theory based on coherent quasiparticle approximation (cQPA). The new formulation immediately reveals the…

High Energy Physics - Phenomenology · Physics 2015-05-30 Matti Herranen , Kimmo Kainulainen , Pyry Matti Rahkila

We reformulate and extend our recently introduced quantum kinetic theory for interacting fermion and scalar fields. Our formalism is based on the coherent quasiparticle approximation (cQPA) where nonlocal coherence information is encoded in…

High Energy Physics - Phenomenology · Physics 2011-01-26 Matti Herranen , Kimmo Kainulainen , Pyry Matti Rahkila

We show that the dynamical Wigner functions for noninteracting fermions and bosons can have complex singularity structures with a number of new solutions accompanying the usual mass-shell dispersion relations. These new shell solutions are…

High Energy Physics - Phenomenology · Physics 2014-11-20 Matti Herranen , Kimmo Kainulainen , Pyry M. Rahkila

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…

High Energy Physics - Theory · Physics 2020-01-15 Henri Jukkala , Kimmo Kainulainen , Olli Koskivaara

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…

High Energy Physics - Phenomenology · Physics 2021-10-01 Henri Jukkala , Kimmo Kainulainen , Pyry M. Rahkila

In this thesis we develop a novel approximation scheme (eQPA), where the effects of nonlocal coherence are included in the kinetic approach to nonequilibrium quantum dynamics. The key element in our formalism is the finding of new singular…

High Energy Physics - Phenomenology · Physics 2009-06-18 Matti Herranen

We derive quantum kinetic equations for mixing neutrinos including consistent forward scattering terms and collision integrals for coherent neutrino states. In practice, we reduce the general Kadanoff--Baym equations in a few clearly…

High Energy Physics - Phenomenology · Physics 2023-09-06 Kimmo Kainulainen , Harri Parkkinen

We derive field-theoretic local quantum transport equations which can describe quantum coherence. Our methods are based on Kadanoff--Baym equations derived in the Schwinger--Keldysh closed time path formalism of non-equilibrium quantum…

High Energy Physics - Phenomenology · Physics 2022-11-23 Henri Jukkala

We derive from first principles, using non-equilibrium field theory, the quantum Boltzmann equations that describe the dynamics of flavor oscillations, collisions, and a time-dependent mass matrix in the early universe. Working to leading…

High Energy Physics - Phenomenology · Physics 2010-05-25 Vincenzo Cirigliano , Christopher Lee , Michael J. Ramsey-Musolf , Sean Tulin

We derive transport equations for fermions and bosons in spatially or temporally varying backgrounds with special symmetries, by use of the Schwinger-Keldysh formalism. In a noninteracting theory the coherence information is shown to be…

High Energy Physics - Phenomenology · Physics 2014-11-18 Matti Herranen , Kimmo Kainulainen , Pyry M. Rahkila

We study quantum phase coherence and weak localization (WL) in disordered metals with restricted back-scattering and phenomenologically formulate a large class of unconventional transport mechanisms as modified diffusion processes not…

Disordered Systems and Neural Networks · Physics 2010-08-06 Shimul Akhanjee

We consider the conductivity tensor for composite fermions in a close to half-filled Landau band in the temperature regime where the scattering off the potential and the trapped gauge field of random impurities dominates. The Boltzmann…

Mesoscale and Nanoscale Physics · Physics 2009-10-30 A. D. Mirlin , P. Woelfle

Flavour effects play an important role in the statistical evolution of particle number densities in several particle physics phenomena. We present a fully flavour-covariant formalism for transport phenomena, in order to consistently capture…

High Energy Physics - Phenomenology · Physics 2015-08-27 P. S. Bhupal Dev , Peter Millington , Apostolos Pilaftsis , Daniele Teresi

The semi-classical Bloch-Boltzmann theory is at the heart of our understanding of conduction in solids, ranging from metals to semi-conductors. Physical systems that are beyond the range of applicability of this theory are thus of…

Materials Science · Physics 2007-12-18 Didier Mayou , Guy Trambly De Laissardière

With a view of applications to the simulations of supernova explosion and proto neutron star cooling, we derive the Boltzmann equations for the neutrino transport with the flavor mixing based on the real time formalism of the nonequilibrium…

Astrophysics · Physics 2009-10-31 Shoichi Yamada

Traditional theories of electron transport in crystals are based on the Boltzmann equation and do not capture physics arising from quantum coherence. We introduce a transport formalism based on ''orbital Wigner functions'', which accurately…

We derive quantum kinetic equations for fermions in a homogeneous time-dependent background in presence of decohering collisions, by use of the Schwinger-Keldysh CTP-formalism. The quantum coherence (between particles and antiparticles) is…

High Energy Physics - Phenomenology · Physics 2009-03-24 Matti Herranen , Kimmo Kainulainen , Pyry Matti Rahkila

We discuss some aspects of a recently proposed semi-classical transport theory for QCD plasmas based on coloured point particles. This includes the derivation of effective transport equations for mean fields and fluctuations which relies on…

High Energy Physics - Phenomenology · Physics 2017-08-23 Daniel F. Litim

We derive quantum Boltzmann equations from Schwinger-Dyson equations in gradient expansion for a weakly coupled scalar field theory with a spatially varying mass. We find that at higher order in gradients a full description of the system…

High Energy Physics - Phenomenology · Physics 2009-10-31 Michael Joyce , Kimmo Kainulainen , Tomislav Prokopec

The leading corrections to Fermi liquid theory for non-equilibrium quasiparticle transport near a Cooper instability arise from the virtual emission and absorption of incipient Cooper pairs. We formulate the corrections to the…

Superconductivity · Physics 2021-10-28 Wei-Ting Lin , J. A. Sauls
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