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Related papers: A semiclassical approach to the Dirac equation

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Trajectories are a central concept in our understanding of classical phenomena and also in rationalizing quantum mechanical effects. In this work we provide a way to determine semiclassical paths, approximations to quantum averages in phase…

Quantum Physics · Physics 2015-06-15 Rafael Liberalquino , Fernando Parisio

Periodic orbit quantization requires an analytic continuation of non-convergent semiclassical trace formulae. We propose two different methods for semiclassical quantization. The first method is based upon the harmonic inversion of…

Chaotic Dynamics · Physics 2007-05-23 J. Main , G. Wunner

We consider the model of Dirac fermions coupled to gravity as proposed in \cite{VolovikBH}, in which superluminal velocities of particles are admitted. In this model an extra term is added to the conventional Hamiltonian that originates…

General Relativity and Quantum Cosmology · Physics 2019-06-28 M. Lewkowicz , M. A. Zubkov

We develop a semiclassical theory for spin-dependent quantum transport in ballistic quantum dots. The theory is based on the semiclassical Landauer formula, that we generalize to include spin-orbit and Zeeman interaction. Within this…

Mesoscale and Nanoscale Physics · Physics 2015-06-25 Oleg Zaitsev , Diego Frustaglia , Klaus Richter

Consistent dynamics which couples classical and quantum degrees of freedom exists, provided it is stochastic. This dynamics is linear in the hybrid state, completely positive and trace preserving. One application of this is to study the…

Quantum Physics · Physics 2023-01-04 Jonathan Oppenheim , Carlo Sparaciari , Barbara Šoda , Zachary Weller-Davies

The Dirac method is used to analyze the classical and quantum dynamics of a particle constrained on a circle. The method of Lagrange multipliers is scrutinized, in particular in relation to the quantization procedure. Ordering problems are…

Quantum Physics · Physics 2015-06-26 Antonello Scardicchio

We summarize semiclassical modeling methods, including drift-diffusion, kinetic transport equation and Monte Carlo simulation approaches, utilized in studies of spin dynamics and transport in semiconductor structures. As a review of the…

Mesoscale and Nanoscale Physics · Physics 2010-10-12 S. Saikin , Yu. V. Pershin , V. Privman

The long-standing problem of time in canonical quantum gravity is the source of several conceptual and technical issues. Here, recent mathematical results are used to provide a consistent algebraic formulation of dynamical symplectic…

General Relativity and Quantum Cosmology · Physics 2023-01-04 Martin Bojowald , Artur Tsobanjan

The kinetic equation used for the description of Dirac systems does not fully take into account two features that play an important role in the vicinity of the Dirac point: (i) the spin degree of freedom, in particular if the spin-flip…

Mesoscale and Nanoscale Physics · Physics 2020-11-19 Oleksiy Kashuba , Björn Trauzettel , Laurens W. Molenkamp

Conventional transport theory focuses on either the diffusive or ballistic regimes and neglects the crossover region between the two. In the presence of spin-orbit coupling, the transport equations are known only in the diffusive regime,…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 B. Andrei Bernevig , Jiangping Hu

We obtain by invariance arguments the relativistic and non-relativistic invariant dynamical equations of a classical model of a spinning electron. We apply the formalism to a particular classical model which satisfies Dirac's equation when…

Classical Physics · Physics 2008-11-26 Martin Rivas

We show that the principal part of the Dirac Hamiltonian in 3+1 dimensions emerges in a semi-classical approximation from a construction which encodes the kinematics of quantum gravity. The construction is a spectral triple over a…

High Energy Physics - Theory · Physics 2011-03-18 Johannes Aastrup , Jesper M. Grimstrup , Mario Paschke

Using the position as an independent variable, and time as the dependent variable, we derive the function ${\cal P}^{(\pm)}$, which generates the space evolution under the potential ${\cal V}(q)$ and Hamiltonian ${\cal H}$. Canonically…

Quantum Physics · Physics 2023-07-31 Marcus W Beims , Arlans JS Lara

We consider a classical Dirac field in flat Minkowski spacetime. We perform a Gordon decomposition of its canonical energy-momentum and spin currents, respectively. Thereby we find for each of these currents a convective and a polarization…

General Relativity and Quantum Cosmology · Physics 2016-08-15 F. W. Hehl , A. Macías , E. W. Mielke , Yu. N. Obukhov

The motion of a magnetic spin particle in electromagnetic fields is considered on the basis of general principles of the classical relativistic theory. Alternative approaches in derivation of the equations of charge motion and spin…

Quantum Physics · Physics 2017-08-23 V. A. Bordovitsyn , A. N. Myagkii

A generalization of the Lagrangian introduced earlier in [2011 {\it J. Phys. G} ${\bf 37}$ 105001] for a classical color spinning particle interacting with background non-Abelian gauge and fermion fields for purpose of considering a change…

High Energy Physics - Theory · Physics 2011-12-12 Yuri A. Markov , Margarita A. Markova , Alexey A. Shishmarev , Alexander N. Vall

We derive the analogues of the Dirac and Pauli equations from a spatially fourth-order Klein--Gordon equation with a universal length scale. Starting from a singularly perturbed variant of Maxwell's equations, we deduce a 32-dimensional…

Quantum Physics · Physics 2025-07-22 Tiemo Pedergnana , Florian Kogelbauer

We apply the semi-classical limit of the generalized $SO(3)$ map for representation of variable-spin systems in a four-dimensional symplectic manifold and approximate their evolution terms of effective classical dynamics on $T^{\ast…

Thermal escape out of a metastable well is considered in the weak friction regime, where the bottleneck for decay is energy diffusion, and at lower temperatures, where quantum tunneling becomes relevant. Within a systematic semiclassical…

Statistical Mechanics · Physics 2015-05-13 Alvise Verso , Joachim Ankerhold

We derive the semi-classical gravitational dynamics from thermodynamics of local stretched light cones in 2-dimensional dilaton gravity, explicitly treating the backreaction of quantum matter through the conformal anomaly's effect on the…

High Energy Physics - Theory · Physics 2026-05-07 Ana Alonso-Serrano , Marek Liška , Michał Piotrak