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arXiv · 1903.07650

Zitterbewegung in Noncommutative Geometry

Mehran Zahiri Abyaneh·Mehrdad Farhoudi
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Abstract

We have considered the effects of space and momentum noncommutativity separately on the zitterbewegung (ZBW) phenomenon. In the space noncommutativity scenario, it has been expressed that, due to the conservation of momentum, the Fourier decomposition of the expectation value of position does~not change. However, the noncommutative (NC) space corrections to the magnetic dipole moment of electron, that was traditionally perceived to come into play only in the first-order of perturbation theory, appear in the leading-order calculations with the similar structure and numerically the same order, but with an opposite sign. This result may explain why for large lumps of masses, the Zeeman-effect due to the noncommutativity remains undetectable. Moreover, we have shown that the $x$- and $y$-components of the electron magnetic dipole moment, contrary to the commutative (usual) version, are non-zero and with the same structure as the $z$-component. In the momentum noncommutativity case, we have indicated that, due to the relevant external uniform magnetic field, the energy-spectrum and also the solutions of the Dirac equation are changed in $3+1$ dimensions. In addition, our analysis shows that in $2+1$ dimensions, the resulted NC field makes electrons in the zero Landau-level rotate not only via a cyclotron motion, but also through the ZBW motion with a frequency proportional to the field, which doubles the amplitude of the rotation. In fact, this is a hallmark of the ZBW in graphene that provides a promising way to be tested experimentally.

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Mehran Zahiri Abyaneh, Mehrdad Farhoudi. 2019-03-18. Zitterbewegung in Noncommutative Geometry. https://doi.org/10.1142/s0217751x19500453

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