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M. Bahadoran

Publications and source records attributed to M. Bahadoran.

2 recordsLinked to original sources

Minimal length implications on the Hartree-Fock theory

Hartree-Fock approximation suffers from two inabilities including i) the divergence of electron Fermi velocity , and ii) existence of bandwidth not confirmed experimentally. Here, we study the effects of minimal length on the ground state energy of the electron gas in the Hartree-Fock approximation. Our results indicate that considering some mathematical terms, similar to those of used for the minimal length correction to the Hamiltonian of system, can eliminate the weaknesses of Hartree-Fock approximation. These corrections, on the other hand, can be considered as relativistic corrections of electron in solids. Physically, it is obtained that electrons in metals can be employed to test the quantum gravity scenario, if the value of its parameter ($β$) lies within the range of 2 to 10, depending on the used metal. Indeed, the latter addresses an upper bound on $β$ which is comparable with previous works meaning that these types of systems may be employed in testing quantum gravity scenarios. To overcome the infinite Fermi velocity in Hartree-Fock method, the screening potential is used based on the Lindhard theory. We also found that considering the generalized Heisenberg uncertainly leads to some additional oscillating terms in the Friedel oscillations.

cond-mat.other↗

One and two spin$-1/2$ particles systems under Lorentz transformations

Lorentz transformation (LT) is used to connect two inertia frames, including the lab and moving frames, and the effect of LT on the states of one spin-1/2 particle system is studied. Moreover, we address the predictions made by Czachor's and the Pauli spin operators about the spin behavior and compare our results with the behavior of system's state under Lorentz transformation. This investigation shows that the predictions made by considering the Pauli spin operator about the spin of system are in better agreement with the system's state in comparison with that of made by considering Czachor's spin operator. In continue, we focus on two-particle pure entangled systems including two spin$-1/2$ particles which moves away from each other. Once again, the behavior of this system's states under Lorentz transformation are investigated. We also point to the behavior of Bell's inequality, as a witness for non-locality, under Lorentz transformation. Our study shows that the Bell operator made by the Pauli operator has better consistency with the behavior of spin state of system under Lorentz transformation compared with the Bell operator made by Czachor's operator. Our approach can be used to study the relation between the various spin operators and the effect of LT on system, which provides the basement to predict the outcome of a Stern-Gerlach type experiment in the relativistic situations.

quant-ph↗