68 citations · 765 across the 90 of their papers we have counts for
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Remarks on a solvable cosmological model
Ion I. Cotaescu, Dumitru N. Vulcanov
We present an exact analytical solution of the Einstein equations with cosmological constant in a spatially flat Robertson-Walker metric. This is interpreted as an isotropic Lemait…
Polarized Dirac fermions in de Sitter spacetime
Ion I. Cotaescu
The tetrad gauge invariant theory of the free Dirac field in two special moving charts of the de Sitter spacetime is investigated pointing out the operators that commute with the D…
Hierarchy of Dirac, Pauli and Klein-Gordon conserved operators in Taub-NUT background
Ion I. Cotăescu, Mihai Visinescu
The algebra of conserved observables of the SO(4,1) gauge-invariant theory of the Dirac fermions in the external field of the Kaluza-Klein monopole is investigated. It is shown tha…
Non-existence of f-symbols in generalized Taub-NUT spacetimes
Ion I. Cotăescu, Mihai Visinescu
In a previous article it was proved that the extensions of the Taub-NUT geometry do not admit Killing-Yano tensors, even if they possess St\" {a}ckel-Killing tensors. Here the anal…
Dynamical algebra and Dirac quantum modes in Taub-NUT background
Ion I. Cotăescu, Mihai Visinescu
The SO(4,1) gauge-invariant theory of the Dirac fermions in the external field of the Kaluza-Klein monopole is investigated. It is shown that the discrete quantum modes are governe…
Runge-Lenz operator for Dirac field in Taub-NUT background
Ion I. Cotăescu, Mihai Visinescu
Fermions in D=4 self-dual Euclidean Taub-NUT space are investigated. Dirac-type operators involving Killing-Yano tensors of the Taub-NUT geometry are explicitly given showing that…