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Lorentz-covariant deformed algebra with minimal length and application to the 1+1-dimensional Dirac oscillator

C. Quesne·V. M. Tkachuk
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Abstract

The $D$-dimensional $(\beta, \beta')$-two-parameter deformed algebra introduced by Kempf is generalized to a Lorentz-covariant algebra describing a ($D+1$)-dimensional quantized space-time. In the D=3 and $\beta=0$ case, the latter reproduces Snyder algebra. The deformed Poincar\'e transformations leaving the algebra invariant are identified. It is shown that there exists a nonzero minimal uncertainty in position (minimal length). The Dirac oscillator in a 1+1-dimensional space-time described by such an algebra is studied in the case where $\beta'=0$. Extending supersymmetric quantum mechanical and shape-invariance methods to energy-dependent Hamiltonians provides exact bound-state energies and wavefunctions. Physically acceptable states exist for $\beta < 1/(m^2 c^2)$. A new interesting outcome is that, in contrast with the conventional Dirac oscillator, the energy spectrum is bounded.

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C. Quesne, V. M. Tkachuk. 2006-04-17. Lorentz-covariant deformed algebra with minimal length and application to the 1+1-dimensional Dirac oscillator. https://doi.org/10.1088/0305-4470/39/34/021

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