κ-Minkowski spacetime through exotic “oscillator”

Abstract

We have proposed a generally covariant non-relativistic particle model that can represent the κ-Minkowski noncommutative spacetime. The idea is similar in spirit to the noncommutative particle coordinates in the lowest Landau level. Physically our model yields a novel type of dynamical system (termed here as exotic “oscillator”), that obeys a harmonic oscillator like equation of motion with a frequency that is proportional to the square root of energy. On the other hand, the phase diagram does not reveal a closed structure since there is a singularity in the momentum even though energy remains finite. The generally covariant form is related to a generalization of the Snyder algebra in a specific gauge and yields the κ-Minkowski spacetime after a redefinition of the variables. Symmetry considerations are also briefly discussed in the Hamiltonian formulation. Regarding continuous symmetry, the angular momentum acts properly as the generator of rotation. Interestingly, both the discrete symmetries, parity and time reversal, remain intact in the κ-Minkowski spacetime.