A remarkable dynamical symmetry of the Landau problem

Abstract

We show that the dynamical group of an electron in a constant magnetic field is the group of symplectomorphisms $Sp(4,\mathbb{R})$. It is generated by the spinorial realization of the conformal algebra $\mathfrak{so}(2,3)$ considered in Dirac's seminal paper "A Remarkable Representation of the 3 + 2 de Sitter Group". The symplectic group $Sp(4,\mathbb{R})$ is the double covering of the conformal group $SO(2,3)$ of 2+1 dimensional Minkowski spacetime which is in turn the dynamical group of a hydrogen atom in 2 space dimensions. The Newton-Hooke duality between the 2D hydrogen atom and the Landau problem is explained via the Tits-Kantor-Koecher construction of the conformal symmetries of the Jordan algebra of real symmetric $2\times 2$ matrices. The connection between the Landau problem and the 3D hydrogen atom is elucidated by the reduction of a Dirac spinor to a Majorana one in the Kustaanheimo-Stiefel spinorial regularization.

17 pages

References in corpus (8)

• Schr"odinger invariance and space-time symmetries
• The two-dimensional hydrogen atom revisited
• Generalized Conformal and Superconformal Group Actions and Jordan Algebras
• Exceptional quantum geometry and particle physics
• Euclidean Jordan Algebras, Hidden Actions, and $J$-Kepler Problems
• Dyon-Oscillator Duality
• Poincaré Symmetry from Heisenberg's Uncertainty Relations
• Duality Between Hydrogen Atom and Oscillator Systems via Hidden SO(d,2) Symmetry and 2T-physics