Equivariant spectral triple for the quantum group Uq(2) for complex deformation parameters
Source
Journal of Geometry and Physics
ISSN
03930440
Date Issued
2023-03-01
Author(s)
Guin, Satyajit
Abstract
Let q=|q|e<sup>iπθ</sup> be a nonzero complex number such that |q|≠1 and consider the compact quantum group U<inf>q</inf>(2). For θ∉Q∖{0,1}, we obtain the K-theory of the underlying C<sup>⁎</sup>-algebra C(U<inf>q</inf>(2)). We construct a spectral triple on U<inf>q</inf>(2) which is equivariant under its own comultiplication action. The spectral triple obtained here is even, 4<sup>+</sup>-summable, non-degenerate, and the Dirac operator acts on two copies of the L<sup>2</sup>-space of U<inf>q</inf>(2). The K-homology class of the associated Fredholm module is shown to be nontrivial.
Subjects
Compact quantum group | Equivariance | Quantum unitary group | Spectral triple
