Equivariant isomorphism of Quantum Lens Spaces of low dimension

Abstract

The quantum lens spaces form a natural and well-studied class of noncommutative spaces which has been partially classified using algebraic invariants drawing on the developed classification theory of graph $C^*$-algebras. We introduce the problem of deciding when two quantum lens spaces are equivariantly isomorphic, and solve it in certain basic cases. The results can be formulated directly in terms of the parameters defining the quantum lens spaces, and here occasionally take on a rather complicated from which convinces us that there is a deep underlying explanation for our findings. We complement the fully established partial results with computer experiments that may indicate the way forward.