The Fredholm index for operators of tensor product type
arXiv:1812.05427
Abstract
We consider bisingular pseudodifferential operators which are pseudodifferential operators of tensor product type. These operators are defined on the product manifold , for closed manifolds and . We prove a topological index theorem of product type. In addition, we show that the Fredholm index of elliptic bisingular operators equals the topological index, whenever the operator takes the form of an external tensor product of pseudodifferential operators, up to equivalence. To this end we construct a suitable double deformation groupoid and a Poincaré duality type homomorphism.
Revised version. To appear in JOT