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Dec 8, 2014 at 8:54 vote accept AlexE
Dec 8, 2014 at 8:54 answer added AlexE timeline score: 0
Dec 3, 2014 at 8:27 comment added AlexE Yes, I assume that $P$ is essentially self-adjoint so that it indeed defines an element of $K_1(M)$. I also assume the manifold to be compact (and without boundary). Applying the homological Chern character (constructed by using Connes' cyclic cohomology), we get an element of $H_\ast(M)$ and I want to identify the Poincare dual of it. If $P$ is graded the Poincare dual is, up to some universal constants, $ind(P)$ which is computed / constructed using the clutching construction. This is a generalization of Atiyah-Singer. But what is this Poincare dual now in the ungraded case?
Dec 2, 2014 at 21:45 comment added Johannes Ebert Typically, you would replace the operator $P$ by $P \oplus P^{\ast}: E \oplus F \to E \oplus F$. This is graded, and the index (in the graded sense) is the usual index. An ungraded operator has an index in $K^1$, but only if it is self-adjoint.
Dec 2, 2014 at 16:25 comment added Paul Siegel There are a number of index theorems for operators whose K-homology classes live in the odd degree groups for whatever reason, but typically you need the operator to have some extra structure. Do you have a specific operator in mind?
Dec 2, 2014 at 16:17 history asked AlexE CC BY-SA 3.0