|
We establish a splitting formula for the spectral flow of the odd
signature operator on a closed 3–manifold M coupled to a path of
SU(2) connections, provided M = S∪X, where S is the solid
torus. It describes the spectral flow on M in terms of the spectral flow
on S, the spectral flow on X (with certain Atiyah–Patodi–Singer
boundary conditions), and two correction terms which depend only on
the endpoints.
Our result improves on other splitting theorems by removing assumptions
on the non-resonance level of the odd signature operator or the dimension
of the kernel of the tangential operator, and allows progress towards
a conjecture by Lisa Jeffrey in her work on Witten's 3–manifold
invariants in the context of the asymptotic expansion
conjecture.
|