A Vanishing Result for Teleman’s Casson-type Instanton Invariant
نویسنده
چکیده
Recently Andrei Teleman considered instanton moduli spaces over negative definite four-manifolds X with b2(X) ≥ 1. If b2(X) is divisble by four and b1(X) = 1 a gauge-theoretic invariant can be defined; it is a count of flat connections modulo the gauge group. Our main result shows that if such a moduli space is non-empty and the manifold admits a connected sum decomposition X ∼= X1#X2 then both b2(X1) and b2(X2) are divisible by four.
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