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Suppose we have an evaporating black hole and a nonabelian Yang-Mills theory with a $\theta$ topological term. This counts the total number of instantons minus antiinstantons. Consider the total number of instantons minus antiinstantons inside the black hole, i.e. between the event horizon and the singularity. This is equal to the difference between Chern-Simons integral between the singularity and event horizon. According to black hole complementarity, we replace the interior with a stretched horizon. Do we have to add an effective Chern-Simons term to the stretched horizon action? If so, is this equivalent to saying the CS integral over the singularity has to be zero? Otherwise, we get decoherence by CS singularity value, converting pure states to mixed states?

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ok, no downvote, maybe this is sincere. The singularity isn't space--- r is time inside the BH. Instanton count is in imaginary time. – Ron Maimon Jul 30 '12 at 15:39

Instantons are in imaginary time, not real time. The instanton number doesn't make sense in the interior of a black hole, you can define it on the exterior when you continue the exterior solution.

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No, the Cherns-Simons integral will always be a positive value, although small, since it has been proven that antiinstantons are less likely to escape the event horizon. This is how the universe we exist in is primarily made of matter as the anti-matter components get trapped in black holes.

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-1: this is nonsense. Instantons aren't matter, they don't even exist in real space (at least not the same way they are in imaginary time), they are tunneling configurations. – Ron Maimon Jul 30 '12 at 15:37

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