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arXiv · 1409.5325

Kahler Potential and Ambiguities in 4d N=2 SCFTs

Jaume Gomis·Nafiz Ishtiaque
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Abstract

The partition function of four-dimensional N=2 superconformal field theories on S^4 computes the exact Kahler potential on the space of exactly marginal couplings [1]. We present a new elementary proof of this result using supersymmetry Ward identities. The partition function is a section rather than a function, and is subject to ambiguities coming from Kahler transformations acting on the Kahler potential. This ambiguity is realized by a local supergravity counterterm in the underlying SCFT. We provide an explicit construction of the Kahler ambiguity counterterm in the four dimensional N=2 off-shell supergravity theory that admits S^4 as a supersymmetric background.

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Jaume Gomis, Nafiz Ishtiaque. 2016-02-09. Kahler Potential and Ambiguities in 4d N=2 SCFTs. https://doi.org/10.1007/jhep04(2015)169

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