Abstract
Extending a result of He to the non-integrable case of K-contact manifolds, it is shown that the transverse Hermitian scalar curvature may be interpreted as a moment map for the strict contactomorphism group. As a consequence, we may generalize the Sasaki–Futaki invariant to K-contact geometry and establish a number of elementary properties. Moreover, we prove that in dimension 5 certain deformation-theoretic results can be established also under weaker integrability conditions by exploiting the relationship between J-anti-invariant and self-dual 2-forms.
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Acknowledgments
The first named author is very grateful to Christina Tønnesen-Friedman and Charles Boyer for useful discussions. The first named author is also grateful to Vestislav Apostolov for helpful comments. Both authors are thankful to Joel Fine and Weiyong He for several useful discussions.
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Lejmi, M., Upmeier, M. Extremal K-contact metrics. Math. Z. 281, 673–687 (2015). https://doi.org/10.1007/s00209-015-1503-y
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DOI: https://doi.org/10.1007/s00209-015-1503-y