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arXiv · 1502.05252

Eigenvalue Estimates of the ${\rm spin}^c$ Dirac Operator and Harmonic Forms on K\"ahler-Einstein Manifolds

Roger Nakad·Mihaela Pilca
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Abstract

We establish a lower bound for the eigenvalues of the Dirac operator defined on a compact K\"ahler-Einstein manifold of positive scalar curvature and endowed with particular ${\rm spin}^c$ structures. The limiting case is characterized by the existence of K\"ahlerian Killing ${\rm spin}^c$ spinors in a certain subbundle of the spinor bundle. Moreover, we show that the Clifford multiplication between an effective harmonic form and a K\"ahlerian Killing ${\rm spin}^c$ spinor field vanishes. This extends to the ${\rm spin}^c$ case the result of A. Moroianu stating that, on a compact K\"ahler-Einstein manifold of complex dimension $4\ell+3$ carrying a complex contact structure, the Clifford multiplication between an effective harmonic form and a K\"ahlerian Killing spinor is zero.

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Roger Nakad, Mihaela Pilca. 2015-02-18. Eigenvalue Estimates of the ${\rm spin}^c$ Dirac Operator and Harmonic Forms on K\"ahler-Einstein Manifolds. https://doi.org/10.3842/sigma.2015.054

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