Lower Bounds for the Eigenvalues of the Dirac Operator on Spinc Manifolds Roger NAKAD May 13, 2010 Institut Elie Cartan, Universite Henri Poincare, Nancy I, B.P 239 54506 Vandœuvre-Les-Nancy Cedex, France. Abstract In this paper, we extend the Hijazi inequality, involving the Energy-Momentum tensor, for the eigenvalues of the Dirac operator on Spinc manifolds without boundary. The limiting case is then studied and an example is given. Key words: Spinc structures, Dirac operator, eigenvalues, Energy-Momentum tensor, perturbed Yamabe operator, conformal geometry. 1 Introduction On a compact Riemannian spin manifold (Mn, g) of dimension n > 2, Th. Friedrich [6] showed that any eigenvalue ? of the Dirac operator satisfies ?2 > ?21 := n 4(n? 1) inf M Sg, (1) where Sg denotes the scalar curvature of M . The limiting case of (1) is characterized by the existence of a special spinor called real Killing spinor. This is a section ? of the spinor bundle satisfying for every X ? ?(TM), ?X? = ? ?1 n X · ?, 1
- any eigenvalue
- then any
- line bundle has
- killing spinor
- spinc manifold
- ?y ?
- energy- momentum tensor
- compact riemannian
- q? defined