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arXiv · 1504.00961

Existence of Dirac Eigenvalues of higher Multiplicity

Nikolai Nowaczyk
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Abstract

In this article, we prove that on any compact spin manifold of dimension m congruent 0,6,7 mod 8, there exists a metric, for which the associated Dirac operator has at least one eigenvalue of multiplicity at least two. We prove this by catching the desired metric in a subspace of Riemannian metrics with a loop that is not homotopically trivial. We show how this can be done on the sphere with a loop of metrics induced by a family of rotations. Finally, we transport this loop to an arbitrary manifold (of suitable dimension) by extending some known results about surgery theory on spin manifolds.

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Nikolai Nowaczyk. 2015-04-04. Existence of Dirac Eigenvalues of higher Multiplicity. https://doi.org/10.1007/s00209-016-1657-2

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