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arXiv · 1908.06861

The Euler Characteristic Of A Transitive Lie Algebroid

James Waldron
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Abstract

We apply the Atiyah-Singer index theorem and tensor products of elliptic complexes to the cohomology of transitive Lie algebroids. We prove that the Euler characteristic of a representation of a transitive Lie algebroid $A$ over a compact manifold $M$ vanishes unless $A=TM$, and prove a general K\"{u}nneth formula. As applications we give a short proof of a vanishing result for the Euler characteristic of a principal bundle calculated using invariant differential forms, and show that the cohomology of certain Lie algebroids are exterior algebras. The latter result can be seen as a generalization of Hopf's theorem regarding the cohomology of compact Lie groups.

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James Waldron. 2019-08-19. The Euler Characteristic Of A Transitive Lie Algebroid. https://arxiv.org/abs/1908.06861

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