Infinitely stably extendable vector bundles on projective spaces

Iustin Coanda

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arXiv · 0907.4040

Infinitely stably extendable vector bundles on projective spaces

Iustin Coanda

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Abstract

According to Horrocks (1966), a vector bundle E on the projective n-space extends stably to the projective N-space, N>n, if there exists a vector bundle on the larger space whose restriction to the smaller one is isomorphic to E plus a direct sum of line bundles. We show that E extends stably to the projective N-space for every N>n if and only if E is the cohomology of a free monad (with three terms). The proof uses the method of Coanda and Trautmann (2006). Combining this result with a theorem of Mohan Kumar, Peterson and Rao (2003), we get a new effective version of the Babylonian tower theorem for vector bundles on projective spaces.

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Iustin Coanda. 2009-07-23. Infinitely stably extendable vector bundles on projective spaces. https://arxiv.org/abs/0907.4040

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