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arXiv · 1512.08534

Lower bounds on projective levels of complexes

Hannah Altmann·Eloísa Grifo·Jonathan Montaño·William Sanders·Thanh Vu
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Abstract

For an associative ring $R$, the projective level of a complex $F$ is the smallest number of mapping cones needed to build $F$ from projective $R$-modules. We establish lower bounds for the projective level of $F$ in terms of the vanishing of homology of $F$. We then use these bounds to derive a new version of The New Intersection Theorem for level when $R$ is a commutative Noetherian local ring.

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Hannah Altmann, Eloísa Grifo, Jonathan Montaño, William Sanders, Thanh Vu. 2017-08-16. Lower bounds on projective levels of complexes. https://doi.org/10.1016/j.jalgebra.2017.08.013

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