Taylor and Lyubeznik resolutions via Grobner bases

Taylor presented an explicit resolution for arbitrary monomial ideals. Later, Lyubeznik found that a subcomplex already defines a resolution. We show that the Taylor resolution may be obtained by repeated application of the Schreyer Theorem from the theory of Grobner bases, whereas the Lyubeznik resolution is a consequence of Buchberger's chain criterion. Finally, we relate Froberg's contracting homotopy for the Taylor complex to normal forms with respect to our Grobner bases and use it to derive a splitting homotopy that leads to the Lyubeznik complex. (C) 2002 Elsevier Science Ltd. All rights reserved.