The existence of equivariant pure free resolutions

David Eisenbud[1]; Gunnar Fløystad[2]; Jerzy Weyman[3]

  • [1] Dept of Mathematics Berkeley, CA 94720 (USA)
  • [2] Matematisk Institutt Johs. Brunsgt. 12 5008 Bergen (Norway)
  • [3] Northeastern University Department of Mathematics 360 Huntington Avenue Boston, MA 02115 (USA)

Annales de l’institut Fourier (2011)

  • Volume: 61, Issue: 3, page 905-926
  • ISSN: 0373-0956

Abstract

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Let A = K [ x 1 , , x m ] be a polynomial ring in m variables and let d = ( d 0 < < d m ) be a strictly increasing sequence of m + 1 integers. Boij and Söderberg conjectured the existence of graded A -modules M of finite length having pure free resolution of type d in the sense that for i = 0 , , m the i -th syzygy module of M has generators only in degree d i .This paper provides a construction, in characteristic zero, of modules with this property that are also G L ( m ) -equivariant. Moreover, the construction works over rings of the form A K B where A is a polynomial ring as above and B is an exterior algebra.

How to cite

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Eisenbud, David, Fløystad, Gunnar, and Weyman, Jerzy. "The existence of equivariant pure free resolutions." Annales de l’institut Fourier 61.3 (2011): 905-926. <http://eudml.org/doc/219721>.

@article{Eisenbud2011,
abstract = {Let $A=K[x_1,\dots , x_m]$ be a polynomial ring in $m$ variables and let $\{\bf d\}=(d_0&lt;\cdots &lt; d_m)$ be a strictly increasing sequence of $m+1$ integers. Boij and Söderberg conjectured the existence of graded $A$-modules $M$ of finite length having pure free resolution of type $\mathbf\{d\}$ in the sense that for $i=0,\dots ,m$ the $i$-th syzygy module of $M$ has generators only in degree $d_i$.This paper provides a construction, in characteristic zero, of modules with this property that are also $GL(m)$-equivariant. Moreover, the construction works over rings of the form $A\otimes _K B$ where $A$ is a polynomial ring as above and $B$ is an exterior algebra.},
affiliation = {Dept of Mathematics Berkeley, CA 94720 (USA); Matematisk Institutt Johs. Brunsgt. 12 5008 Bergen (Norway); Northeastern University Department of Mathematics 360 Huntington Avenue Boston, MA 02115 (USA)},
author = {Eisenbud, David, Fløystad, Gunnar, Weyman, Jerzy},
journal = {Annales de l’institut Fourier},
keywords = {Pure resolution; equivariant resolution; Betti diagram; Boij-Söderberg theory; Pieri map; determinantal variety; pure resolution},
language = {eng},
number = {3},
pages = {905-926},
publisher = {Association des Annales de l’institut Fourier},
title = {The existence of equivariant pure free resolutions},
url = {http://eudml.org/doc/219721},
volume = {61},
year = {2011},
}

TY - JOUR
AU - Eisenbud, David
AU - Fløystad, Gunnar
AU - Weyman, Jerzy
TI - The existence of equivariant pure free resolutions
JO - Annales de l’institut Fourier
PY - 2011
PB - Association des Annales de l’institut Fourier
VL - 61
IS - 3
SP - 905
EP - 926
AB - Let $A=K[x_1,\dots , x_m]$ be a polynomial ring in $m$ variables and let ${\bf d}=(d_0&lt;\cdots &lt; d_m)$ be a strictly increasing sequence of $m+1$ integers. Boij and Söderberg conjectured the existence of graded $A$-modules $M$ of finite length having pure free resolution of type $\mathbf{d}$ in the sense that for $i=0,\dots ,m$ the $i$-th syzygy module of $M$ has generators only in degree $d_i$.This paper provides a construction, in characteristic zero, of modules with this property that are also $GL(m)$-equivariant. Moreover, the construction works over rings of the form $A\otimes _K B$ where $A$ is a polynomial ring as above and $B$ is an exterior algebra.
LA - eng
KW - Pure resolution; equivariant resolution; Betti diagram; Boij-Söderberg theory; Pieri map; determinantal variety; pure resolution
UR - http://eudml.org/doc/219721
ER -

References

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  13. D. Kirby, A sequence of complexes associated with a matrix, J. London Math. Soc. (2) 7 (1974), 523-530 Zbl0274.18018MR337939
  14. I. G. Macdonald, Symmetric functions and Hall polynomials, (1995), Oxford University Press, New York Zbl0487.20007MR1354144
  15. C. Peskine, L. Szpiro, Dimension projective finie et cohomologie locale. Applications à la démonstration de conjectures de M. Auslander, H. Bass et A. Grothendieck, Inst. des Hautes Études Sci. Publ. Math. (1973), 47-119 Zbl0268.13008MR374130
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