Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-11-26T21:13:27.662Z Has data issue: false hasContentIssue false

Iterated fiber polytopes

Published online by Cambridge University Press:  26 February 2010

Louis J. Billera
Affiliation:
Department of Mathematics, Cornell University, Ithaca, New York 14853, U.S.A.
Bernd Sturmfels
Affiliation:
Department of Mathematics, Cornell University, Ithaca, New York 14853, U.S.A.
Get access

Abstract

The construction of the fiber polytope ∑(P, Q) of a projection π:PQ of polytopes is extended to flags of projections. While the faces of the fiber polytope are related to subdivisions of Q induced by the faces of P, those of an iterated fiber polytope are related to discrete homotopies between polyhedral subdivisions. In particular, in the case of projections

starting with an (n + 1)-simplex, vertices of the successive iterates correspond to, respectively, subsets, permutations and sequences of permutations of an n-set. The first iterate will always be combinatorially an n-cube, and, under certain conditions, the second will have the structure of the (n−1)-dimensional permutohedron.

Type
Research Article
Copyright
Copyright © University College London 1994

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Baues, H. J.. Geometry of loop spaces and the cobar construction. Mem. Amer. Math. Soc., 25 (1980), No. 230.Google Scholar
2.Billera, L. J., Filliman, P. and Sturmfels, B.. Constructions and complexity of secondary polytopes. Advances in Mathematics, 83 (1990), 155179.CrossRefGoogle Scholar
3.Billera, L. J., Kapranov, M. M. and Sturmfels, B.. Cellular strings on polytopes. Proc. Amer. Math. Soc., 122 (1994), to appear.CrossRefGoogle Scholar
4.Billera, L. J. and Sturmfels, B.. Fiber polytopes. Annals of Math., 135 (1992), 527549.CrossRefGoogle Scholar
5.Björner, A., Vergnas, M. Las, Sturmfels, B., White, N., Ziegler, G.. Oriented Matroids (Cambridge University Press, 1993).Google Scholar
6.Filliman, P.. Exterior algebra and projections of polytopes. Discrete Comput. Geometry, 5 (1990), 305322.CrossRefGoogle Scholar
7.Gel'fand, I. M., Kapranov, M. M. and Zelevinsky, A. V.. Newton polytopes of the classical resultant and discriminant. Advances in Mathematics, 84 (1990), 237254.CrossRefGoogle Scholar
8.Gel'fand, I. M., Zelevinsky, A. V. and Kapranov, M. M.. Discriminants of polynomials in several variables and triangulations of Newton polyhedra. Algebra i Analiz, 2 (1990), 162. (English translation in Leningrad Math. J., 2 (1991), 449-505.)Google Scholar
9.Kapranov, M. M., Sturmfels, B. and Zelevinsky, A.. Quotients of toric varieties. Mathem. Annalen, 290 (1991), 643655.CrossRefGoogle Scholar
10.Massey, W. S.. Singular homology theory (Springer-Verlag, New York, 1980).CrossRefGoogle Scholar
11.Sleator, D. D., Tarjan, R. E. and Thurston, W. P.. Rotation distance, triangulations, and hyperbolic geometry. J. American Math. Soc., 1 (1988), 647681.CrossRefGoogle Scholar
12.Yemelichev, V. A., Kovalev, M. M. and Kravtsov, M. K.. Polytopes, Graphs and Optimisation (Cambridge University Press, 1984).Google Scholar
13.Gel'fand, I. M., Kapranov, M. M. and Zelevinsky, A. V.. Discriminants, Resultants and Multi-dimensional Determinants (Birkhaüser, Boston, 1994).CrossRefGoogle Scholar