Abstract
Certain problems on reducibility of central hyperplane arrangements are settled. Firstly, a necessary and sufficient condition on reducibility is obtained. More precisely, it is proved that the number of irreducible components of a central hyperplane arrangement equals the dimension of the space consisting of the logarithmic derivations of the arrangement with degree zero or one. Secondly, it is proved that the decomposition of an arrangement into a direct sum of its irreducible components is unique up to an isomorphism of the ambient space. Thirdly, an effective algorithm for determining the number of irreducible components and decomposing an arrangement into a direct sum of its irreducible components is offered. This algorithm can decide whether an arrangement is reducible, and if it is the case, what the defining equations of irreducible components are.
Similar content being viewed by others
References
Orlik P, Terao H. Arrangements of Hyperplanes. Berlin-Heidelberg: Springer-Verlag, 1992
Cordovil R. On the center of the fundamental group of the complement of a hyperplane arrangement. Portugaliae Mathematica, 51: 363–373 (1994)
Cohen D, Suciu A. On Milnor fibrations of arrangements. J Lodon Math Soc, 51: 105–119 (1995)
Cohen D, Orlik P. Some cyclic covers of complements of arrangements. Topology & Appl, 118: 3–15 (2002)
Cohen D, Orlik P. Gauss-Manin connections for arrangements, I. Eigenvalues. Compositio Math, 136:299–316 (2003)
Cohen D, Orlik P. Gauss-Manin connections for arrangements, II. Nonresonant weights. Amer J Math, 127: 569–594 (2005)
Cohen D, Orlik P. Gauss-Manin connections for arrangements, III. Formal connections. Trans Amer Math Soc, 357: 3031–3050 (2005)
Cohen D, Orlik P. Gauss-Manin connections for arrangements, IV. Nonresonant eigenvalus. Comment Math Helv, 81(4): 883–909 (2006)
Aomoto A, Kita M. Hypergeometric Functions (in Japanese). Tokyo: Springer-Verlag, 1994
Orlik P, Terao H. Arrangements and hypergeometric integrals. MSJ Memoir 9, Tokyo: Mathematical Society of Japan, 2001
Schechtman V, Varchenko A N. Arrangements of hyperplanes and Lie algebra homology. Invent Math, 106:139–194 (1991)
Varchenko A N. Multidimensional hypergeometric functions and representation theory of Lie groups. Advanced Studies in Mathematical Physics. Vol. 21, Singapore: World Scientific Publishers, 1995
Esnault H, Schechtman V, Viehweg E. Cohomology of local systems of the complement of hyperplanes. Invent Math, 109: 557–561 (1992); Erratum, ibid. 112: 447 (1993)
Schechtman V, Terao H, Varchenko A N. Local systems over complements of hyperplanes and the Kac-Kazhdan conditions for singular vectors. J Pure and App Alg, 100: 93–102 (1995)
Falk M, Terao H. β nbc-bases for cohomology of local systems on hyperplane complements. Trans Amer Math Soc, 349: 189–202 (1997)
Aramova A, Avramov L A, Herzog J. Resolutions of monomial ideals and cohomology over exterior algebras. Trans Amer Math Soc, 352: 579–594 (2000)
Eisenbud D, Popescu S, Yuzvinsky S. Hyperplane arrangements cohomology and monomials in the exterior algebra. Trans Amer Math Soc, 355(11): 4365–4383 (2003)
Yuzvinsky S. Orlik-Solomon algebra in algebra and topology. Russian Math Surveys, 56(2): 293–364 (2001)
Crapo H. A higher invariant for matroids. J Combinatorial Theory, 2: 406–417 (1967)
Author information
Authors and Affiliations
Corresponding author
Additional information
This work was partially supported by the National Natural Science Foundation of China (Grant No. 10671009)
Rights and permissions
About this article
Cite this article
Jiang, Gf., Yu, Jm. Reducibility of hyperplane arrangements. SCI CHINA SER A 50, 689–697 (2007). https://doi.org/10.1007/s11425-007-2075-z
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/s11425-007-2075-z