Supersolvable arrangement

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In mathematics, a supersolvable arrangement is a hyperplane arrangement which has a maximal flag with only modular elements. Equivalently, the intersection semilattice of the arrangement is a supersolvable lattice, in the sense of Richard P. Stanley. [1] As shown by Hiroaki Terao, a complex hyperplane arrangement is supersolvable if and only if its complement is fiber-type. [2]

Examples include arrangements associated with Coxeter groups of type A and B.

It is known that the Orlik–Solomon algebra of a supersolvable arrangement is a Koszul algebra; whether the converse is true is an open problem. [3]

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References

  1. Stanley, Richard P. (1972). "Supersolvable lattices". Algebra Universalis . 2: 197–217. doi:10.1007/BF02945028. MR   0309815. S2CID   189844197.
  2. Terao, Hiroaki (1986). "Modular elements of lattices and topological fibration". Advances in Mathematics . 62 (2): 135–154. doi: 10.1016/0001-8708(86)90097-6 . MR   0865835.
  3. Yuzvinsky, Sergey (2001). "Orlik–Solomon algebras in algebra and topology". Russian Mathematical Surveys . 56 (2): 293–364. Bibcode:2001RuMaS..56..293Y. doi:10.1070/RM2001v056n02ABEH000383. MR   1859708.