Tight Lower Bounds on the Sizes of Symmetric Extensions of Permutahedra and Similar Results
Tight Lower Bounds on the Sizes of Symmetric Extensions of Permutahedra and Similar Results
复制标题
全面体对称扩展尺寸的严格下界及类似结果
DOI:
--
复制
发表时间:
2009
影响因子:
1.7
通讯作者:
Kanstantsin Pashkovich
中科院分区:
文献类型:
--
作者:
Kanstantsin Pashkovich
It is well known that the permutahedron Πn has 2n − 2 facets. The Birkhoff polytope provides a symmetric extended formulation of Πn of size Θ(n2). Recently, Goemans described a non-symmetric extended formulation of Πn of size Θ(n log n). In this paper, we prove that Ω(n2) is a lower bound for the size of symmetric extended formulations of Πn. Moreover, we prove that the cardinality indicating polytope has the same tight lower bounds for the sizes of symmetric and nonsymmetric extended formulations as the permutahedron.