Unimodular Triangulations and Coverings of Configurations Arising from Root Systems
نویسندگان
چکیده
Existence of a regular unimodular triangulation of the configuration + ∪ {(0, 0, . . . , 0)} in Rn, where + is the collection of the positive roots of a root system ⊂Rn and where (0, 0, . . . , 0) is the origin of Rn, will be shown for = Bn, Cn, Dn and BCn . Moreover, existence of a unimodular covering of a certain subconfiguration of the configuration An+1 will be studied.
منابع مشابه
Root Polytopes and Growth Series of Root Lattices
The convex hull of the roots of a classical root lattice is called a root polytope. We determine explicit unimodular triangulations of the boundaries of the root polytopes associated to the root lattices An, Cn and Dn, and compute their f -and h-vectors. This leads us to recover formulae for the growth series of these root lattices, which were first conjectured by Conway–Mallows–Sloane and Baak...
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