ScalingStacks

Notation 3.103 . [02NX]

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Notation 3.103.

Let Λ\Lambda be a rational polyhedron in MℝM_{\mathbb{R}} and aff⁡(Λ)\operatorname{aff}(\Lambda) its affine hull. We denote by LΛL_{\Lambda} the linear subspace of MℝM_{\mathbb{R}} associated to aff⁡(Λ)\operatorname{aff}(\Lambda) and by M⁡(Λ)M(\Lambda) the induced lattice M∩LΛM\cap L_{\Lambda}. By definition, volM⁡(Λ)\operatorname{vol}_{M(\Lambda)} is a measure on LΛL_{\Lambda}, and we will denote also by volM⁡(Λ)\operatorname{vol}_{M(\Lambda)} the measure induced on aff⁡(Λ)\operatorname{aff}(\Lambda). If v∈Nℝv\in N_{\mathbb{R}} is orthogonal to LΛL_{\Lambda}, we define ⟨v,Λ⟩=⟨v,x⟩\langle v,\Lambda\rangle=\langle v,x\rangle for any x∈Λx\in\Lambda. Furthermore, when dim(Λ)=n\dim(\Lambda)=n and FF is a facet of Λ\Lambda, we will denote by vF∈Nv_{F}\in N the vector of minimal length that is orthogonal to LFL_{F} and satisfies ⟨vF,F⟩≤⟨vF,x⟩\langle v_{F},F\rangle\leq\langle v_{F},x\rangle for each x∈Λx\in\Lambda. In other words, vFv_{F} is the minimal inner integral orthogonal vector of FF as a facet of Λ\Lambda.

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