ScalingStacks

Remark 1.15 . [04RP]

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Remark 1.15.

The concept of generic polyhedron is closely related to that of special spine in Topology. We remind its definition. Let MM be a compact (n+1)(n+1)-manifold with boundary and Π¯⊂M\bar{\Pi}\subset M be an nn-dimensional CW-complex such that its every open cell is smoothly embedded to MM. The complex Π¯\bar{\Pi} is called a spine of MM if Π¯\bar{\Pi} is a deformational retract of MM. The spine Π¯\bar{\Pi} is called special if for any point x∈Π¯∖∂Mx\in\bar{\Pi}\smallsetminus\partial M from an open kk-cell there exists a neighborhood isomorphic to ℝk×Σn−k\mathbb{R}^{k}\times\Sigma^{n-k}.

Note that if Int⁡Δ∩ℤn+1=∅\operatorname{Int}\Delta\cap\mathbb{Z}^{n+1}=\emptyset then all the triangulation vertices of a dual Δ\Delta-polyhedron Π\Pi are from ∂Δ\partial\Delta then Π¯\bar{\Pi} is a spine of Δ\Delta. In general, Π¯\bar{\Pi} is a spine of the polyhedron Δ\Delta minus a small neighborhood of the interior lattice points. Note that Π¯\bar{\Pi} can be treated as a special spine of Δ\Delta if we treat Δ\Delta as a manifold with boundary and corners.

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