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In this note we gather and review some facts about existence of toric spaces over 3-dimensional simple polytopes. First, over every combinatorial 3-polytope there exists a quasitoric manifold. Second, there exist combinatorial 3-polytopes,…

Algebraic Topology · Mathematics 2026-02-10 Anton Ayzenberg

It is known that for each combinatorial type of convex 3-dimensional polyhedra, there is a representative with edges tangent to the unit sphere. This representative is unique up to projective transformations that fix the unit sphere. We…

Metric Geometry · Mathematics 2007-05-23 Boris A. Springborn

A $d$-dimensional simplex in Euclidean space is called orthocentric if all of its altitudes intersect at a single point, referred to as the orthocenter. We explicitly compute the internal and external angles at all faces of an orthocentric…

Metric Geometry · Mathematics 2025-05-09 Zakhar Kabluchko , Philipp Schange

We introduce a novel intrinsic volume concept in tropical geometry. This is achieved by developing the foundations of a tropical analog of lattice point counting in polytopes. We exhibit the basic properties and compare it to existing…

Metric Geometry · Mathematics 2019-08-22 Georg Loho , Matthias Schymura

Tropicalisation (with trivial coefficients) is a process that turns a polynomial equation into a combinatorial predicate on subsets of the set of variables. We show that for each minuscule representation of a simple reductive group, there…

Combinatorics · Mathematics 2025-12-17 Kieran Calvert , Aram Dermenjian , Alex Fink , Ben Smith

Ghomi proved that every convex polyhedron could be stretched via an affine transformation so that it has an edge-unfolding to a net [Gho14]. A net is a simple planar polygon; in particular, it does not self-overlap. One can view his result…

Computational Geometry · Computer Science 2023-02-17 Joseph O'Rourke

The growth of tropical geometry has generated significant interest in the tropical semiring in the past decade. However, there are other semirings in tropical algebra that provide more information, such as the symmetrized (max, +),…

Commutative Algebra · Mathematics 2018-10-09 Sara Kalisnik Verovsek , Davorin Lesnik

Ordinary polytopes are known as a non-simplicial generalization of the cyclic polytopes. The face vectors of ordinary polytopes are shown to be log-concave.

Combinatorics · Mathematics 2011-12-09 Laszlo Major

Develin and Sturmfels showed that regular triangulations of $\Delta_{n-1} \times \Delta_{d-1}$ can be thought as tropical polytopes. Tropical oriented matroids were defined by Ardila and Develin, and were conjectured to be in bijection with…

Combinatorics · Mathematics 2010-11-12 Suho Oh , Hwanchul Yoo

For a polytope P a simplex S with vertex set V(S) is called a special simplex if every facet of P contains all but exactly one vertex of S. For such polytopes P with face complex F(P) containing a special simplex the subcomplex F(P) / V(S)…

Combinatorics · Mathematics 2010-10-01 Timo de Wolff

Polytope complexes are the generalisation of polygon meshes in geo-information systems (GIS) to arbitrary dimension, and a natural concept for accessing spatio-temporal information. Complexes of each dimension have a straight-forward…

Computational Geometry · Computer Science 2012-05-28 Norbert Paul

We state that any constant curvature Riemannian metric with conical singularities of constant sign curvature on a compact (orientable) surface $S$ can be realized as a convex polyhedron in a Riemannian or Lorentzian) space-form. Moreover…

Differential Geometry · Mathematics 2010-11-16 François Fillastre

We study the tropical version of the contraction morphism $\mathcal{T}$ between moduli spaces of stable and pseudostable curves. By promoting $\mathcal{T}$ to a logarithmic morphism, we obtain a piecewise linear function between the…

Algebraic Geometry · Mathematics 2024-04-04 Renzo Cavalieri , Steffen Marcus , Jonathan Wise

In this paper we introduce a combinatorial formula for the Ekeland-Hofer-Zehnder capacity of a convex polytope in $\mathbb{R}^{2n}$. One application of this formula is a certain subadditivity property of this capacity.

Symplectic Geometry · Mathematics 2023-09-19 Pazit Haim-Kislev

The concepts of tropical-semiring and tropical hypersurface, are extended for an arbitrary ordered group. Then, we define the tropicalization of a polynomial with coefficients in a Krull-valued field. After a close study of the properties…

Algebraic Geometry · Mathematics 2009-04-01 Fuensanta Aroca

Consider a lattice in a real finite dimensional vector space. Here, we are interested in the lattice polytopes, that is the convex hulls of finite subsets of the lattice. Consider the group $G$ of the affine real transformations which map…

Combinatorics · Mathematics 2007-05-23 Nicolas Ressayre , Pierre-Louis Montagard

We define Q-normal lattice polytopes. Natural examples of such polytopes are Cayley sums of strictly combinatorially equivalent lattice polytopes, which correspond to particularly nice toric fibrations, namely toric projective bundles. In a…

Algebraic Geometry · Mathematics 2009-04-01 Alicia Dickenstein , Sandra Di Rocco , Ragni Piene

We define arroids as an abstract axiom set encoding the intersection properties of arrangements of curves. The tropicalization of the complement of arrangement of curves meeting pairwise transversely is shown to be determined by the…

Algebraic Geometry · Mathematics 2025-08-29 Edvard Aksnes

We call complex quasifold of dimension k a space that is locally isomorphic to the quotient of an open subset of the space C^k by the holomorphic action of a discrete group; the analogue of a complex torus in this setting is called a…

Complex Variables · Mathematics 2007-05-23 Fiammetta Battaglia , Elisa Prato

A tropical complete intersection curve C in R^(n+1) is a transversal intersection of n smooth tropical hypersurfaces. We give a formula for the number of vertices of C given by the degrees of the tropical hypersurfaces. We also compute the…

Algebraic Geometry · Mathematics 2007-11-14 Magnus Dehli Vigeland