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Related papers: Permutohedron's volume via Dyck paths

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We derive an explicit formula for the volume of a regular simplex in the hyperbolic space of any dimension.

Metric Geometry · Mathematics 2025-11-18 Zakhar Kabluchko , Philipp Schange

We study the poset topology of lattices arising from orientations of 1-skeleta of directionally simple polytopes, with Bruhat interval polytopes $Q_{e,w}$ as our main example. We show that the order complex $\Delta ((u,v)_w)$ of an interval…

Combinatorics · Mathematics 2026-03-02 Christian Gaetz , Patricia Hersh

We revisit $R$-polynomials with introducing the new idea ``shifted $R$-polynomials" (or Bruhat weight) for all Bruhat intervals in finite Coxeter groups. Then, we apply these polynomials to weighted counting of Bruhat paths. Further, we…

Combinatorics · Mathematics 2019-07-30 Masato Kobayashi

The face lattice of the permutohedron realizes the combinatorics of linearly ordered partitions of the set $[n]=\{1,...,n\}$. Similarly, the cyclopermutohedron is a virtual polytope that realizes the combinatorics of cyclically ordered…

Metric Geometry · Mathematics 2015-05-05 Ilya Nekrasov , Gaiane Panina

The volume of a cyclic polytope can be obtained by forming an iterated integral along a suitable piecewise linear path running through its edges. Different choices of such a path are related by the action of a subgroup of the combinatorial…

Rings and Algebras · Mathematics 2025-06-03 Felix Lotter , Rosa Preiß

Let n >= 2 be an integer and consider the set T_n of n by n permutation matrices pi for which pi_{ij}=0 for j>=i+2. In this paper we study the convex hull of T_n, which we denote by P_n. P_n is a polytope of dimension binom{n}{2}. Our main…

Combinatorics · Mathematics 2007-05-23 Clara S. Chan , David P. Robbins , David S. Yuen

Volume computation for $d$-polytopes $\mathcal{P}$ is fundamental in mathematics. There are known volume computation algorithms, mostly based on triangulation or signed-decomposition of $\mathcal{P}$. We consider $…

Combinatorics · Mathematics 2024-01-09 Guoce Xin , Xinyu Xu , Yingrui Zhang , Zihao Zhang

It has been recently conjectured that scattering amplitudes in planar N=4 super Yang-Mills are given by the volume of the (dual) amplituhedron. In this paper we show some interesting connections between the tree-level amplituhedron and a…

High Energy Physics - Theory · Physics 2016-03-23 Livia Ferro , Tomasz Lukowski , Andrea Orta , Matteo Parisi

We introduce new families of combinatorial objects whose enumeration computes volumes of flow polytopes. These objects provide an interpretation, based on parking functions, of Baldoni and Vergne's generalization of a volume formula…

The geometry of the dual amplituhedron is generally described in reference to a particular triangulation. A given triangulation manifests only certain aspects of the underlying space while obscuring others, therefore understanding this…

High Energy Physics - Theory · Physics 2017-08-22 Michael Enciso

We present a relation between volumes of certain lower dimensional simplices associated to a full-dimensional primal and polar dual polytope in R^k. We then discuss an application of this relation to a geometric construction of a Colin de…

Combinatorics · Mathematics 2024-10-04 Ioannis Ivrissimtzis , Carsten Lange , Shiping Liu , Norbert Peyerimhoff

Partial permutohedra are lattice polytopes which were recently introduced and studied by Heuer and Striker. For positive integers $m$ and $n$, the partial permutohedron $\mathcal{P}(m,n)$ is the convex hull of all vectors in…

This paper proves the volume of the arithmetic Okounkov body, constructed from a hermitian line bundle on an arithmetic variety by the author in a previous paper, is equal to the the volume of the hermitian line bundle up to a simple…

Number Theory · Mathematics 2012-01-12 Xinyi Yuan

We define and study the dual mixed volume rational function of a sequence of polytopes, a dual version of the mixed volume polynomial. This concept has direct relations to the adjoint polynomials and the canonical forms of polytopes. We…

Combinatorics · Mathematics 2024-10-30 Yibo Gao , Thomas Lam , Lei Xue

This is the second of two papers where we study polytopes arising from affine Coxeter arrangements. Our results include a formula for their volumes, and also compatible definitions of hypersimplices, descent numbers and major index for all…

Combinatorics · Mathematics 2012-02-20 Thomas Lam , Alexander Postnikov

Answering a question of Gamarnik and Smedira, we give a polynomial time algorithm that approximately computes the volume of a truncation of a relaxation of the independent set polytope, improving on their quasi-polynomial time algorithm.…

Combinatorics · Mathematics 2024-04-15 Ferenc Bencs , Guus Regts

In this paper, we consider the volume of a special kind of flow polytope. We show that its volume satisfies a certain system of differential equations, and conversely, the solution of the system of differential equations is unique up to a…

Combinatorics · Mathematics 2019-04-11 Takayuki Negishi , Yuki Sugiyama , Tatsuru Takakura

Recently in arXiv:2012.05599 Rudenko presented a formula for the volume of hyperbolic orthoschemes in terms of alternating polylogarithms. We use this result to provide an explicit analytic result for the one-loop scalar n-gon Feynman…

High Energy Physics - Theory · Physics 2024-04-15 Lecheng Ren , Marcus Spradlin , Cristian Vergu , Anastasia Volovich

Let the \emph{double hyperbolic space} $\mathbb{DH}^n$, proposed in this paper as an extension of the hyperbolic space $\mathbb{H}^n$, contain a two-sheeted hyperboloid with the two sheets connected to each other along the boundary at…

Metric Geometry · Mathematics 2022-04-05 Lizhao Zhang

A generalized hyperbolic tetrahedra is a polyhedron (possibly non-compact) with finite volume in hyperbolic space, obtained from a tetrahedron by the polar truncation at the vertices lying outside the space. In this paper it is proved that…

Geometric Topology · Mathematics 2007-05-23 Akira Ushijima