Skip to main content
Search type Search syntax
Tags [tag]
Exact "words here"
Author user:1234
user:me (yours)
Score score:3 (3+)
score:0 (none)
Answers answers:3 (3+)
answers:0 (none)
isaccepted:yes
hasaccepted:no
inquestion:1234
Views views:250
Code code:"if (foo != bar)"
Sections title:apples
body:"apples oranges"
URL url:"*.example.com"
Saves in:saves
Status closed:yes
duplicate:no
migrated:no
wiki:no
Types is:question
is:answer
Exclude -[tag]
-apples
For more details on advanced search visit our help page
Results tagged with
Search options not deleted user 19864

Convex polytopes are the convex hulls of a finite set of points in Euclidean spaces. They have rich combinatorial, arithmetic, and metrical theory, and are related to toric varieties and to linear programming

1 vote

Permutohedron and triangulation of cube via Eulerian numbers

One context in which this relationship between the hypercube and the permutahedron appears is as follows. The space of weights of the Lie algebra $\mathfrak{sl}_n$ is naturally identified with $\mathb …
Igor Makhlin's user avatar
  • 3,513
6 votes
0 answers
181 views

Looking for the correct version of a wrong statement from Barvinok's book on convex polyhedra

The book I'm concerned with is "Integer Points in Polyhedra" by A. Barvinok, which, I must say, is turning out to be highly fascinating. A real finite-dimensional vector space $V$ defines the followi …
Igor Makhlin's user avatar
  • 3,513
5 votes
0 answers
136 views

Face structures of chain polytopes

For a finite poset $P$ the chain polytope $\mathscr C(P)\subset\mathbb{R}^P$ consists of such $g$ that $g(p)\ge 0$ for all $p\in P$ and $$g(p_1)+\ldots+g(p_n)\le 1$$ for any chain $p_1<\ldots<p_n$. I …
Igor Makhlin's user avatar
  • 3,513
3 votes
0 answers
178 views

Zeros of Hilbert series of affine toric varieties

Consider a convex rational polyhedral cone $C\subset\mathbb R^m$ with vertex at the origin. Let $X$ be the corresponding affine toric variety, i.e. $\mathbb C[X]=\mathbb C[\mathbb Z^m\cap C^\circ]$. N …
Igor Makhlin's user avatar
  • 3,513
3 votes
2 answers
270 views

Formalization (and background) of a formula, concering the integral points of a polygon.

I have recently become aware of the following neat statement. Consider a convex polygon $P$ in the real plane with integral vertices. If we associate with every integral point $(a,b)$ the monomial $x …
Igor Makhlin's user avatar
  • 3,513
6 votes
2 answers
276 views

"Minimal" connected matroids

I'm interested in connected matroids $M$ on the ground set $[n]$ for which there is no connected matroid on $[n]$ of the same rank but with a strictly smaller set of bases (by inclusion). Equivalently …
Igor Makhlin's user avatar
  • 3,513
4 votes
0 answers
158 views

Reference for the notion of polyhedra "degenerations"

Let $P$ be a convex polyhedron and let $P(t)$ be a continuous deformation thereof, such that: a) $P(0)=P$; b) for all $t\in[0;1)$ the polyhedron $P(t)$ is strongly combinatorially equivalent to $P$ …
Igor Makhlin's user avatar
  • 3,513
1 vote

Integer decomposition property with a partial order

Just stumbled upon this question, pardon the necropost. There exist broad families of poset polytopes generalizing order and chain polytopes. These are known to have your IDP$\le$ property. The first …
Igor Makhlin's user avatar
  • 3,513
1 vote
0 answers
137 views

References/applications/context for certain polytopes

First, let's consider an almost trivial notion. With any subspace $V\subset \mathbb R^n$ we associate a convex polytope $P(V)\subset V^*$ as follows. Each of the $n$ coordinates in $\mathbb R^n$ is a …
Igor Makhlin's user avatar
  • 3,513