New posts in convex-geometry

When is a polyhedron uniquely determined by its projections?

geometry convex-geometry polyhedra combinatorial-geometry polytopes

What exactly does a compact convex set mean.?

convex-geometry

Volume of the intersection of the unit ball with a polyhedral cone

linear-algebra lebesgue-measure volume convex-geometry convex-cone

Structure of the convex hull of $n$-dimensional 0/1 vectors with exactly $k$ 1s.

convex-analysis coding-theory convex-geometry discrete-geometry

Convex function is proper when it has at least one finite value in the relative interior of its effective domain

analysis convex-analysis convex-optimization convex-geometry variational-analysis

The image of every strictly non-expanding map between spheres is contained in an open hemisphere?

geometry lipschitz-functions convex-geometry convex-hulls contraction-operator

Meaning cone, ray, fan for polytopes

linear-algebra matrices polytopes convex-geometry convex-hulls

What are the main ideas needed to prove that only $92$ Johnson solids exist?

polyhedra convex-geometry

Convexifying a Concave Polygon by Reflections

geometry convex-analysis euclidean-geometry convex-geometry convex-hulls

Surface of the intersection of $n$ balls

geometry surfaces combinatorial-geometry spheres convex-geometry

Inscribing Platonic solids in each other: why can't you put a dodecahedron in an octahedron?

geometry alternative-proof convex-geometry polyhedra platonic-solids

Can the perimeter of a convex polygon X be an odd number?

geometry polygons convex-geometry

Can any two disjoint nonempty convex sets in a vector space be separated by a hyperplane?

linear-algebra functional-analysis convex-geometry

Find the polar set of $\{(x,y)\in\mathbb R^2: x^2+y^4\le1\}$

convex-analysis convex-geometry

$ a+b+c=0,\ a^2+b^2+c^2=1$ implies $ a^4+b^4+c^4=\frac{1}{2}$

algebra-precalculus riemannian-geometry convex-geometry

Maximum area of triangle inside a convex polygon

combinatorics polyhedra combinatorial-geometry extremal-combinatorics convex-geometry

How is the subdifferential of the $l_2$ norm at $x=0$ the polar of the unit ball?

convex-analysis convex-optimization convex-geometry convex-hulls

A set of points is contained in a sphere $S$. When is $S$ also the circumsphere?

euclidean-geometry spheres convex-geometry convex-hulls metric-geometry

How can we define convexity in one dimension?

convex-analysis convex-geometry

Stable strict local minimum implies local convexity

convex-analysis convex-geometry non-convex-optimization