Equilateral, diametral, centered sets and subsets of spheres.
Equilateral simplices in normed 4-space.
Equilibria in a class of games and topological results implying their existence.
We survey results related to the problem of the existence of equilibria in some classes of infinitely repeated two-person games of incomplete information on one side, first considered by Aumann, Maschler and Stearns. We generalize this setting to a broader one of principal-agent problems. We also discuss topological results needed, presenting them dually (using cohomology in place of homology) and more systematically than in our earlier papers.
Equivalence classes of Latin squares and nets in
The fundamental combinatorial structure of a net in is its associated set of mutually orthogonal Latin squares. We define equivalence classes of sets of orthogonal Latin squares by label equivalences of the lines of the corresponding net in . Then we count these equivalence classes for small cases. Finally we prove that the realization spaces of these classes in are empty to show some non-existence results for 4-nets in .
Équivalences concernant la séparation de plusieurs cônes convexes
Equivariant classification of 2-torus manifolds
We consider locally standard 2-torus manifolds, which are a generalization of small covers of Davis and Januszkiewicz and study their equivariant classification. We formulate a necessary and sufficient condition for two locally standard 2-torus manifolds over the same orbit space to be equivariantly homeomorphic. This leads us to count the equivariant homeomorphism classes of locally standard 2-torus manifolds with the same orbit space.
Equivariant fiber polytopes.
Erdős-Mordell inequality for space n-gons.
Errata to the paper "Families of convex sets closed under intersection, homotheties and uniting increasing sequences of sets" Fundamenta Mathematicae 120 (1984), pp. 14-40
Erratum : Closures of faces of compact convex sets
Erratum to: Covering the unit cube by equal balls.
Erratum to “Eigenvalues of GUE minors" [Electron. J. Probab. 11, 1342–1371 (2006; Zbl 1127.60047)].
Espace de liberté d’un sous-ensemble convexe de
Essentially-Euclidean convex bodies
In this note we introduce a notion of essentially-Euclidean normed spaces (and convex bodies). Roughly speaking, an n-dimensional space is λ-essentially-Euclidean (with 0 < λ < 1) if it has a [λn]-dimensional subspace which has further proportional-dimensional Euclidean subspaces of any proportion. We consider a space X₁ = (ℝⁿ,||·||₁) with the property that if a space X₂ = (ℝⁿ,||·||₂) is "not too far" from X₁ then there exists a [λn]-dimensional subspace E⊂ ℝⁿ such that E₁ = (E,||·||₁) and...
Estimates for the Minimal Width of Polytopes Inscribed in Convex Bodies.
Estimates on inner and outer radii of unit balls in normed spaces
The purpose of this paper is to continue the investigations on extremal values for inner and outer radii of the unit ball of a finite-dimensional real Banach space for the Holmes-Thompson and Busemann measures. Furthermore, we give a related new characterization of ellipsoids in via codimensional cross-section measures.
Estimating an even spherical measure from its sine transform
To reconstruct an even Borel measure on the unit sphere from finitely many values of its sine transform a least square estimator is proposed. Applying results by Gardner, Kiderlen and Milanfar we estimate its rate of convergence and prove strong consistency. We close this paper by giving an estimator for the directional distribution of certain three-dimensional stationary Poisson processes of convex cylinders which have applications in material science.
Estimating the diameter of the space of planar convex figures with respect to an affine-invariant metric.
Étude des différences de corps convexes plans
We characterize the linear space ℋ of differences of support functions of convex bodies of 𝔼² and we consider every h ∈ ℋ as the support function of a generalized hedgehog (a rectifiable closed curve having exactly one oriented support line in each direction). The mixed area (for plane convex bodies identified with their support functions) has a symmetric bilinear extension to ℋ which can be interpreted as a mixed area for generalized hedgehogs. We study generalized hedgehogs and we extend the...
Euclidean arrangements in Banach spaces
We study the way in which the Euclidean subspaces of a Banach space fit together, somewhat in the spirit of the Kashin decomposition. The main tool that we introduce is an estimate regarding the convex hull of a convex body in John's position with a Euclidean ball of a given radius, which leads to a new and simplified proof of the randomized isomorphic Dvoretzky theorem. Our results also include a characterization of spaces with nontrivial cotype in terms of arrangements of Euclidean subspaces.