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Related papers: Notes about the Caratheodory number

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The colored Tverberg theorem asserts that for every d and r there exists t=t(d,r) such that for every set C in R^d of cardinality (d+1)t, partitioned into t-point subsets C_1,C_2,...,C_{d+1} (which we think of as color classes; e.g., the…

Combinatorics · Mathematics 2011-06-02 Jiří Matoušek , Martin Tancer , Uli Wagner

Multivariate versions of the Kronecker theorem in the continuous multivariate setting has recently been published. These theorems characterize the symbols that give rise to finite rank multidimensional Hankel and Toeplitz type operators…

Functional Analysis · Mathematics 2015-08-17 Fredrik Andersson , Marcus Carlsson

Motivated by works on extension sets in standard domains we introduce a notion of the Carath\'eodory set that seems better suited for the methods used in proofs of results on characterization of extension sets. A special stress is put on a…

Complex Variables · Mathematics 2020-02-19 Lukasz Kosinski , Wlodzimierz Zwonek

We prove the theorem mentioned in the title, for ${\mathbb{R}}^n$, where $n \ge 3$. The case of the simplex was known previously. Also, the case $n=2$ was settled, but there the infimum was some well-defined function of the side lengths. We…

Differential Geometry · Mathematics 2017-07-28 N. V. Abrosimov , E. Makai, , A. D. Mednykh , Yu. G. Nikonorov , G. Rote

We give an alternative proof of the striking new Tverberg type theorem of Blagojevic and Ziegler, arXiv:0910.4987v1 [math.CO]. Our method also yields some new cases of "constrained Tverberg thereom" in the sense of Hell, including a simple…

Combinatorics · Mathematics 2011-04-12 S. T. Vrecica , R. T. Zivaljevic

In this paper we discuss the convergence of distances associated to converging structures of Lipschitz vector fields and continuously varying norms on a smooth manifold. We prove that, under a mild controllability assumption on the limit…

Metric Geometry · Mathematics 2021-11-15 Gioacchino Antonelli , Enrico Le Donne , Sebastiano Nicolussi Golo

In this paper we consider some results on intersection between rays and a given family of convex, compact sets. These results are similar to the center point theorem, and Tverberg's theorem on partitions of a point set.

Combinatorics · Mathematics 2011-07-06 R. N. Karasev

Recent results of Hindman, Leader and Strauss and of Fern\'andez-Bret\'on and Rinot showed that natural versions of Hindman's Theorem fail {\em for all} uncontable cardinals. On the other hand, Komj\'ath proved a result in the positive…

Combinatorics · Mathematics 2025-06-12 Lorenzo Carlucci

We prove a common extension of Bang's and Kadets' lemmas for contact pairs, in the spirit of the Colourful Carath\'eodory Theorem. We also formulate a generalized version of the affine plank problem and prove it under special assumptions.…

Metric Geometry · Mathematics 2022-06-06 Gergely Ambrus

Motivated by recent results and questions of D. Raghavan and S. Shelah, we present ZFC theorems on the bounding and various almost disjointness numbers, as well as on reaping and dominating families on uncountable, regular cardinals. We…

Logic · Mathematics 2018-03-09 Vera Fischer , Daniel T. Soukup

In this paper, we prove that if $\kappa$ is a almost strongly compact cardinal, then any MAEC with L\"owenheim-Skolem number below $\kappa$ is $<\kappa$-d-tame.

Logic · Mathematics 2015-08-25 Will Boney , Pedro Zambrano

In this paper, we prove the following result : let X be a complex manifold, hyperbolic for the Carath\'eodory distance and let U be an open set relatively compact in X. Then, there exists k<1 such that we get, for the Carath\'eodory…

Complex Variables · Mathematics 2011-05-11 Jean-Pierre Vigue

The "topological Tverberg conjecture" by B\'ar\'any, Shlosman and Sz\H{u}cs (1981) states that any continuous map of a simplex of dimension $(r-1)(d+1)$ to $\mathbb{R}^d$ maps points from $r$ disjoint faces of the simplex to the same point…

Combinatorics · Mathematics 2020-06-02 Florian Frick

We derive general formula for the fourth coefficient of the functions belonging to the Carath\'{e}odory class involving the parameters lying in the open unit disk. Further, we obtain sharp upper bounds of initial inverse coefficients for…

Complex Variables · Mathematics 2020-10-08 Priyanka Goel , S. Sivaprasad Kumar

The Topological Tverberg Theorem claims that any continuous map of a (q-1)(d+1)-simplex to \R^d identifies points from q disjoint faces. (This has been proved for affine maps, for d=1, and if q is a prime power, but not yet in general.) The…

Combinatorics · Mathematics 2007-05-23 Torsten Schöneborn , Günter M. Ziegler

Using the Maskit coordinates for Teichmuller space, we prove the existence of new families of one dimensional subspaces on which the Caratheodory and Kobayashi metrics agree.

Complex Variables · Mathematics 2016-07-01 Irwin Kra

Hadwiger's transversal theorem gives necessary and sufficient conditions for a family of convex sets in the plane to have a line transversal. A higher dimensional version was obtained by Goodman, Pollack and Wenger, and recently a colorful…

Metric Geometry · Mathematics 2013-10-17 Andreas F. Holmsen , Edgardo Roldán-Pensado

We study the Carath\'eodory number of homogeneous convex cones via their spectrahedral representations. A characterization of homogeneous convex cones whose ranks match their Carath\'eodory numbers is given. This characterization is then…

Optimization and Control · Mathematics 2025-11-24 Chek Beng Chua

A closure system with the anti-exchange axiom is called a convex geometry. One geometry is called a sub-geometry of the other if its closed sets form a sublattice in the lattice of closed sets of the other. We prove that convex geometries…

Combinatorics · Mathematics 2014-01-29 Kira Adaricheva

In this paper, we prove a version of the Colored Tverberg Theorem with new constraints on the faces, in which we limit the number of faces with each one of the colors.

Combinatorics · Mathematics 2022-10-17 Leandro Vicente Mauri , Denise de Mattos , Edivaldo Lopes dos Santos