Roswitha Blind (also published as Roswitha Hammer) is a German mathematician, specializing in

convex geometry In mathematics, convex geometry is the branch of geometry studying convex sets, mainly in Euclidean space. Convex sets occur naturally in many areas: computational geometry, convex analysis, discrete geometry, functional analysis, geometry of numbe ...

discrete geometry Discrete geometry and combinatorial geometry are branches of geometry that study combinatorial properties and constructive methods of discrete geometric objects. Most questions in discrete geometry involve finite or discrete sets of basic geome ...

, and

polyhedral combinatorics Polyhedral combinatorics is a branch of mathematics, within combinatorics and discrete geometry, that studies the problems of counting and describing the faces of convex polyhedra and higher-dimensional convex polytopes. Research in polyhedral comb ...

, and a politician and organizer for the

Social Democratic Party of Germany The Social Democratic Party of Germany (german: Sozialdemokratische Partei Deutschlands, ; SPD, ) is a centre-left social democratic political party in Germany. It is one of the major parties of contemporary Germany. Saskia Esken has been the ...

Stuttgart Stuttgart (; Swabian: ; ) is the capital and largest city of the German state of Baden-Württemberg. It is located on the Neckar river in a fertile valley known as the ''Stuttgarter Kessel'' (Stuttgart Cauldron) and lies an hour from the ...

Mathematics

As Roswitha Hammer, Blind completed a Ph.D. in 1974 at the

University of Stuttgart The University of Stuttgart (german: Universität Stuttgart) is a leading research university located in Stuttgart, Germany. It was founded in 1829 and is organized into 10 faculties. It is one of the oldest technical universities in Germany wit ...

. Her dissertation, ''Über konvexe Strukturen und die Beziehungen zur elementaren Konvexität'', concerned

and

and was supervised by

Kurt Leichtweiss Kurt Leichtweiß (March 2, 1927 in Villingen-Schwenningen – June 23, 2013) was a mathematician specializing in convex and differential geometry. In 1944, while still in high school Leichtweiß traveled to the Oberwolfach Research Institute for ...

. She is best known in mathematics for a 1987 publication with Peter Mani-Levitska in which, solving a conjecture of

Micha Perles Micah (; ) is a given name. Micah is the name of several people in the Hebrew Bible ( Old Testament), and means "Who is like God?" The name is sometimes found with theophoric extensions. Suffix theophory in '' Yah'' and in ''Yahweh'' results in ...

, she and Mani-Levitska proved that the combinatorial structure of

simple polytope In geometry, a -dimensional simple polytope is a -dimensional polytope each of whose vertices are adjacent to exactly edges (also facets). The vertex figure of a simple -polytope is a - simplex. Simple polytopes are topologically dual to s ...

s is completely determined by their graphs. This result has been called the Blind–Mani theorem or the Perles–Blind–Mani theorem. In a 1979 publication, she introduced a class of

convex polytope A convex polytope is a special case of a polytope, having the additional property that it is also a convex set contained in the n-dimensional Euclidean space \mathbb^n. Most texts. use the term "polytope" for a bounded convex polytope, and the wo ...

s sometimes called the Blind polytopes, generalizing the

semiregular polytope In geometry, by Thorold Gosset's definition a semiregular polytope is usually taken to be a polytope that is vertex-transitive and has all its facets being regular polytopes. E.L. Elte compiled a longer list in 1912 as ''The Semiregular Polytop ...

s and

Johnson solid In geometry, a Johnson solid is a strictly convex polyhedron each face of which is a regular polygon. There is no requirement that isohedral, each face must be the same polygon, or that the same polygons join around each Vertex (geometry), ver ...

s, in which all faces are

regular polytope In mathematics, a regular polytope is a polytope whose symmetry group acts transitively on its flags, thus giving it the highest degree of symmetry. All its elements or -faces (for all , where is the dimension of the polytope) — cells, f ...

Politics

Blind became a city councillor in the Möhringen-Vaihingen district of

in 2004, stepping down from that seat in 2009 in order to become chair of the

local council group. As councillor, in order to better serve the youth of her district, she became chair of a local football club, 1. FC Lauchhau-Lauchäcker, in 2006, also serving as president of the Stuttgart Sports Forum. She retired from politics in 2014, and from her position with the football club in 2016.

References

{{DEFAULTSORT:Blind, Roswitha Year of birth missing (living people) Living people 20th-century German mathematicians German women mathematicians University of Stuttgart alumni Politicians from Stuttgart 21st-century German mathematicians