Ruth Kellerhals (born 17 July 1957) is a Swiss mathematician at the

University of Fribourg The University of Fribourg (french: Université de Fribourg; german: Universität Freiburg) is a public university located in Fribourg, Switzerland. The roots of the university can be traced back to 1580, when the notable Jesuit Peter Canisius ...

, whose field of study is

hyperbolic geometry In mathematics, hyperbolic geometry (also called Lobachevskian geometry or Bolyai– Lobachevskian geometry) is a non-Euclidean geometry. The parallel postulate of Euclidean geometry is replaced with: :For any given line ''R'' and point ''P'' ...

geometric group theory Geometric group theory is an area in mathematics devoted to the study of finitely generated groups via exploring the connections between algebraic properties of such group (mathematics), groups and topology, topological and geometry, geometric pro ...

and polylogarithm identities.

Biography

As a child, she went to a gymnasium in Basel and then studied at the

University of Basel The University of Basel (Latin: ''Universitas Basiliensis'', German: ''Universität Basel'') is a university in Basel, Switzerland. Founded on 4 April 1460, it is Switzerland's oldest university and among the world's oldest surviving universit ...

, graduating in 1982 with a diploma directed by Heinz Huber "On finiteness of the isometry group of a compact negatively curved Riemannian manifold". She received her PhD in 1988, from the same university, with a thesis entitled "On the volumes of hyperbolic polytopes in dimensions three and four". Her advisor was Hans-Christoph Im Hof. During the year 1983–84 she also studied at the

University of Grenoble The Université Grenoble Alpes (UGA, French: meaning "''Grenoble Alps University''") is a public research university in Grenoble, France. Founded in 1339, it is the third largest university in France with about 60,000 students and over 3,000 resea ...

( Fourier Institute). In 1995 she received her habilitation from the

University of Bonn The Rhenish Friedrich Wilhelm University of Bonn (german: Rheinische Friedrich-Wilhelms-Universität Bonn) is a public research university located in Bonn, North Rhine-Westphalia, Germany. It was founded in its present form as the ( en, Rhine U ...

, where she worked at the

Max Planck Institute for Mathematics The Max Planck Institute for Mathematics (german: Max-Planck-Institut für Mathematik, MPIM) is a prestigious research institute located in Bonn, Germany. It is named in honor of the German physicist Max Planck and forms part of the Max Planck S ...

since 1989 until 1995. There, she was an assistant with Professor

Friedrich Hirzebruch Friedrich Ernst Peter Hirzebruch ForMemRS (17 October 1927 – 27 May 2012) was a German mathematician, working in the fields of topology, complex manifolds and algebraic geometry, and a leading figure in his generation. He has been described as ...

. Since 1995 she has been an assistant professor at the

University of Göttingen The University of Göttingen, officially the Georg August University of Göttingen, (german: Georg-August-Universität Göttingen, known informally as Georgia Augusta) is a public research university in the city of Göttingen, Germany. Founded ...

, and since 1999 a distinguished professor at the

University of Bordeaux 1 The University of Bordeaux 1 (french: Université Bordeaux-I) was one of the four universities in the Academy of Bordeaux, together with the Bordeaux Segalen University (Bordeaux 2), Michel de Montaigne University (Bordeaux 3) and Montesquieu ...

. In 2000 she became a professor at the

, Switzerland, where she was in 1998 to 1999 as a visiting professor.

Research

Her main research fields include hyperbolic geometry, geometric group theory, geometry of

discrete group In mathematics, a topological group ''G'' is called a discrete group if there is no limit point in it (i.e., for each element in ''G'', there is a neighborhood which only contains that element). Equivalently, the group ''G'' is discrete if and on ...

s (especially

reflection group In group theory and geometry, a reflection group is a discrete group which is generated by a set of reflections of a finite-dimensional Euclidean space. The symmetry group of a regular polytope or of a tiling of the Euclidean space by congruent cop ...

Coxeter group In mathematics, a Coxeter group, named after H. S. M. Coxeter, is an abstract group that admits a formal description in terms of reflections (or kaleidoscopic mirrors). Indeed, the finite Coxeter groups are precisely the finite Euclidean refl ...

s), convex and polyhedral geometry, volumes of hyperbolic polytopes, manifolds and polylogarithms. She does historical research into the works and life of

Ludwig Schläfli Ludwig Schläfli (15 January 1814 – 20 March 1895) was a Swiss mathematician, specialising in geometry and complex analysis (at the time called function theory) who was one of the key figures in developing the notion of higher-dimensional space ...

, a Swiss

geometer A geometer is a mathematician whose area of study is geometry. Some notable geometers and their main fields of work, chronologically listed, are: 1000 BCE to 1 BCE * Baudhayana (fl. c. 800 BC) – Euclidean geometry, geometric algebra * ...

.''Der Mathematiker Ludwig Schläfli (15.01.1814 – 20.03.1895)'', DMV-Mitteilungen 4 (1996), 35–43, ''Ludwig Schläfli – ein genialer Schweizer Mathematiker'', Elem. Math. 65 (2010), 165–177 She has been a guest researcher at MSRI, IHES,

Mittag-Leffler Institute The Mittag-Leffler Institute is a mathematical research institute located in Djursholm, a suburb of Stockholm. It invites scholars to participate in half-year programs in specialized mathematical subjects. The Institute is run by the Royal Swe ...

, the

State University of New York at Stony Brook Stony Brook University (SBU), officially the State University of New York at Stony Brook, is a public research university in Stony Brook, New York. Along with the University at Buffalo, it is one of the State University of New York system's ...

, RIMS in Kyoto,

Osaka City University , abbreviated to , is a public university in Japan. It is located in Sumiyoshi-ku, Osaka. It is one of the most prestigious universities in Japan regarding Applied Linguistics. The university will merge with Osaka Prefecture University to form O ...

ETH Zürich (colloquially) , former_name = eidgenössische polytechnische Schule , image = ETHZ.JPG , image_size = , established = , type = Public , budget = CHF 1.896 billion (2021) , rector = Günther Dissertori , president = Joël Mesot , ac ...

, the

University of Bern The University of Bern (german: Universität Bern, french: Université de Berne, la, Universitas Bernensis) is a university in the Switzerland, Swiss capital of Bern and was founded in 1834. It is regulated and financed by the Canton of Bern. It ...

and the

University of Auckland , mottoeng = By natural ability and hard work , established = 1883; years ago , endowment = NZD $293 million (31 December 2021) , budget = NZD $1.281 billion (31 December 2021) , chancellor = Cecilia Tarrant , vice_chancellor = Dawn F ...

. Also she visited numerous research institutes and universities in Helsinki, Berlin and Budapest.

Selected works

* * * * * * * * * *

References

External links

Homepage
{{DEFAULTSORT:Kellerhals, Ruth 1957 births Living people Swiss mathematicians Swiss women mathematicians University of Basel alumni Academic staff of the University of Fribourg