Roland Zumkeller's Web Page

About me

At the moment I'm mostly gardening.

In a former life I used to work in finance, mostly writing programs in Haskell.

In another former life I was a postdoc in Pitt's math department, working on the Flyspeck project. Before then I studied and worked in the TypiCal project at Ecole Polytechnique, and also at the Microsoft Research INRIA Joint Centre, both near Paris. My research interests are formal methods and global optimization.


I've developped optimization methods based on Bernstein polynomials, aiming at a formal verification of the non-linear inequalities occurring in Tom Hales' proof of the Kepler conjecture. A Haskell implementation is available below. The latest changes to it are listed here.


In fall 2009 and spring 2010 I taught MATH 0280: Introduction to Matrices and Linear Algebra.


Sergei - A global optimization tool based on Bernstein polynomials, written in Haskell.
Naufrage - A tool for sum of squares (S.O.S) decomposition of polynomials. This highly experimental implementation is in OCaml.
Texcaml - a tool to insert TeX into OCaml comments.
Cucumber - the Coq version of Sergei (outdated).


A Revision of the Proof of the Kepler Conjecture (Thomas Hales, John Harrison, Sean McLaughlin, Tobias Nipkow, Steven Obua, Roland Zumkeller) Discrete and Computational Geometry

Global Optimization in Type Theory (Roland Zumkeller) PhD thesis

Formal Global Optimisation with Taylor Models (Roland Zumkeller) Lecture Notes in Computer Science

Formal Verification of Dynamic Real-Time State-Transition Systems Using Linear Logic (長谷部 浩二 , Jean-Pierre Jouannaud, Antoine Kremer, 岡田 光弘, Roland Zumkeller) Proceedings of Software Science Conference, Nagoya


Open Yale Courses
TSF Jazz
Les arrondissements de Paris
How to make mayonnaise
Persian Poetry
Persian-English dictionary by Franics Joseph Steingass
Digital Photography
New York Review of Books
London Review of Books
Aljazeera English
Cost of War since 2001
Hoogle - find Haskell functions by their type
Detexify - find LaTeX symbols by drawing them


Some photos taken on trips to Iran (April 2006) and to Israel/Palestine (December 2007).

My T'ai Chi master (in Paris).

شتر آهسته می رود، شب و روز.
The camel walks slowly, but by night and day.
(Persian proverb)

email: (first name).(last name)

Valid XHTML 1.0 Strict Valid CSS!