Laurent Bartholdi
I'm a Professor at the Mathematical Institute of the GeorgAugust University of Göttingen. I am also the conservator of the models collection. Here is a map of Göttingen with important mathematical places.
 Search in the new catalogue of the mathematical library:
 News:
Model collection
65537gon.
Publications (HTML), Google Scholar and arXiv
 Curriculum vitae:
 In HTML or PDF format
.
I am currently interested in understanding fractal behaviour in
group theory and algebra, and its use for holomorphic dynamical
systems.
Selfsimilar, or fractal, objects abound in mathematics; depending
on context, they mean a space containing several almost disjoint
copies of itself as subspaces; a group containing the direct product
of copies of itself as a subgroup; or an algebra containing a matrix
algebra over itself as a subalgebra. The fractalness is
algebraically encoded via the collection of inclusion maps of these
subobjects in their common parent.
A selfsimilar group may be associated with any complex dynamical
system, and yields an extremely potent algebraic invariant of that
dynamical system up to isotopy and conjugation. I currently explore
more deeply the connection between complex dynamics and fractal
groups, and use it to extend the classification of degreetwo
polynomials (described by points in the Mandelbrot set) to
arbitrarydegree rational functions.
 Nerd score:

 Links:
 The FR GAPpackage, for manipulation of groups and semigroups generated by automata.
 The Float GAPpackage, for manipulation of real, complex, interval etc. floatingpoint numbers.
 Göttingen collection of mathematical models
 Slides
I received from
speakers in the conference "Trends and Directions in Conformal
Dynamics" in Oberwolfach, October 1721, 2008
 Windows
crashes in everyday life  a
commented photo gallery
 Movies
Movies illustrating the "twisted rabbit" paper in
progress with V. Nekrashevych.
 How I Rank in Hell
 My Images
 A movie I
made (hirez) of the Schreier graph of the GuptaSidki group,
in avi
and MPEG1 format.
 Bibliography (BibTeX) of papers I'm interested in,
in zip
and tar.gz format.
 LaTeX2e style file for sending notes
in LaTeX to the CRAS (Comptes Rendus de l'Académie des
Sciences de Paris), in zip
and tar.gz format (contains G. Perec's article
"Experimental... Cantatrix sopranica L." as a sample).