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702 Phillips Hall
Department of Mathematics
801 22nd St. NW
George Washington University
Washington, DC 20052

: 202-994-6235
Fax: 202-994-6760
Math Department: 202-994-6235
Email: robinson at gwu dot edu

Office Hours:
By appointment only.

Chair Tiling

This animation shows the tiling substitution producing the “chair” tiling. It is an example of a constant “size” substitution with a “coincidence”. As a result this tiling has discrete diffraction spectrum. See the paper “On the table and the chair”  Indag. Math 10, 1999.

Courses, etc. :

On leave until Spring 2020.




My research is on ergodic theory and dynamical systems, especially the application of these subjects to tilings, quasicrystals, and numeration. See my papers and old lectures (and other used items) for more details.

I am also interested in applications of mathematics to politics. My book (right) coauthored with Dan Ullman, recently cam out in its 2nd edition!


Deputy Chair, Mathematics
  Director of Graduate Studies (DGS), Mathematics
✤  Dean's Council, Colombian College of Arts and Science
✤ Faculty Senate Physical Facilities Committee