Mathematics talks by Francisco Santos

Some talks I've given:

• Recent progress on th diameter of polyhedra and simplicial complexes
  June 27, 2013, FPSAC 2013
  This is no longer about the counter-examples to the Hirsch conjecture, but about the more general question underlying it. It is in fact a "survey talk" reviewing several recent results by different people. Apart of FPSAC, the same talk was delivered one week earlier in SoCG 2013, in Rio de Janeiro.
• A counter-example to the Hirsch Conjecture
  September 22, 2011, DMV Jahrestagung 2011 Köln
  I have spoken about my counter-example to the Hirsch conjecture many times. This is the version delivered as invited speaker in the German DMV Annual Meeting of 2011. This version is addressed at a general mathematical audience. In my Hirsch page you can find versions for even more general audiences, or for more specific ones (discrete geometers). There is also a "director's cut" version delivered as a four hour minicourse in Davis, Seville, Döllnsee (Berlin) and Ellwangen.
• 50 years of the Hirsch Conjecture
  17 June 2009, Renyi Institute, Budapest, Algorithmic and Combinatorial Geometry
  This was a talk on things related to the Hirsch Conjecture from the time when I was working in my survey with Eddie Kim, and just before I found counter-examples to the bounded Hirsch Conjecture (see above).
  Essentially the same talk was given at an AMS Sectional meeting in San Francisco and at the 2009 Congress of the Royal Spanish Math Society in Oviedo.
  Sometimes the talk had as subtitle "with focus on partial counter-examples". In fact, the only novelyty in the talk (and in the survey) is a new look at the Klee-Walkup unbounded non-Hirsch polyhedron and the Mani-Walkup non-Hirsch sphere.
• The cinderella of math.
  Date: 8 june 2007. Place: Fundación Ramón Areces, Madrid
  In the International Symposium "The Frontiers of Mathematics".
  This talk elaborates on the following paragraph, by A. Björner and R. P. Stanley:

  The recent development of combinatorics is somewhat like a cinderella story. It used to be looked down on by "mainstream" mathematicians as being somehow less respectable than other areas, in spite of many services rendered to both pure and applied mathematics. Then along came the prince of computer science with its many mathematical problems and needs. And it was combinatorics that best fitted the glass slipper held out.

  You can get the PDF file (8.6 Mb) of all slides, or the slides synchronized with the actual audio of the talk, in mov (34 Mb) or mp4 (64 Mb) format.
  
  
• Triangulations of polytopes
  Date: 28 August 2006. Place: Palacio de Congresos, Madrid.
  In the International Congress of Mathematicians.
  A talk introducing some aspects of triangulations of polytopes and their relation to several areas of mathematics (computational geometry, topological combinatorics, algebraic geometry). Intended for general mathematical audiences. You can get the PDF file (~800K) of all slides. See also the paper
  
  
• Introducción a la Teoría de la Rigidez (Introduction to rigidity theory)
  Date: 25 July 2006 Place: El Escorial, Madrid.
  In the II Escuela de Educación Matemática Miguel de Guzmán".
  A talk in Spanish introducing rigidity theory. It owes a lot to the very nice booklet "Counting of Frameworks" by Jack Graver (Dolciani Mathematical Expositions, n. 25, Mathematical Association of America, 2001). You can get the PDF file (~1700K) of all slides.