bio | website | gilkalai.wordpress.com |
---|---|---|
location | Jerusalem | |
age | 59 | |
visits | member for | 5 years, 2 months |
seen | 40 mins ago | |
stats | profile views | 17,404 |
Professor of Mathematics at the Hebrew University of Jerusalem and at Yale University
Nov 23 |
comment |
Examples for Decomposition Theorem
To what extent does Lusztig's work rely on the decomposition theorem? |
Nov 23 |
comment |
Fundamental Examples
Here is a link for ADE classification: en.wikipedia.org/wiki/ADE_classification and here are links for the A-B-C-D-E-F-G root systems and finite Coxeter groups via Dynkin diagrams en.wikipedia.org/wiki/Root_system en.wikipedia.org/wiki/Coxeter%E2%80%93Dynkin_diagram |
Nov 23 |
comment |
Fundamental Examples
here is a link: en.wikipedia.org/wiki/Penrose_tiling |
Nov 23 |
comment |
Fundamental Examples
This answer is by Euclid mathoverflow.net/users/2033/euclid I just added the link and picture. |
Nov 23 |
revised |
Fundamental Examples
added 165 characters in body |
Nov 23 |
revised |
The Sylvester Gallai Theorem and Sections of Varieties with “Simple Topology”.
added 1 characters in body |
Nov 23 |
answered | Generalizations of Boolean posets/lattices |
Nov 22 |
awarded | Nice Answer |
Nov 22 |
revised |
Fundamental Examples
added the words - or few |
Nov 22 |
comment |
Fundamental Examples
How does it touches the Quaternions? |
Nov 22 |
answered | Fundamental Examples |
Nov 22 |
awarded | Nice Question |
Nov 22 |
comment |
Combinatorics of the Stasheff polytopes
Many thanks, Greg! |
Nov 22 |
revised |
The Sylvester Gallai Theorem and Sections of Varieties with “Simple Topology”.
added 1138 characters in body; edited tags; edited tags |
Nov 22 |
revised |
A “round” lattice with low kissing number?
typos corrected, link added |
Nov 22 |
revised |
A “round” lattice with low kissing number?
update |
Nov 22 |
comment |
Definition of “simplicial complex”
There are many interesting notions of complexes (and more general structures on spaces) from the point of view of combinatorics. A natural condition (which is satisfied even by regular CW complexes) is that the combinatorics of the cells determones the topology of the space described by the complex. (But some combinatorics can be done even if this condition is violated.) Simplicial complexes in the second definition has also the advantage that they can be embedded linearly (not just PW linearly) to Euclidean spaces. Also cubical complexes are interesting in combinatorics and topology. |
Nov 22 |
comment |
Combinatorics of the Stasheff polytopes
Greg, is this the original paper where the Hatcher-Thurston objects defined? A. Hatcher, On triangulations of surfaces, Topology Appl. 40 (1991), 189–194. Also can you describe the construction in a little more detail? |
Nov 22 |
comment |
Theorems for nothing (and the proofs for free)
Indeed this is a wonderful theorem. Why is it intuitive correct? From all the first year algebra theorems it was the one where I had no intuition whatsoever. |
Nov 22 |
revised |
The Sylvester Gallai Theorem and Sections of Varieties with “Simple Topology”.
added 184 characters in body |