Math Forum / Mathematics / Research / February 2010

Papers (1)-(6) continue the publication of AGT Volume 10 issue 1 and
papers (7)-(9) complete issue 1 of GT Volume 14.
Six papers have been published by Algebraic & Geometric Topology
(1) Algebraic & Geometric Topology 10 (2010) 87-136

Can anyone recommend a modern text, at a level suitable for an
undergraduate economics major, that describes the sort of textual
analysis that Mosteller and Wallace did of the Federalists papers in
the 1960's? (Given a text with two possible authors, and information

(Suggested by a Putnam problem).
A set X of real numbers is nowhere dense if every nonempty open
interval in R contains a nonempty open subinterval disjoint from X.
Let X and Y be countable nowhere dense sets of non-negative real

Can we associated to every closed pointed salient convex cone C that
is contained in a Banach space V
a hyperplane H
which intersects each ray of C exactly once?

I am interested in obtaining the factorization of f(z) = cos (z) - sin
(z). Thank you.

I am interested in the following problem.  If B is a symmetric matrix,
and A is antisymmetric, find a square matrix X so that
BX-XB = A.
I can see how to solve it by diagonalizing B (but I need the eigenvalues

I have recently come across the paper by John Baez entitled "Kostant
on E8" where he shows that the e8 algebra can be expressed as a direct
sum of 31 8-dimensional Cartan algebras.
Some time ago I have noticed that the same is true of g2, that is it

Dears,
Let A be a 27 X 36 matrix over the filed with 3 elements and
X1,...,X36 be columns of A.
If