Noncommutative Geometry Seminar

Hadamard matrices are n by n square matrices H with elements
from {-1,+1}  such that H H^t = n I_n, where t denotes matrix
transposition and I_n is  the n by n unit matrix. A necessary
condition for the existence of  Hadamard matrices is that
n = 1, n = 2, n = (0 mod 4). The sufficiency of  this condition
is the celebrated Hadamard matrix conjecture, which is open
since it was formulated by Jacques Hadamard in 1893.
We will discuss a  structured form of the Hadamard matrix conjecture,
that leads to various  different formulations of the conjecture.
Namely we will describe in  detail a Commutative Algebra
formulation and a Coding Theory formulation.