Theoretical Statistics and Mathematics Unit, ISI Delhi

Positivity preserving Hadamard matrix functions

by Rajendra Bhatia and Ludwig Elsner

For every positive real number $p$ that lies between even integers $2(m-1)$ and $2m$ we demonstrate a matrix $A = [a_{ij}]$ of order $2 (m+1)$ such that $A$ is positive definite but the matrix with entries $|a_{ij}|^p$ is not.

isid/ms/2007/01 [fulltext]

Click here to return to Preprints Page