semifrustration

[captainhairdo]

So this weekend I proved a new result. Well, not new, but a new proof. My grad advisor had said that it was a tricky result and proof was not obvious, and I found a simple algebraic proof, so I was pretty happy. Then when searching the literature and web I found that it was already done. Crap. I think I would have been surprised if this proof hadn't been discovered since the result was established nearly a hundred years ago. Well, such is the life in math. But the whole thing has given me a new idea.

For anyone who cares, the result is Issai Schur's on that the Hadamard product of two positive matrices is also positive. The proof in question is the one on the bottom of this page which involves Kronecker products.