Subject: Wu class question
Date: Tue, 06 Jul 2004 16:27:44 -0400
From: "Nicholas J. Kuhn" <njk4x@cms.mail.virginia.edu>
To: dmd1@lehigh.edu

Here is a comment from my email adverse colleague, Bob Stong ...

The answer to the question below is yes. Reason:
(1) Under the hypothesis, v_i = 0 if i < 2^s is clear.
(2) `One knows' that if 2^s does not divide j, then v_j is in the ideal
generated by v_1, ..., v_{2^s-1}.  sketch proof: follows from fact that
if 2^s does not divide j, then, in the Steenrod algebra, Sq^j is in the
right ideal generated by Sq^{2^t}, t<s.

Subject: A question for the discussion list
Date: Wed, 23 Jun 2004 23:17:25 +0400 (MSD)
From: Podkorytov Semen <ssp@euclid.pdmi.ras.ru>
To: dmd1@lehigh.edu

 Let xi be a vector bundle with w_i(xi)=0 for 0<i<2^n.
 Is it true that v_i(xi)=0 unless i is divisible by 2^n?

 Here w_i are the Stiefel-Whitney classes, v_i the Wu classes
 (defined by w = Sq v, where w=w_0+w_1+..., v=v_0+v_1+v_2+...).