Oxidizing SuperYang-Mills from (N=4,d=4) to (N=1,d=10)

We introduce superspace generalizations of the transverse derivatives to rewrite the four-dimensional N=4 Yang-Mills theory into the fully ten-dimensional N=1 Yang-Mills in light-cone form. The explicit SuperPoincare algebra is constructed and invariance of the ten-dimensional action is proved.Comment: 15 page

Extraction of a_nn from pi- d -> n n gamma

I present a calculation of the pi- d -> n n gamma reaction to third order in chiral perturbation theory. The short-distance physics of this reaction can be constrained by relating it to several important low-energy weak reactions. The theoretical error in a_nn extracted from this reaction can thus be reduced by a factor larger than three to +-0.05 fm.Comment: 2 pages, 2 eps figures, uses ws-procs9x6.cls, summary of invited talk at Chiral Dynamics 2006, Sept. 18-22, Durham/Chapel Hill, NC, to be published in the proceeding

Asymptotic improvement of the Gilbert-Varshamov bound for linear codes

The Gilbert-Varshamov bound states that the maximum size A_2(n,d) of a binary code of length n and minimum distance d satisfies A_2(n,d) >= 2^n/V(n,d-1) where V(n,d) stands for the volume of a Hamming ball of radius d. Recently Jiang and Vardy showed that for binary non-linear codes this bound can be improved to A_2(n,d) >= cn2^n/V(n,d-1) for c a constant and d/n <= 0.499. In this paper we show that certain asymptotic families of linear binary [n,n/2] random double circulant codes satisfy the same improved Gilbert-Varshamov bound.Comment: Submitted to IEEE Transactions on Information Theor