diff -r 975c807661ca -r 4e816ca8b5e2 pnas/pnas.tex --- a/pnas/pnas.tex Wed Nov 17 15:48:20 2010 -0800 +++ b/pnas/pnas.tex Wed Nov 17 16:30:24 2010 -0800 @@ -284,9 +284,9 @@ to the standard $k$-ball $B^k$. \nn{maybe add that in addition we want functoriality} -By default our balls are oriented, +By default our balls are unoriented, but it is useful at times to vary this, -for example by considering unoriented or Spin balls. +for example by considering oriented or Spin balls. We can also consider more exotic structures, such as balls with a map to some target space, or equipped with $m$ independent vector fields. (The latter structure would model $n$-categories with less duality than we usually assume.)