We discuss arithmetic in the Jacobian of a hyperelliptic curve C of genus g. The traditional approach is to fix a point P C and represent divisor classes in the form E - d(P) where E is effective and 0 d g. We propose a different representation which is balanced at infinity. The resulting arithmetic is more efficient than previous approaches when there are 2 points at infinity.
Steven D. Galbraith, Michael Harrison, David J. Mi