Character sums and Ramsey properties of generalized Paley graphs.
Consider the families of curves and where A is a nonzero rational. Let and denote their respective Jacobian varieties. The torsion points of and are well known. We show that for any nonzero rational A the torsion subgroup of is a 2-group, and for A ≠ 4a⁴,-1728,-1259712 this subgroup is equal to (for a excluded values of A, with the possible exception of A = -1728, this group has a point of order 4). This is a variant of the corresponding results for (A ≠ 4) and . We also almost...