Number Theory Seminar

For an elliptic curve E over a number field K, one consequence of the Birch and Swinnerton-Dyer conjecture is the parity conjecture: the global root number should match the parity of the Mordell-Weil rank. Its weaker but more approachable version is the p-parity conjecture for a fixed prime p: the global root number should match the parity of the Z_p-corank of the p-infinity Selmer group. After surveying what is known on the p-parity conjecture, we will discuss its proof in the case when E has a K-rational p-isogeny.