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Galois Seminar

Thursday, September 27, 2018 - 10:30am

Pete Clark

University of Georgia

Location

University of Pennsylvania

DRL 4E19

Note unusual day, time, and room.

Are there more quadratic reciprocity laws? One can formulate
Legendre and Jacobi symbols in any PID and ask for a quadratic reciprocity
law. The two classic ones are in Z (Gauss-Jacobi) and in the polynomial
ring F_q[t] over a finite field of odd order (Dedekind-Kuhne). It turns out
that there is an especially low-hanging quadratic reciprocity law in the
polynomial ring R[t] over the real numbers. Moreover this law looks
strikingly similar in form to QR in F_q[t] and thus raises the question of
a common generalization. In this talk I will give a generalization to an
nth power reciprocity law in k[t], where k is a perfect field with
procyclic Galois group and containing a primitive nth root of unity.
Moreover I will argue that this is close to being the "natural class of
fields" for which there is a "nice reciprocity law" in k[t]. This is joint
work with Paul Pollack.