Weights in a Serre-type conjecture for U(3)

Weights in a Serre-type conjecture for U(3)

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Florian Herzig, University of Toronto
Fine Hall 214

We consider a generalisation of Serre's conjecture for irreducible, conjugate self-dual Galois representations rho : $G_F -> GL_3(\bar F_p)$, where $F$ is an imaginary quadratic field in which $p$ splits. We previously gave a conjecture for the possible Serre weights of rho. If rho is modular and irreducible locally at p we establish this conjecture, modulo weights that are close to the boundary. Under our assumptions there are 9 predicted weights. This is joint work with Matthew Emerton and Toby Gee.