Universal deformations, rigidity, and Ihara’s cocycle
نویسندگان
چکیده
In [Iha86b], Ihara constructs a universal cocycle Gal ( Q/Q ) −→ Zp[[t0, t1, t∞]]/ ((t0 + 1)(t1 + 1)(t∞ + 1)− 1) arising from the action of Gal ( Q/Q ) on certain quotients of the Jacobians of the Fermat curves
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