My question is referred to the statement and proof of Prop. 2.4 of Diamond's
article "An extension of Wiles' Results", in Modular Forms and Fermat Last
Theorem, page 479.
More precisely: fix l and p two distinct primes, with l odd. Let sigma be an
irreducible, continuous, degree 2 representation of the absolute Galois group
Gp of Qp, with coefficients in k, an algebraic closure of the finite
field with l elements.
Proposition 2.4 states that if the restriction of sigma to the inertia
subgroup of Gp is irreducible and p is odd, then sigma is isomorphic to the
representation induced from a character of the Galois group of a quadratic
ramified extension M of Qp.
The proof given works if the restriction of sigma to the wild inertia of Gp is
reducible (I think there's a typo in the first line of the proof). What if
sigma is irreducible on wild inertia (and p is always odd)? It seems to me that this case is not covered in the proof of the Proposition, but maybe I'm not seeing something obvious.. If such a representation exists, it cannot be induced from a quadratic extension M as above, so how does it fit in the description given by the Proposition? Can one say something about such a representation (for example something about its projective image?).
Thanks
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