If you fix a prime , and consider the Galois action of the decomposition group on the (rational) -adic Tate module (here "rational" means tensored with ),
then (in a standard way, due to Deligne) you can convert this action into a representation
of the Weil--Deligne group, and so in particular of the Weil group. Restricting to the
inertia group, you get a representation of the inertia group , known as the inertial type . It is independent of . (The only reason to detour through the Weil--Deligne group is to deal with possibly infinite image of tame inertia; if the elliptic curve has potentially good reduction, then we can skip this step and just take the representation of on the -adic Tate module, which has finite image and is independent of .)
[Added: In the above, one should insist that . If , then one can also arrive at a Weil-Deligne representation, and hence
inertial type, which is the same as the one obtained as above for , but to do this one must use Fontaine's theory: one forms the of the rational -adic Tate module,
which then can be converted into a Weil--Deligne representation in a standard way,
and hence gives an inertial type.]
Now one can look at the deformation ring parameterizing lifts
of of which at are of inertial type and Hodge--Tate weights and . (See Kisin's recent
JAMS paper about potentially semi-stable deformation rings.)
[Added: Here ,
i.e. we are looking at -adic deformations of which are potentially semi-stable
at , and whose inertial type, computed via as in the above added remark,
is equal to . But note that, by the preceding discussion, these deformations do precisely capture the idea of lifts of having the same "reduction type" as
the original elliptic curve .]
Let's suppose that really does have potentially good reduction. Then Kisin's "moduli of finite flat group schemes" paper shows that any lift parameterized by is modular. This shows that for an appropriately chosen
.
One thing to note: unlike in the original Taylor--Wiles setting, from this statement one doesn't get quantitive information about adjoint Selmer groups, and one doesn't get any simple interpretation of what this theorem means on the integral level.
(In other words, Artinian-valued points of have no simple interpretation in terms of a ramification condition at ; this is related to the fact that the theory
of only applies rationally, i.e. to -representations, not integrally,
i.e. not to representations over or over Artin rings.)
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