Lifting Lie Algebras over the Residue Field of a Discrete Valuation Ring
نویسنده
چکیده
Let R be a discrete valuation ring with maximal ideal πR and residue field k. We study obstructions to lifting a Lie algebra L over R/πR to one over R/πR. If L̄ is the Lie algebra over k obtained from reducing L then we show there exists a well-defined class in H(L̄, ad) which vanishes if and only if L lifts. Furthermore, if L lifts, the lifts are shown to be in one to one correspondence with H(L̄, ad).
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