Abstract
Let R be a local Artin ring with maximal ideal m and residue class field of characteristic p > 0. We show that every finite flat group scheme over R is annihilated by its rank, whenever mp = pm = 0. This implies that any finite flat group scheme over an Artin ring the square of whose maximal ideal is zero, is annihilated by its rank.
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Schoof, R. Finite Flat Group Schemes over Local Artin Rings. Compositio Mathematica 128, 1–15 (2001). https://doi.org/10.1023/A:1017560215203
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DOI: https://doi.org/10.1023/A:1017560215203