The fundamental form of an inseparable extension
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- by Murray Gerstenhaber PDF
- Trans. Amer. Math. Soc. 227 (1977), 165-184 Request permission
Abstract:
If K is a finite purely inseparable extension of a field k, then the symmetric multiderivations of K (symmetric maps $f:K \times \cdots \times K\;(n\;{\text {times}}) \to K$ which are derivations as functions of each single variable) form a ring under the symmetrized cup product. This ring contains an element $\Gamma (K/k)$ called the fundamental form of K over k, which is defined up to multiplication by a nonzero element of K and has the property that if B is any intermediate field between K and k, then $\Gamma (K/B)$ divides $\Gamma (K/k)$.References
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Additional Information
- © Copyright 1977 American Mathematical Society
- Journal: Trans. Amer. Math. Soc. 227 (1977), 165-184
- MSC: Primary 13B10
- DOI: https://doi.org/10.1090/S0002-9947-1977-0429861-9
- MathSciNet review: 0429861