Smoothness, flatness and deformations of subalgebras
نویسندگان
چکیده
منابع مشابه
Unruffled Extensions and Flatness over Central Subalgebras
A condition on an affine central subalgebra Z of a noetherian algebra A of finite GelfandKirillov dimension, which we call here unruffledness, is shown to be equivalent in some circumstances to the flatness of A as a Z-module. Unruffledness was studied by Borho and Joseph in work on enveloping algebras of complex semisimple Lie algebras, and we discuss applications of our result to enveloping a...
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In this note we prove that any W 1,2 mapping u in the plane that minimizes an appropriate quasiconvex energy functional subject to the Jacobian constraint det∇u = 1 a.e., are necessarily Lipschitz. Furthermore we show that the minimizers corresponding to uniformly convex energy are affine and give an example of non-affine minimizers subject to affine boundary data corresponding to a convex ener...
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ژورنال
عنوان ژورنال: Journal of Pure and Applied Algebra
سال: 1999
ISSN: 0022-4049
DOI: 10.1016/s0022-4049(99)00072-9