Comments on " Orbits of Automorphism Groups of Fields "
نویسنده
چکیده
Let R be a commutative k−algebra over a field k. Assume R is a Noetherian integral domain and |R| = ∞. The group of k−automorphisms of R,i.e., Autk(R) acts in a natural way on (R − k). We study the structure of R when orbit space (R−k)/Autk(R) is finite, and note that most of the results proved in [1, §2] hold in this case as well. We also give an elementary proof of [1,Theorem 1.1] in case k is finitely generated over its prime subfield.
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