Free modules over free algebras and free group algebras: The Schreier technique
نویسندگان
چکیده
منابع مشابه
Computing Generators of Free Modules over Orders in Group Algebras
Let E be a number field and G be a finite group. Let A be any OE-order of full rank in the group algebra E[G] and X be a (left) A-lattice. We give a necessary and sufficient condition for X to be free of given rank d over A. In the case that the Wedderburn decomposition E[G] ∼= ⊕χMχ is explicitly computable and each Mχ is in fact a matrix ring over a field, this leads to an algorithm that eithe...
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متن کاملComputing generators of free modules over orders in group algebras II
Let E be a number field and G a finite group. Let A be any OE-order of full rank in the group algebra E[G] and X a (left) A-lattice. In a previous article, we gave a necessary and sufficient condition for X to be free of given rank d over A. In the case that (i) the Wedderburn decomposition E[G] ∼= ⊕ χ Mχ is explicitly computable and (ii) each Mχ is in fact a matrix ring over a field, this led ...
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 1969
ISSN: 0002-9947
DOI: 10.1090/s0002-9947-1969-0249461-9