Makar - Limanov ’ s conjecture on free subalgebras ∗
نویسنده
چکیده
It is proved that over every countable field K there is a nil algebra R such that the algebra obtained from R by extending the field K contains noncommutative free subalgebras of arbitrarily high rank. It is also shown that over every countable field K there is an algebra R without noncommutative free subalgebras of rank two such that the algebra obtained from R by extending the field K contains a noncommutative free subalgebra of rank two. This answers a question of Makar-Limanov [15]. Mathematics Subject Classification MSC2000: 16S10, 16N40, 16W50, 16U99
منابع مشابه
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