Ela Sln(f[x]) Is Not Boundedly Generated by Elementary Matrices: Explicit Proof∗
نویسنده
چکیده
Using methods of higher algebraic K-theory, van der Kallen proved that SLn(F [x]) does not have bounded word length with respect to elementary matrices if the field F has infinite transcendence degree over its prime subfield. A short explicit proof of this result is exhibited by constructing a sequence of matrices with infinitely growing word length. This construction is also used to show that SLn(Z[x]) does not have bounded word length with respect to elementary matrices of “bounded degree”.
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