A negative answer to a question of Bass

Abstract

We address Bass' question, on whether Kn(R) = Kn(R[t]) implies Kn(R) = Kn(R[t1, t2]). In a companion paper, we establish a positive answer to this question when R is of finite type over a field of infinite transcendence degree over the rationals. Here we provide an example of an isolated surface singularity over a number field for which the answer the Bass' question is "no" when n = 0. © c 2010 American Mathematical Society.