A revised version of this paper was provided December 16.
In this paper, we use properties of the Chern character from
K-theory to negative cyclic homology to prove a conjecture of
Weibel - asserting that the K-theory of a scheme vanishes in
degrees less then minus the dimension of the scheme -
for schemes essentially of finite type over a field of
characteristic 0.
This paper will appear in the Annals of Mathematics, perhaps in December, 2007.