Relative Chern Characters for Nilpotent Ideals

which is defined only when I is nilpotent and Q ⊂ A. Goodwillie showed that (1.2) is an isomorphism whenever it is defined, and that it coincides with (1.1) when I = 0. Using this and a 5-Lemma argument, he deduced that (1.1) is an isomorphism for any nilpotent I. The question of whether ch∗ and ch ′ ∗ agree for general nilpotent ideals I was left open in [4], and announced without proof in [7, 11.4.11]. This paper answers the question, proving in Theorem 6.5.1 that