Abstract
We show that a number of pullback diagrams appear naturally in the study of pre-ordered Grothendieck groups. The passage of projective modules from a ring R to a factor ring R/I turns out to be particularly good for a certain class of ideals, which we call almost trace ideals. We generalize to arbitrary rings a result by Goodearl concerning the lattice of the directed convex subgroups of K 0 (R). Finally, we show that a variant K 0 ′(I) of the Grothendieck group of I, introduced by Quillen, has an easy description in terms of projective modules when I is an almost trace ideal. © de Gruyter 2006.
Original language | English |
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Pages (from-to) | 365-389 |
Journal | Forum Mathematicum |
Volume | 18 |
DOIs | |
Publication status | Published - 5 Jan 2006 |