The Ghost Dimension of a Ring

نویسندگان

  • MARK HOVEY
  • KEIR LOCKRIDGE
چکیده

We introduce the concept of the ghost dimension gh. dim. R of a ring R. This is the longest nontrivial chain of maps in the derived category emanating from a perfect complex such that each map is zero on homology. We show that gh. dim. R ≤ w. dim. R, with equality if R is coherent or w. dim. R = 1.

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تاریخ انتشار 2008