40 research outputs found
Derived equivalences induced by big cotilting modules
We prove that given a Grothendieck category G with a tilting object of finite
projective dimension, the induced triangle equivalence sends an injective
cogenerator of G to a big cotilting module. Moreover, every big cotilting
module can be constructed like that in an essentially unique way. We also prove
that the triangle equivalence is at the base of an equivalence of derivators,
which in turn is induced by a Quillen equivalence with respect to suitable
abelian model structures on the corresponding categories of complexes.Comment: 33 pages; version 2: more details added in Remark 1.11 and in the
proofs of Lemmas 1.17 and 4.4, discussion of well-known or inessential
results has been reduced (e.g. basics on model structures or the relation to
co-t-structures), references have been update
Generating the bounded derived category and perfect ghosts
We show, for a wide class of abelian categories relevant in representation
theory and algebraic geometry, that the bounded derived categories have no
non-trivial strongly finitely generated thick subcategories containing all
perfect complexes. In order to do so we prove a strong converse of the Ghost
Lemma for bounded derived categories.Comment: 15 pages; version 2: more details added and presentation improved,
reference list expanded and updated including references to examples
illustrating our result
On compactly generated torsion pairs and the classification of co-t-structures for commutative noetherian rings
We classify compactly generated co-t-structures on the derived category of a
commutative noetherian ring. In order to accomplish that, we develop a theory
for compactly generated Hom-orthogonal pairs (also known as torsion pairs in
the literature) in triangulated categories that resembles Bousfield
localization theory. Finally, we show that the category of perfect complexes
over a connected commutative noetherian ring admits only the trivial
co-t-structures and (de)suspensions of the canonical co-t-structure and use
this to describe all silting objects in the category.Comment: 34 pages. Version 2: minor corrections, references added and update