We study Schlichting’s
-theory
groups of the Buchweitz–Orlov singularity category
of a quasiprojective
algebraic scheme
with applications to algebraic K-theory.
We prove for isolated quotient singularities over an algebraically closed field of characteristic
zero that
is finite
torsion, and that
.
One of the main applications is that algebraic varieties with isolated quotient
singularities satisfy rational Poincaré duality on the level of the Grothendieck
group; this allows computing the Grothendieck group of such varieties in terms of
their resolution of singularities. Other applications concern the Grothendieck group of
perfect complexes supported at a singular point and topological filtration on the
Grothendieck groups.
Keywords
$K\mkern-2mu$-theory of singular varieties, quotient
singularity, derived category, singularity category