Căldăraru's twisted derived equivalence conjecture for K3 surfaces

About 23 years old · traced to

Let XX) and X′X' be algebraic K3 surfaces, and let α∈H2(X,OX∗)\alpha\in H^2(X,\mathcal O_X^*) and α′∈H2(X′,OX′∗)\alpha'\in H^2(X',\mathcal O_{X'}^*) be torsion classes. Define the twisted transcendental lattices by lifting these classes to H2(X,Q)H^2(X,\mathbb Q) and H2(X′,Q)H^2(X',\mathbb Q) and setting

T(X,α):=Ker⁡(α:T(X)→Q/Z),T(X,\alpha):=\operatorname{Ker}(\alpha:T(X)\to\mathbb Q/\mathbb Z),

and similarly for T(X′,α′)T(X',\alpha').

Căldăraru's conjecture. There exists an exact equivalence between the derived categories of twisted coherent sheaves

Db⁡(Coh⁡α(X))≃Db⁡(Coh⁡α′(X′))D^{\operatorname b}(\operatorname{Coh}_\alpha(X))\simeq D^{\operatorname b}(\operatorname{Coh}_{\alpha'}(X'))

if and only if there exists a Hodge isometry

T(X,α)≅T(X′,α′).T(X,\alpha)\cong T(X',\alpha').

This conjecture proposes a lattice-theoretic characterization of equivalence between derived categories of twisted coherent sheaves on algebraic K3 surfaces. The source notes that the analytic analogue had recently been established, while the algebraic statement was proposed by Căldăraru.

References

Primary source

Daniel Huybrechts, “Generalized Calabi-Yau structures, K3 surfaces, and B-fields”, arXiv:math/0306162 (2004).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.