Vafa-Witten invariants for projective surfaces II: semistable case

Y Tanaka, RP Thomas - arXiv preprint arXiv:1702.08488, 2017 - arxiv.org
We propose a definition of Vafa-Witten invariants counting semistable Higgs pairs on a
polarised surface. We use virtual localisation applied to Mochizuki/Joyce-Song pairs. For …

Holomorphic anomaly equations and the Igusa cusp form conjecture

G Oberdieck, A Pixton - Inventiones mathematicae, 2018 - Springer
Let S be a K3 surface and let E be an elliptic curve. We solve the reduced Gromov–Witten
theory of the Calabi–Yau threefold S * ES× E for all curve classes which are primitive in the …

Holomorphic anomaly equations for the Hilbert scheme of points of a K3 surface

G Oberdieck - Geometry & Topology, 2024 - msp.org
We conjecture that the generating series of Gromov–Witten invariants of the Hilbert schemes
of n points on a K3 surface are quasi-Jacobi forms and satisfy a holomorphic anomaly …

Virtual counts on Quot schemes and the higher rank local DT/PT correspondence

SV Beentjes, AT Ricolfi - arXiv preprint arXiv:1811.09859, 2018 - arxiv.org
We show that the Quot scheme $\text {Quot} _ {\mathbf {A}^ 3}(\mathcal {O}^ r, n) $ admits a
symmetric obstruction theory, and we compute its virtual Euler characteristic. We extend the …

Multiple cover formulas for K3 geometries, wall-crossing, and Quot schemes

G Oberdieck - arXiv preprint arXiv:2111.11239, 2021 - arxiv.org
Let $ S $ be a K3 surface. We study the reduced Donaldson-Thomas theory of the cap
$(S\times\mathbb {P}^ 1)/S_ {\infty} $ by a second cosection argument. We obtain four main …

Quasimaps to moduli spaces of sheaves on a surface

D Nesterov - Forum of Mathematics, Sigma, 2024 - cambridge.org
In this article, we study quasimaps to moduli spaces of sheaves on a $ K3 $ surface S. We
construct a surjective cosection of the obstruction theory of moduli spaces of $\epsilon …

Sheaf counting on local K3 surfaces

D Maulik, RP Thomas - arXiv preprint arXiv:1806.02657, 2018 - arxiv.org
There are two natural ways to count stable pairs or Joyce-Song pairs on $ X=\mathrm
{K3}\times\mathbb C $; one via weighted Euler characteristic and the other by virtual …

A proof of the Donaldson–Thomas crepant resolution conjecture

SV Beentjes, J Calabrese, JV Rennemo - Inventiones mathematicae, 2022 - Springer
We prove the crepant resolution conjecture for Donaldson–Thomas invariants of hard
Lefschetz 3-Calabi–Yau (CY3) orbifolds, formulated by Bryan–Cadman–Young, interpreting …

Curve counting on elliptic Calabi–Yau threefolds via derived categories

G Oberdieck, J Shen - Journal of the European Mathematical Society, 2019 - ems.press
We prove the elliptic transformation law of Jacobi forms for the generating series of
Pandharipande–Thomas invariants of an elliptic Calabi–Yau threefold over a reduced class …

Stable pairs and Gopakumar-Vafa type invariants on holomorphic symplectic 4-folds

Y Cao, G Oberdieck, Y Toda - Advances in Mathematics, 2022 - Elsevier
As an analogy to Gopakumar-Vafa conjecture on Calabi-Yau 3-folds, Klemm-
Pandharipande defined Gopakumar-Vafa type invariants of a Calabi-Yau 4-fold X using …