Comparison with Markman’s hyperholomorphic bundles

Determine whether the twisted hyperholomorphic vector bundle Q constructed from transverse Lagrangian fibrations is deformation equivalent along diagonal twistor lines to one of Markman’s vector bundles U^[n].

Background

The paper constructs a twisted hyperholomorphic vector bundle Q on a product of hyperkähler manifolds of K- or OG-type by convolving twisted Poincaré sheaves associated with two transverse Lagrangian fibrations.

Markman previously constructed hyperholomorphic bundles U[n] for products of hyperkähler manifolds of K-type. The authors explicitly leave unresolved whether their new construction yields bundles deformation equivalent to Markman’s bundles along diagonal twistor lines.

References

Is the twisted hyperholomorphic vector bundle Q deformation equivalent along diagonal twistor lines to one of the vector bundles U{[n]} considered by Markman in ?

Equivalences via twisted hyperholomorphic sheaves from transverse Lagrangian fibrations  (2608.13403 - Hartlieb et al., 13 Aug 2026) in Question immediately following Theorem 1.3, Section 1, Introduction