8 papers
A criterion for parabolic vector bundles to admit a parabolic Lie algebroid connection
David Alfaya, Ashima Bansal, Indranil Biswas +1
Given a holomorphic Lie algebroid on a compact connected Riemann surface , we give a necessary and sufficient condition for a parabolic vector bundle on , with parab…
Singularity of cubic hypersurfaces and hyperplane sections of projectivized tangent bundle of projective space
Ashima Bansal, Supravat Sarkar, Shivam Vats
We show that the normal points of a cubic hypersurface in projective space have canonical singularities unless the hypersurface is an iterated cone over an elliptic curve. As an ap…
Lie algebroid connection and Harder-Narasimhan reduction
Ashima Bansal, Indranil Biswas, Pradip Kumar
Take a holomorphic Lie algebroid on a compact connected Riemann surface such that the anchor map is not surjective. Let be a parabolic subgroup of a complex…
Pullback and Direct Image of Parabolic Ample and Parabolic Nef Vector Bundles
Ashima Bansal, Indranil Biswas
We prove that under a finite surjective map of irreducible smooth complex projective curves, the pullback and direct image of a parabolic ample (respectively, parabolic nef) vector…
Automorphisms of punctual Hilbert schemes and symmetric powers of varieties
Ashima Bansal, Supravat Sarkar, Shivam Vats
We classify complex smooth projective surfaces whose punctual Hilbert scheme has a non-natural automorphism preserving the big diagonal. This completely answers a question raised b…
Isomorphisms and automorphisms of multiprojective bundles and symmetric powers of projective bundles
Ashima Bansal, Supravat Sarkar, Shivam Vats
We describe when two multiprojective bundles (fibre products of projective bundles over the same base) over projective spaces are isomorphic as abstract varieties. We also describe…