arXiv subjects

Saptarshi Dandapat

Publications and source records attributed to Saptarshi Dandapat.

2 recordsLinked to original sources

arXiv2026

Campana Rational Connectedness and Weak Approximation of Del Pezzo Orbifolds

We prove that a del Pezzo orbifold of degree less than 7, and del Pezzo orbifolds of higher degree with irreducible boundary are strongly Campana uniruled, and deduce that it is Campana rationally connected. This provides important non-toric examples in dimension two of a conjecture by Campana, in the form required by the weak approximation theorem, and yields weak approximation for Campana sections of Campana fibrations at all places whose general fibre is such an orbifold. In three appendices we classify the del Pezzo orbifolds of degree 6, 7 and 8 with irreducible boundary.

math.AG↗

arXiv2026

Classification of low degree del Pezzo orbifolds

In this paper we classify low degree del Pezzo orbifolds with irreducible boundaries. In order to achieve desired boundaries, we classify low degree curves on low degree del Pezzo surfaces. The notion of Campana orbifolds was introduced by Campana in 2004. A del Pezzo orbifold is a Campana orbifold whose underlying surface is a del Pezzo surface. The classification is elementary applications of adjunction formula, Riemann-Roch theorem, Hodge Index theorem and Kawamata-Viehweg vanishing theorem.

math.AG↗