Results 31 to 40 of about 12,524 (89)
Weakly special threefolds and nondensity of rational points
Abstract We verify part of a conjecture of Campana predicting that rational points on the weakly special nonspecial simply connected smooth projective threefolds constructed by Bogomolov–Tschinkel are not dense. To prove our result, we establish fundamental properties of moduli spaces of orbifold maps, and prove a dimension bound for such moduli spaces
Finn Bartsch +2 more
wiley +1 more source
C*-actions on rational homogeneous varieties and the associated birational maps
Given a birational map among projective varieties, it is known that there exists a variety Z with a one-dimensional torus action such that the birational map is induced from two geometric quotients of Z. We proceed in the opposite direction: given a smooth projective variety X with a one-dimensional torus action, one can define a birational map ...
openaire +1 more source
Taking limits in topological recursion
Abstract When does topological recursion applied to a family of spectral curves commute with taking limits? This problem is subtle, especially when the ramification structure of the spectral curve changes at the limit point. We provide sufficient (straightforward‐to‐use) conditions for checking when the commutation with limits holds, thereby closing a ...
Gaëtan Borot +4 more
wiley +1 more source
Rational surface maps with invariant meromorphic two forms [PDF]
We consider a rational map f:S->S of a complex projective surface together with an invariant meromorphic two form. Under a mild topological assumption on the map, we show that the zeroes of the invariant form can be eliminated by birational change of ...
Diller, Jeffrey, Lin, Jan-Li
core
Cyclic cubic points on higher genus curves
Abstract The distribution of degree d$d$ points on curves is well understood, especially for low degrees. We refine this study to include information on the Galois group in the simplest interesting case: d=3$d = 3$. For curves of genus at least 5, we show cubic points with Galois group C3$C_3$ arise from well‐structured morphisms, along with providing ...
James Rawson
wiley +1 more source
Parity of ranks of Jacobians of curves
Abstract We investigate Selmer groups of Jacobians of curves that admit an action of a non‐trivial group of automorphisms, and give applications to the study of the parity of Selmer ranks. Under the Shafarevich–Tate conjecture, we give an expression for the parity of the Mordell–Weil rank of an arbitrary Jacobian in terms of purely local invariants ...
Vladimir Dokchitser +3 more
wiley +1 more source
On the Rational Real Jacobian Conjecture
Jacobian conjectures (that nonsingular implies a global inverse) for rational everywhere defined maps of real n-space to itself are considered, with no requirement for a constant Jacobian determinant or a rational inverse.
Campbell, L. Andrew
core
Deformation invariance of rational pairs
Rational pairs, recently introduced by Koll\'ar and Kov\'acs, generalize rational singularities to pairs $(X,D)$. Here $X$ is a normal variety and $D$ is a reduced divisor on $X$.
Erickson, Lindsay
core
On some invariants of cubic fourfolds. [PDF]
Gounelas F, Kouvidakis A.
europepmc +1 more source

