Results 21 to 30 of about 47 (47)
Rational points on 3‐folds with nef anti‐canonical class over finite fields
Proceedings of the London Mathematical Society, Volume 130, Issue 1, January 2025.Abstract We prove that a geometrically integral smooth projective 3‐fold X$X$ with nef anti‐canonical class and negative Kodaira dimension over a finite field Fq$\mathbb {F}_q$ of characteristic p>5$p>5$ and cardinality q=pe>19$q=p^e > 19$ has a rational point.
Fabio Bernasconi, Stefano Filipazzi
wiley +1 more source
On Riemannian 4‐manifolds and their twistor spaces: A moving frame approach
Mathematische Nachrichten, Volume 297, Issue 12, Page 4651-4670, December 2024.Abstract In this paper, we study the twistor space Z$Z$ of an oriented Riemannian 4‐manifold M$M$ using the moving frame approach, focusing, in particular, on the Einstein, non‐self‐dual setting. We prove that any general first‐order linear condition on the almost complex structures of Z$Z$ forces the underlying manifold M$M$ to be self‐dual, also ...
Giovanni Catino +2 more
wiley +1 more source
Galois invariants of finite abelian descent and Brauer sets
Bulletin of the London Mathematical Society, Volume 56, Issue 10, Page 3240-3256, October 2024.Abstract For a variety over a global field, one can consider subsets of the set of adelic points of the variety cut out by finite abelian descent or Brauer–Manin obstructions. Given a Galois extension of the ground field, one can consider similar sets over the extension and take Galois invariants.
Brendan Creutz +2 more
wiley +1 more source
On the birational geometry of conic bundles over the projective space
Mathematische Nachrichten, Volume 297, Issue 4, Page 1208-1220, April 2024.Abstract Let π:Z→Pn−1$\pi :Z\rightarrow \mathbb {P}^{n-1}$ be a general minimal n$n$‐fold conic bundle with a hypersurface BZ⊂Pn−1$B_Z\subset \mathbb {P}^{n-1}$ of degree d$d$ as discriminant. We prove that if d≥4n+1$d\ge 4n+1$, then −KZ$-K_Z$ is not pseudo‐effective, and that if d=4n$d = 4n$, then none of the integral multiples of −KZ$-K_{Z}$ is ...
Alex Massarenti, Massimiliano Mella
wiley +1 more source
Unimodal singularities and boundary divisors in the KSBA moduli of a class of Horikawa surfaces
Mathematische Nachrichten, Volume 297, Issue 2, Page 595-628, February 2024.Abstract Smooth minimal surfaces of general type with K2=1$K^2=1$, pg=2$p_g=2$, and q=0$q=0$ constitute a fundamental example in the geography of algebraic surfaces, and the 28‐dimensional moduli space M$\mathbf {M}$ of their canonical models admits a modular compactification M¯$\overline{\mathbf {M}}$ via the minimal model program.
Patricio Gallardo +3 more
wiley +1 more source
Octonionic Magical Supergravity, Niemeier Lattices, and Exceptional & Hilbert Modular Forms
Fortschritte der Physik, Volume 72, Issue 2, February 2024.Abstract The quantum degeneracies of Bogomolny‐Prasad‐Sommerfield (BPS) black holes of octonionic magical supergravity in five dimensions are studied. Quantum degeneracy is defined purely number theoretically as the number of distinct states in charge space with a given set of invariant labels.
Murat Günaydin, Abhiram Kidambi
wiley +1 more source
Moduli of polarised Enriques surfaces — Computational aspects
Journal of the London Mathematical Society, Volume 109, Issue 1, January 2024.Abstract Moduli spaces of (polarised) Enriques surfaces can be described as open subsets of modular varieties of orthogonal type. It was shown by Gritsenko and Hulek that there are, up to isomorphism, only finitely many different moduli spaces of polarised Enriques surfaces.
Mathieu Dutour Sikirić, Klaus Hulek
wiley +1 more source
Some of the next articles are maybe not open access.