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Related papers: Nonrational polytopes and fans in toric geometry

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This article discusses the concept of rational equivalence in tropical geometry (and replaces the older and imperfect version arXiv:0811.2860). We give the basic definitions in the context of tropical varieties without boundary points and…

Algebraic Geometry · Mathematics 2019-10-14 Lars Allermann , Simon Hampe , Johannes Rau

In dimension two, we reduce the classification problem for asymptotically log Fano pairs to the problem of determining generality conditions on certain blow-ups. In any dimension, we prove the rationality of the body of ample angles of an…

Algebraic Geometry · Mathematics 2024-11-20 Paolo Cascini , Jesus Martinez-Garcia , Yanir A. Rubinstein

We exhibit geometric conditions on a family of toric hypersurfaces under which the value of a canonical normal function at a point of maximal unipotent monodromy is irrational.

Algebraic Geometry · Mathematics 2020-06-16 Matt Kerr

In this review article we discuss some of the applications of noncommutative geometry in physics that are of recent interest, such as noncommutative many-body systems, noncommutative extension of Special Theory of Relativity kinematics,…

High Energy Physics - Theory · Physics 2009-11-19 Rabin Banerjee , Biswajit Chakraborty , Subir Ghosh , Pradip Mukherjee , Saurav Samanta

This paper explores the birational geometry of a general Horrocks-Mumford quintic threefold, describing the set of all minimal models up to marked isomorphism, the movable fan (the way in which the nef cones of all these models are arranged…

Algebraic Geometry · Mathematics 2007-05-23 M. J. Fryers

We treat the classical notion of convexity in the context of hard real analysis. Definitions of the concept are given in terms of defining functions and quadratic forms, and characterizations are provided of different concrete notions of…

Classical Analysis and ODEs · Mathematics 2009-09-01 Steven G. Krantz

This talk reviews some mathematical and physical ideas related to the notion of dimension. After a brief historical introduction, various modern constructions from fractal geometry, noncommutative geometry, and theoretical physics are…

Algebraic Geometry · Mathematics 2007-05-23 Yuri I. Manin

We give a brief introduction to tensor triangulated geometry, a brief introduction to various motivic categories, and then make some observations about the conjectural structure of the tensor triangulated spectrum of the Morel-Voevodsky…

Algebraic Geometry · Mathematics 2016-08-10 Shane Kelly

This paper studies Batyrev's notion of primitive collection. We use primitive collections to characterize the nef cone of a quasi-projective toric variety whose fan has convex support, a result stated without proof by Batyrev in the smooth…

Algebraic Geometry · Mathematics 2008-09-03 David A. Cox , Christine von Renesse

We define and solve the toric version of the symplectic ball packing problem, in the sense of listing all 2n-dimensional symplectic-toric manifolds which admit a perfect packing by balls embedded in a symplectic and torus equivariant…

Symplectic Geometry · Mathematics 2007-05-23 Alvaro Pelayo

We prove that a Poisson structure on a projective toric variety which is invariant by the torus action and whose symplectic leaves are the torus orbits is not exact. This is deduced from a geometric criterion for non-exactness of Poisson…

Differential Geometry · Mathematics 2022-09-07 David Martínez Torres , Marcelo Silva

Growth of the Hilbert-Poincar\"e series for the rational homology of the free loop space of a toric space is addressed. In case the toric space is a manifold, the structure of the fan dictates whether the Hilbert-Poincar\"e series has…

Algebraic Topology · Mathematics 2016-03-24 A. Bahri , M. Bendersky , S. Gitler , F. R. Cohen

We consider two natural Lagrangian intersection problems in the context of symplectic toric manifolds: displaceability of torus orbits and of a torus orbit with the real part of the toric manifold. Our remarks address the fact that one can…

Symplectic Geometry · Mathematics 2012-01-18 Miguel Abreu , Leonardo Macarini

Let X be a complex, Gorenstein, Q-factorial, toric Fano variety. We prove two conjectures on the maximal Picard number of X in terms of its dimension and its pseudo-index, and characterize the boundary cases. Equivalently, we determine the…

Algebraic Geometry · Mathematics 2007-05-23 C. Casagrande

A very general hypersurface of dimension $n$ and degree $d$ in complex projective space is rational if $d \leq 2$, but is expected to be irrational for all $n, d \geq 3$. Hypersurfaces in weighted projective space with degree small relative…

Algebraic Geometry · Mathematics 2024-11-20 Louis Esser

This is a survey of topological properties of open, complete nonpositively curved manifolds which may have infinite volume. Topics include topology of ends, restrictions on the fundamental group, as well as a review of known examples.

Differential Geometry · Mathematics 2014-08-05 Igor Belegradek

We develop an equivariant version of the formalism of intermediate Jacobian torsor obstructions, and apply it to conic bundles over rational surfaces, quadric surface bundles over $\mathbb P^1$, and Fano threefolds.

Algebraic Geometry · Mathematics 2025-03-20 Tudor Ciurca , Sho Tanimoto , Yuri Tschinkel

This is a survey of Rational Homotopy Theory, intended for a Mathematical Physics readership.

Algebraic Topology · Mathematics 2025-01-23 Alexander A. Voronov

This is a survey on algorithmic questions about combinatorial and geometric properties of convex polytopes. We give a list of 35 problems; for each the current state of knowledege on its theoretical complexity status is reported. The…

Combinatorics · Mathematics 2007-05-23 Volker Kaibel , Marc E. Pfetsch

We consider linear systems on toric varieties of any dimension, with invariant base points, giving a characterization of special linear systems. We then make a new conjecture for linear systems on rational surfaces.

Algebraic Geometry · Mathematics 2007-05-23 Antonio Laface , Luca Ugaglia