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Related papers: Twistorial structures revisited

200 papers

We discuss the geometry of the c-map from projective special K\"ahler to quaternionic K\"ahler manifolds using the twist construction to provide a global approach to Hitchin's description. As found by Alexandrov et al. and Alekseevsky et…

Differential Geometry · Mathematics 2015-06-19 Oscar Macia , Andrew Swann

Biological networks are customarily described as structurally robust. This means that they often function extremely well under large forms of perturbations affecting both the concentrations and the kinetic parameters. In order to explain…

Optimization and Control · Mathematics 2026-02-20 M. Ali Al-Radhawi , David Angeli , Eduardo Sontag

We establish a correspondence between Pavlovian conditioning processes and fractals. The association strength at a training trial corresponds to a point in a disconnected set at a given iteration level. In this way, one can represent a…

Quantitative Methods · Quantitative Biology 2018-04-24 Gianluca Calcagni

We study the Penrose transform for the `quaternionic objects' whose twistor spaces are complex manifolds endowed with locally complete families of embedded Riemann spheres with positive normal bundles.

Differential Geometry · Mathematics 2015-03-26 Radu Pantilie

We show that on a surface locally every affine torsion-free connection is projectively equivalent to a Weyl connection. First, this is done using exterior differential system theory. Second, this is done by showing that the solutions of the…

Differential Geometry · Mathematics 2013-12-20 Thomas Mettler

We study differential forms invariant under a finite reflection group over a field of arbitrary characteristic. In particular, we prove an analogue of Saito's freeness criterion for invariant differential 1-forms. We also discuss how…

Representation Theory · Mathematics 2007-10-18 Julia Hartmann , Anne V. Shepler

The theory of slice regular functions of a quaternion variable is applied to the study of orthogonal complex structures on domains \Omega\ of R^4. When \Omega\ is a symmetric slice domain, the twistor transform of such a function is a…

Differential Geometry · Mathematics 2015-07-27 Graziano Gentili , Simon Salamon , Caterina Stoppato

The purpose of this article is to present the theory of higher order connections on vector bundles from a viewpoint inspired by projective differential geometry.

Differential Geometry · Mathematics 2009-08-12 Michael G. Eastwood

We study almost hypercomplex skew-Hermitian structures and almost quaternionic skew-Hermitian structures, as the geometric structures underlying $\mathsf{SO}^\ast(2n)$- and $\mathsf{SO}^\ast(2n)\mathsf{Sp}(1)$-structures, respectively. The…

Differential Geometry · Mathematics 2023-11-29 Ioannis Chrysikos , Jan Gregorovič , Henrik Winther

Given a special Kahler manifold M, we give a new, direct proof of the relationship between the quaternionic structure on its cotangent bundle and the variation of Hodge structures on the complexification of TM.

Mathematical Physics · Physics 2011-11-10 Claudio Bartocci , Igor Mencattini

This talk summarized work done recently to organize the steps for implementing TMD phenomenology in a way optimized for contexts where the extraction and interpretation of hadronic structures and nonperturbative effects is the primary…

High Energy Physics - Phenomenology · Physics 2024-08-15 Ted Rogers , Fatma Aslan , Mariaelena Boglione , J. Osvaldo Gonzalez-Hernandez , Tommaso Rainaldi , Andrea Simonelli

We describe various strengthenings of the concept of topological transitivity. Especially when one departs from the family of invertible systems, a number of interesting properties arise. We present the architecture of implications among…

Dynamical Systems · Mathematics 2016-01-22 Ethan Akin , Joseph Auslander , Anima Nagar

This is a study of the construction of particular regular sub-n-gons T in regular n-gons P using a special system of chords of P. In particular, some of these sub-n-gons have areas which are integer divisors of the area of the given n-gon…

History and Overview · Mathematics 2026-03-03 James M Parks

Connecting curves have been shown to organize the rotational structure of strange attractors in three-dimensional dynamical systems. We extend the description of connecting curves and their properties to higher dimensions within the special…

Chaotic Dynamics · Physics 2015-06-15 Greg Byrne , Juan Cebral , Robert Gilmore

This article is devoted to the investigation of wrap groups of connected fiber bundles over the fields of real $\bf R$, complex $\bf C$ numbers, the quaternion skew field $\bf H$ and the octonion algebra $\bf O$. Cohomologies of wrap groups…

Algebraic Topology · Mathematics 2010-03-16 S. V. Ludkovsky

We study the formulation of bond-orientational order in an arbitrary two dimensional geometry. We find that bond-orientational order is properly formulated within the framework of differential geometry with torsion. The torsion reflects the…

Statistical Mechanics · Physics 2009-10-31 Mark Bowick , Alex Travesset

Motivated by the rich geometry of conformal Riemannian manifolds and by the recent development of geometries modeled on homogeneous spaces $G/P$ with $G$ semisimple and $P$ parabolic, Weyl structures and preferred connections are introduced…

Differential Geometry · Mathematics 2007-05-23 Andreas Cap , Jan Slovak

Following T. Suwa, we study unfoldings of algebraic foliations and their relationship with families of foliations, making focus on those unfoldings related to trivial families. The results obtained in the study of unfoldings are then…

Algebraic Geometry · Mathematics 2021-02-09 Federico Quallbrunn

A consistent and intuitive description of the twist-4 corrections to the hadron structure functions is presented in a QCD-improved parton model using time-ordered perturbative theory, where the collinear singularities are naturally…

High Energy Physics - Phenomenology · Physics 2009-10-31 Wei Zhu , Hongwei Xiong , Jianhong Ruan

We analyze the twistor space structure of certain one-loop amplitudes in gauge theory. For some amplitudes, we find decompositions that make the twistor structure manifest; for others, we explore the twistor space structure by finding…

High Energy Physics - Theory · Physics 2010-04-07 Freddy Cachazo , Peter Svrcek , Edward Witten