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Related papers: Seshadri constants and the generation of jets

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We give a lower bound of the $\delta$-invariants of ample line bundles in terms of Seshadri constants. As applications, we prove the uniform K-stability of infinitely many families of Fano hypersurfaces of arbitrarily large index, as well…

Algebraic Geometry · Mathematics 2022-04-28 Hamid Abban , Ziquan Zhuang

I review recent progress in the theory of relativistic jet production. The presently favored mechanism is an electrodynamic one, in which charged plasma is accelerated by electric fields that are generated by a rotating magnetic field. The…

Astrophysics · Physics 2007-05-23 David L. Meier

We review various aspects of jet physics in the context of hadron colliders. We start by discussing the definitions and properties of jets and recent development in this area. We then consider the question of factorization for processes…

High Energy Physics - Phenomenology · Physics 2016-09-14 Sebastian Sapeta

Astrophysical jets are associated with the formation of young stars of all masses, stellar and massive black holes, and perhaps even with the formation of massive planets. Their role in the formation of planets, stars, and galaxies is…

Astrophysics · Physics 2008-08-21 Ralph E. Pudritz , Robi Banerjee , Rachid Ouyed

Jets are ubiquitous in the Universe and, as demonstrated in this volume, are seen from a large number of astrophysical objects. For a number of reasons, in particular their proximity and the abundant range of diagnostics to determine their…

Solar and Stellar Astrophysics · Physics 2021-05-05 T. P. Ray , J. Ferreira

The jet charge is an old observable that has proven uniquely useful for discrimination of jets initiated by different flavors of light quarks, for example. In this Letter, we propose an approach to understanding the jet charge by…

High Energy Physics - Phenomenology · Physics 2023-04-27 Zhong-Bo Kang , Andrew J. Larkoski , Jinghong Yang

Recurrent chromospheric fan-shaped jets highlight the highly dynamic nature of the solar atmosphere. They have been named as ''light walls'' or ''peacock jets'' in high-resolution observations. In this study, we examined the underlying…

Solar and Stellar Astrophysics · Physics 2025-04-28 Annu Bura , Tanmoy Samanta , Avijeet Prasad , Ronald L. Moore , Alphonse C. Sterling , Vasyl Yurchyshyn , Arun Surya

The phenomenology of jets associated with a variety of black hole systems is summarized, emphasizing the constraints imposed on their origin. Models of jet formation are reviewed, focusing in particular on recent ideas concerning MHD…

Astrophysics · Physics 2009-10-31 Annalisa Celotti , Roger D. Blandford

The stability of astrophysical jets in the linear regime is investigated by presenting the methodology to find the growth rates of the various instabilities. We perturb a cylindrical axisymmetric steady jet, linearize the relativistic ideal…

High Energy Astrophysical Phenomena · Physics 2023-08-31 Nektarios Vlahakis

Seshadri constants express the so called local positivity of a line bundle on a projective variety. They were introduced by Demailly. The original idea of using them towards a proof of the Fujita conjecture failed but they quickly became a…

Let $X$ be a surface and let $L$ be an ample line bundle on $X$. We first obtain a lower bound for the Seshadri constant $\varepsilon(X,L,r)$, when $r \ge 3$. We then assume that $X$ is a ruled surface and study Seshadri constants on $X$ in…

Algebraic Geometry · Mathematics 2017-01-25 Krishna Hanumanthu , Alapan Mukhopadhyay

Though widely observed to be emanating out from a variety of galactic and extra-galactic sources, the underlying physical mechanism behind the formation of the cosmic jets and outflows are wrapped around by the veil of mystery till date.…

Astrophysics · Physics 2007-05-23 Tapas K. Das

Given an etale quotient q:X->Y of smooth projective varieties we relate the simple Seshadri constant of a line bundle M on Y with the multiple Seshadri constant of q*M in the points of the fiber. We apply this method to compute the Seshadri…

Algebraic Geometry · Mathematics 2007-05-23 Luis Fuentes Garcia

A quantitative description of the qualitative feature of multi-hadron final states known as the "number of jets" is given by a sequence of infrared finite shape observables (jet discriminators) that: take continuous values between 0 and 1;…

High Energy Physics - Phenomenology · Physics 2009-10-31 Fyodor V. Tkachov

Protostellar jets are known to emit in a wide range of bands, from radio to IR to optical bands, and to date also about ten X-ray emitting jets have been detected, with a rate of discovery of about one per year. We aim at investigating the…

Solar and Stellar Astrophysics · Physics 2015-05-18 R. Bonito , S. Orlando , M. Miceli , J. Eislöffel , G. Peres , F. Favata

The production of jets is studied in collisions of virtual photons, specifically for applications at HERA. Photon flux factors are convoluted with matrix elements involving either direct or resolved photons and, for the latter, with parton…

High Energy Physics - Phenomenology · Physics 2007-05-23 Christer Friberg , Torbjörn Sjöstrand

We prove that an $n$-dimensional complex projective variety is isomorphic to $\mathbb{P}^n$ if the Seshadri constant of the anti-canonical divisor at some smooth point is greater than $n$. We also classify complex projective varieties with…

Algebraic Geometry · Mathematics 2018-10-17 Yuchen Liu , Ziquan Zhuang

Vertically banded zonal jets are frequently observed in weakly or non-rotating stratified turbulence, with the quasi-biennial oscillation in the equatorial stratosphere and the ocean's equatorial deep jets being two examples. Explaining the…

Fluid Dynamics · Physics 2018-12-26 Joseph G Fitzgerald , Brian F Farrell

Seshadri constants, introduced by Demailly, measure the local positivity of a nef divisor at a point. In this paper, we compute the Seshadri constants of the anticanonical divisors of Fano manifolds with coindex at most $3$ at a very…

Algebraic Geometry · Mathematics 2019-03-25 Jie Liu

In analogy to the relation between symplectic packings and symplectic blow ups we show that multiple point Seshadri constants on projective complex surfaces can be calculated as the supremum of radii of multiple K\"ahler ball embeddings.

Algebraic Geometry · Mathematics 2016-09-13 Thomas Eckl