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Related papers: On the Noether--Fano inequalities

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The goal of this work is to study geometric properties of geometrically irreducible subschemes on degenerations of Fano varieties (more generally, of separably rationally connected varieties). It is known that these geometrically…

Algebraic Geometry · Mathematics 2024-09-17 Santai Qu

This brief and opinionated essay evolved from my closing talk at the Tenth International Workshop on Neutrino Telescopes, held in Venice in March 2003. Portions were inspired by several excellent presentations at the Workshop. Other…

High Energy Physics - Phenomenology · Physics 2016-09-06 Sheldon Lee Glashow

This is a short communication in reference to the comments in (arXiv: 1605.05147) of our paper in Int. J. Mod. Phys. D 25, 1650051 (2016). We have tried to answer to the comments or criticism in the paper.

General Relativity and Quantum Cosmology · Physics 2017-02-01 Sourav Dutta , Subenoy Chakraborty

We find new lower bounds on the torsion orders of very general Fano hypersurfaces over (uncountable) fields of arbitrary characteristic. Our results imply that unirational parametrizations of most Fano hypersurfaces need to have enormously…

Algebraic Geometry · Mathematics 2021-03-03 Stefan Schreieder

In statistical inference problems, we wish to obtain lower bounds on the minimax risk, that is to bound the performance of any possible estimator. A standard technique to obtain risk lower bounds involves the use of Fano's inequality. In an…

Information Theory · Computer Science 2018-04-06 Ramji Venkataramanan , Oliver Johnson

The form of the coupling of the scalar field with gravity and the potential have been found by applying Noether theorem to two dimensional minisuperspaces in induced gravity model. It has been observed that though the forms thus obtained…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. K. Sanyal , B. Modak

In this paper, we investigate the newly developed $f(R,\mathbf{T}^2)$ theory ($R$ is the Ricci scalar and $\mathbf{T}^2=T_{\alpha\beta}T^{\alpha\beta},~T _{\alpha\beta}$ demonstrates the energy-momentum tensor) to explore some viable…

General Relativity and Quantum Cosmology · Physics 2021-03-10 M. Sharif , M. Zeeshan Gul

In this thesis, we study the one parameter point transformations which leave invariant the differential equations. In particular we study the Lie and the Noether point symmetries of second order differential equations. We establish a new…

General Relativity and Quantum Cosmology · Physics 2015-01-22 Andronikos Paliathanasis

We discuss an extended Teleparallel gravity models comprising functions of scalar invariants constructed by torsion, torsion Gauss-Bonnet and boundary terms. We adopt the Noether Symmetry Approach to select the functional forms, the first…

General Relativity and Quantum Cosmology · Physics 2019-05-22 Sebastian Bahamonde , Ugur Camci , Salvatore Capozziello

This paper is a sequel to [arXiv:2403.18389]. We investigate the rationality problem for $\mathbf{Q}$-Fano threefolds of Fano index $\ge 3$.

Algebraic Geometry · Mathematics 2026-01-22 Yuri Prokhorov

We survey some results on the nonrationality and birational rigidity of certain hypersurfaces of Fano type. The focus is on hypersurfaces of Fano index one, but hypersurfaces of higher index are also discussed.

Algebraic Geometry · Mathematics 2014-01-08 Tommaso de Fernex

Following the analysis we have presented in a previous paper (that we refer to as [I]), we describe a Noether theorem related to symmetries, with the associated reduction procedures, for classical dynamics within the Lagrangian and the…

Mathematical Physics · Physics 2022-01-05 giuseppe marmo , luca schiavone , alessandro zampini

We discuss non-minimally coupled cosmologies involving different geometric invariants. Specifically, actions containing a non-minimally coupled scalar field to gravity described, in turn, by curvature, torsion and Gauss--Bonnet scalars are…

General Relativity and Quantum Cosmology · Physics 2021-11-29 Francesco Bajardi , Salvatore Capozziello

In this Letter by utilizing the Noether symmetry approach in cosmology, we attempt to find the tachyon potential via the application of this kind of symmetry to a flat Friedmann-Robertson-Walker (FRW) metric. We reduce the system of…

General Physics · Physics 2011-09-01 Mubasher Jamil , F. M. Mahomed , D. Momeni

A representation of an arbitrary system of strict linear inequalities in R^n as a system of points is proposed. The representation is obtained by using a so-called polarity. Based on this representation an algorithm for constructing a…

Discrete Mathematics · Computer Science 2008-02-15 K. S. Kobylkin

An iterative Noether scheme, advocated by Deser, is used to introduce gauge invariant couplings to nonrelativistic matter with global symmetries related to usual charge conservation and dipole conservation recently discussed in fractonic…

High Energy Physics - Theory · Physics 2022-07-20 Rabin Banerjee

The fundamental property of Fano varieties with mild singularities is that they have a finite polyhedral Mori cone. Thus, it is very interesting to ask: What we can say about algebraic varieties with a finite polyhedral Mori cone? I give a…

Algebraic Geometry · Mathematics 2007-05-23 Viacheslav V. Nikulin

We solve several new sharp inequalities relating three quantities amongst the area, perimeter, inradius, circumradius, diameter, and minimal width of planar convex bodies. As a consequence, we narrow the missing gaps in each of the missing…

Metric Geometry · Mathematics 2023-09-15 Bernardo González Merino

Determining when the birational automorphism group of a Fano variety is finite is an interesting and difficult problem. The main technique for studying this problem is by the Noether-Fano method. This method has been effective in studying…

Algebraic Geometry · Mathematics 2022-05-20 David Stapleton , Nathan Chen

Recently, some authors have made a falsifiable claim that Noether gauge symmetry for F(R) theory of gravity coupled to a tachyon field enforces gauge to vanish and leads to F(R) \propto R^2, with a tachyon potential V(\phi) \propto…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-13 Nayem Sk. , Abhik Kumar Sanyal