ترغب بنشر مسار تعليمي؟ اضغط هنا

A tropical analog of Descartes rule of signs

41   0   0.0 ( 0 )
 نشر من قبل Boris Shapiro
 تاريخ النشر 2015
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

We prove that for any degree d, there exist (families of) finite sequences a_0, a_1,..., a_d of positive numbers such that, for any real polynomial P of degree d, the number of its real roots is less than or equal to the number of the so-called essential tropical roots of the polynomial obtained from P by multiplication of its coefficients by a_0, a_1,... a_d respectively. In particular, for any real univariate polynomial P of degree d with non-vanishing constant term, we conjecture that one can take a_k = e^{-k^2}, k = 0, ... , d. The latter claim can be thought of as a tropical generalization of Descartess rule of signs. We settle this conjecture up to degree 4 as well as a weaker statement for arbitrary real polynomials. Additionally we describe an application of the latter conjecture to the classical Karlin problem on zero-diminishing sequences.

قيم البحث

اقرأ أيضاً

We give a Descartes-like bound on the number of positive solutions to a system of fewnomials that holds when its exponent vectors are not in convex position and a sign condition is satisfied. This was discovered while developing algorithms and softwa re for computing the Gale transform of a fewnomial system, which is our main goal. This software is a component of a package we are developing for Khovanskii-Rolle continuation, which is a numerical algorithm to compute the real solutions to a system of fewnomials.
We give a $q$-analog of middle convolution for linear $q$-difference equations with rational coefficients. In the differential case, middle convolution is defined by Katz, and he examined properties of middle convolution in detail. In this paper, we define a $q$-analog of middle convolution. Moreover, we show that it also can be expressed as a $q$-analog of Euler transformation. The $q$-middle convolution transforms Fuchsian type equation to Fuchsian type equation and preserves rigidity index of $q$-difference equations.
In this paper we introduce and study the class of d-ball packings arising from edge-scribable polytopes. We are able to generalize Apollonian disk packings and the well-known Descartes theorem in different settings and in higher dimensions. After int roducing the notion of Lorentzian curvature of a polytope we present an analogue of the Descartes theorem for all regular polytopes in any dimension. The latter yields to nice curvature relations which we use to construct integral Apollonian packings based on the Platonic solids. We show that there are integral Apollonian packings based on the tetrahedra, cube and dodecahedra containing the sequences of perfect squares. We also study the duality, unicity under Mobius transformations as well as generalizations of the Apollonian groups. We show that these groups are hyperbolic Coxeter groups admitting an explicit matrix representation. An unexpected invariant, that we call Mobius spectra, associated to Mobius unique polytopes is also discussed.
257 - Jens Hoppe 2021
Discrete minimal surface algebras and Yang Mills algebras may be related to (generalized) Kac Moody algebras, just as Membrane (matrix) models and the IKKT model - including a novel construction technique for minimal surfaces.
This is a foundational paper in tropical linear algebra, which is linear algebra over the min-plus semiring. We introduce and compare three natural definitions of the rank of a matrix, called the Barvinok rank, the Kapranov rank and the tropical rank . We demonstrate how these notions arise naturally in polyhedral and algebraic geometry, and we show that they differ in general. Realizability of matroids plays a crucial role here. Connections to optimization are also discussed.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا