样式: 排序: IF: - GO 导出 标记为已读
-
Coefficient bounds and second Hankel determinant for a subclass of symmetric bi-starlike functions involving Euler polynomials Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-03-01 H.M. Srivastava, Timilehin Gideon Shaba, Musthafa Ibrahim, Fairouz Tchier, Bilal Khan
Various operators of fractional calculus, as well as their quantum (or -) extensions have been used widely and successfully in the study of the Taylor-Maclaurin coefficient estimation problems for many different families of normalized analytic, univalent and bi-univalent functions in Geometric Function Theory of Complex Analysis. On the other hand, Numerous writers have extensively employed orthogonal
-
Iterates of differential operators of Shubin type in anisotropic Roumieu Gelfand-Shilov spaces Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-02-28 M'Hamed Bensaid, Rachid Chaili
The purpose of this work is to show the iterate property for globally elliptic differential operators with polynomial coefficients (called Shubin operators), in the anisotropic Roumieu Gelfand-Shilov spaces . As a consequence we obtain a result of regularity of solutions of differential equations in these spaces.
-
Darboux theory of integrability on the Clifford n-dimensional torus Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-02-28 Jaume Llibre, Claudia Valls
For the polynomial vector fields on a Clifford -dimensional torus, we develop a Darboux theory of integrability. Moreover, we study the optimal maximum number of invariant meridians in terms of the degree of the polynomial vector field.
-
B-essential spectra of operators matrix block 3 × 3 applied to a radiative transfer equations in a channel Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-02-23 Faiçal Abdmouleh, Aymen Bahloul, Ines Walha
The aim of this paper is to study the stability of some B-essential spectra for closed linear operators in a Banach space under finite rank perturbations and to provide a characterization of specific B-essential spectra associated with a unbounded operator matrix defined over its maximal domain. As an application, grounded in this novel investigation, we present the diffusion problem of radiative transfer
-
Schatten class Hankel operators on weighted Bergman spaces induced by regular weights Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-02-20 Hamzeh Keshavarzi, Fanglei Wu
In this paper, for , we provide several descriptions of Schatten -class Hankel operators and on the weighted Bergman space , in terms of a certain global and local mean oscillation of the symbol , provided is in a class of regular weights. The approaches applied to rely on several classical methods, and simultaneously rely on a novel but more convenient construction associated with the atomic decomposition
-
Well-posedness and Ulam-Hyers stability of Hilfer fractional differential equations of order (1,2] with nonlocal boundary conditions Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-02-15 Kanika Dhawan, Ramesh Kumar Vats, Ankit Kumar Nain, Anurag Shukla
In this paper, the authors have proposed the qualitative properties for the solution of the Hilfer implicit fractional differential equations (HIFDE) of order involving nonlocal boundary conditions using fixed point theory. By imposing the growth conditions on a non-linear function the sufficient condition existence of a solution for the assumed problem is given by using Schaefer's fixed point theorem
-
Multiplicity and concentration properties for (p,q)-Kirchhoff non-autonomous problems with Choquard nonlinearity Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-02-09 Jiabin Zuo, Weiqiang Zhang, Vicenţiu D. Rădulescu
In this paper, we study the following -Kirchhoff problem with Choquard nonlinearity: where ε is a small positive parameter, are positive constants, , , with is the -Laplacian, the potential is continuous, , , is a continuous nonlinearity, and is the primitive of . The main result in this paper establishes multiplicity and concentration properties of positive solutions under weaker hypotheses. The proofs
-
Higher-order heat equation and the Gelfand-Dickey hierarchy Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-02-08 P, l, a, m, e, n, , I, l, i, e, v
In this paper we analyze the heat kernel of the equation , where is an -th order differential operator and the ± sign on the right-hand side is chosen appropriately. Using formal pseudo-differential operators, we derive an explicit formula for Hadamard's coefficients in the expansion of the heat kernel in terms of the resolvent of . Combining this formula with soliton techniques and Sato's Grassmannian
-
Orthogonal and symplectic parabolic connections and stack of roots Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-02-07 Sujoy Chakraborty, Souradeep Majumder
Let be an effective divisor on a smooth projective variety over an algebraically closed field of characteristic 0. We show that there is a one-to-one correspondence between the class of orthogonal (respectively, symplectic) parabolic vector bundles on with parabolic structure along and having rational weights and the class of orthogonal (respectively, symplectic) vector bundles on certain root stacks
-
Generalized Deligne–Hitchin twistor spaces: Construction and properties Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-02-06 Zhi Hu, Pengfei Huang, Runhong Zong
In this paper, we generalize the construction of Deligne–Hitchin twistor space by gluing two certain Hodge moduli spaces. We investigate some properties of such generalized Deligne–Hitchin twistor space as a complex analytic manifold. More precisely, we show it admits holomorphic sections whose normal bundle contains a semistable subbundle with positive degree and whose energy is semi-negative, and
-
Non-autonomous fractional Cauchy problems with almost sectorial operators Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-02-01 Jia Wei He, Yong Zhou
In this paper, we study a class of non-autonomous fractional Cauchy problems with the almost sectorial operators. We consider the time fractional derivative in the sense of Caputo type. First, we construct two operator families by means of Mittag-Leffler functions, which will be useful to both determine the structure of solution operator families and prove existence results. Moreover, we establish
-
Multiple sign-changing solutions for superlinear (p,q)-equations in symmetrical expanding domains Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-01-16 Wulong Liu, Guowei Dai, Patrick Winkert
In this paper we study quasilinear elliptic equations defined on symmetrical expanding domains driven by the -Laplacian and with a superlinear right-hand side. Based on the Lusternik-Schnirelmann category we prove the existence of at least pairs of odd weak solutions with precisely two nodal domains, where stands for the genus.
-
Approximate controllability of third order dispersion systems Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-01-10 Pooja Gautam, Anurag Shukla, M. Johnson, V. Vijayakumar
The current paper focuses on the approximate controllability of Volterra-Fredholm type integrodifferential third order dispersion system. The Banach fixed point theorem and semigroup operator are used to obtain the existence and uniqueness of mild solutions to the considered system. In order to examine the approximate controllability results, a different approach is used, namely, the sequential method
-
Difference of composition-differentiation operators from Hardy spaces to weighted Bergman spaces via harmonic analysis Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-01-08 Yecheng Shi, Songxiao Li
In this paper, the boundedness and compactness of the difference of composition-differentiation operators acting from Hardy spaces to weighted Bergman spaces are completely characterized for all .
-
Global dynamics of 3D cooperative Lotka-Volterra system with the identical intrinsic growth rate Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-01-06 Fengli Liang, Jifa Jiang, Xiang Zhang
In this paper, we complete the classification on global topological structures of the three-dimensional cooperative Lotka-Volterra system with the identical intrinsic growth rate inside the Poincaré compactification of the positive octant of . Precisely, with the help of the replicator equations it is proved that this kind of system can have exactly 8 topologically different phase portraits. As a consequence
-
-
On logarithmic coefficients for classes of analytic functions associated with convex functions Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-01-05 Vasudevarao Allu, Navneet Lal Sharma
Let denote the class of analytic and univalent functions in the unit disk of the form . For , the logarithmic coefficients defined by . In 1971, Milin proposed a system of inequalities for the logarithmic coefficients of . This is known as the Milin conjecture and implies the Robertson conjecture which implies the Bieberbach conjecture for the class . Recently, the other interesting inequalities involving
-
Boundedness of higher order commutators of Hardy operators on grand Herz-Morrey spaces Bull. des Sci. Math. (IF 1.3) Pub Date : 2024-01-02 Babar Sultan, Mehvish Sultan
Our aim in this paper is to find the boundedness of the higher order commutators of the Hardy operators on grand variable Herz-Morrey spaces by applying some properties of variable exponent.
-
Some sharp bounds of the third-order Hankel determinant for the inverses of the Ozaki type close-to-convex functions Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-12-22 H.M. Srivastava, Biswajit Rath, K. Sanjay Kumar, D. Vamshee Krishna
The main object of this article is to present the sharp bounds of the third-order Hankel determinant for functions in a subclass of normalized analytic functions in the open unit disk , which are the inverses of the class of Ozaki type close-to-convex functions. Several earlier developments, which are related to our main results, are also described.
-
Stability of linear operators in locally convex cones Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-12-21 Ismail Nikoufar, Asghar Ranjbari
The theory of locally convex cones generalizes locally convex topological vector spaces and provides many different examples and applications than locally convex vector spaces. The stability problem in the sense of Ulam has not yet received any attention in the theory of locally convex cones. Therefore, in this paper, we introduce the stability problem in locally convex cones and provide the stability
-
Factorization of holomorphic matrices and Kazhdan's property (T) Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-12-12 Gaofeng Huang, Frank Kutzschebauch, Josua Schott
In this article we deduce some algebraic properties for the group Sp2n(O(X)) of holomorphic symplectic matrices on a Stein space X: holomorphic factorization, exponential factorization, and Kazhdan's property (T). In holomorphic factorization we combine a recent result of the third author and K-theory tools to give explicit bounds for the case when X is one-dimensional or two-dimensional. Next we use
-
Double homoclinic bifurcations by perturbing a class of cubic Z2-equivariant polynomial systems with nilpotent singular points Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-12-12 Yanqin Xiong, Jianqiang Hu
This paper focuses on the study of the limit cycle bifurcation of a general cubic Z2-equivariant Hamiltonian differential system with two nilpotent singular points. Initially, the necessary and sufficient conditions for the occurrence of two nilpotent singularities are provided in the unperturbed system, along with a complete description of all possible phase portraits on the plane. Subsequently, using
-
Some results on four-manifolds with nonnegative biorthogonal curvature Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-12-13 Ze-Jiu Wu, Hai-Ping Fu, Peng Fu
Let (M,g) be a 4-dimensional compact oriented Riemannian manifold with nonnegative biorthogonal curvature and W− be the anti-self-dual component of the Weyl curvature tensor W. If M has constant scalar curvature and |W−| of M is constant, or if M has harmonic Weyl tensor and detW− or |W−| of M is constant, then we give two classification theorems for M. As two applications, a 4-dimensional compact
-
On the periodic and antiperiodic aspects of the Floquet normal form Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-12-12 Douglas D. Novaes, Pedro C.C.R. Pereira
Floquet's Theorem is a celebrated result in the theory of ordinary differential equations. Essentially, the theorem states that, when studying a linear differential system with T-periodic coefficients, we can apply a, possibly complex, T-periodic change of variables that transforms it into a linear system with constant coefficients. In this paper, we explore further the question of the nature of this
-
Réductions d'un système bidimensionnel de sine-Gordon à la sixième équation de Painlevé Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-12-11 Robert Conte, A. Michel Grundland
Nous établissons toutes les réductions du système de deux équations couplées de sine-Gordon introduit par Konopelchenko et Rogers à des équations différentielles ordinaires. Ces réductions sont toutes des dégénérescences d'une réduction maîtresse à une équation jugée par Chazy “curieuse en raison de [son] élégance”, transformée algébrique de la sixième équation de Painlevé la plus générale.
-
On inclusion relations between weighted spaces of entire functions Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-12-06 Gerhard Schindl
We characterize the inclusions of weighted classes of entire functions in terms of the defining weights resp. weight systems. First we treat weights defined in terms of a so-called associated weight function where the weight(system) is based on a given sequence. The abstract weight function case is then reduced to the weight sequence setting by using the so-called associated weight sequence. As an
-
Quasilinear double phase problems with parameter dependent performance on the whole space Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-12-01 Bin Ge, Wen-Shuo Yuan
This paper concerns with a class of double phase problem depending of one real parameter on the whole space. Under some appropriate assumptions, we obtain the existence of at least two solutions for the considered problem, which extend and complement previously known results in the literature.
-
Sharp decay estimate for solutions of general Choquard equations Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-11-30 Xu Miao, Junfang Zhao, Changmu Chu
Consider the general Choquard equation{Δpu+(∫RN|u(y)|pα⁎|x−y|αdy)|u|pα⁎−2u=0,inRN,u∈D1,p(RN), where 1
-
Positive periodic solutions of third-order neutral differential equations with delayed derivative terms Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-11-22 Shengbin Yang, Yongxiang Li
By applying fixed point index theory on cones, the existence results of positive 2π-periodic solutions are obtained for the third-order neutral differential equation with delayed derivative terms in nonlinearity(x(t)−cx(t−δ))‴+a(t)x(t)=f(t,x(t),x(t−τ0),x′(t−τ1),x″(t−τ2)),t∈R under the condition that the nonlinear term f satisfies superlinear or sublinear growth, where constants δ>0,|c|<1, a:R→(0,+∞)
-
Characterization of Lipschitz normally embedded complex curves Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-11-22 André Costa, Vincent Grandjean, Maria Michalska
The main result of the paper states that a connected complex affine algebraic curve is LNE in Cn if and only if its germ at any singular point is a finite union of non-singular complex curve germs which are pairwise transverse, and its projective closure is in general position with the hyperplane at infinity. To this aim, we completely characterize complex analytic curves of a compact complex manifold
-
-
A note on modified J-flow with the Calabi ansatz Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-11-10 P. Sivaram
We study the modified J-flow introduced in [15], particularly the singularities of the flow using the Calabi symmetry. In [20], on toric manifolds the convergence of modified J-flow to the smooth solution was proven under the assumption of positivity of certain intersection numbers. In the case of the Calabi ansatz we show that if some of those intersection numbers are not positive, then the modified
-
Certified Severi dimensions for hyperelliptic and supersymmetric cusps Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-11-10 Ethan Cotterill, Vinícius Lima, Renato Vidal Martins, Alexandre Reis
In a previous paper, the first three authors formulated a precise conjecture about the dimension of the generalized Severi variety Md,g;S,kn of degree-d holomorphic maps P1→Pn whose images' singularities are singleton cusps with value semigroups S and ramification profiles k. In this paper, we prove that an adjusted form of the conjecture holds for generic profiles k associated with two distinguished
-
On a-fold products ideals of hyperplane arrangements Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-10-27 Ricardo Burity
Given Σ⊂R:=K[x1,…,xk], where K is a field of characteristic 0, any finite collection of linear forms defining a hyperplane arrangement in Pk−1 and any 1≤a≤|Σ| satisfying |Σ|−a≥k, we prove that the ideal generated by all a-fold products of Σ, denoted by Ia(Σ), is of fiber type. Moreover, we verify a conjecture of Mantero, Miranda-Neto and Nagel on symbolic powers for the class of ideals generated by
-
Stability of Syzygy bundles corresponding to stable vector bundles on algebraic surfaces Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-10-18 Suratno Basu, Sarbeswar Pal
Let (X,H) be a polarized smooth projective algebraic surface and E is globally generated, stable vector bundle on X. Then the Syzygy bundle ME associated to it is defined as the kernel bundle corresponding to the evaluation map. In this article we will study the stability property of ME with respect to H.
-
Local/global existence analysis of fractional wave equations with exponential nonlinearity Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-10-18 Jia Wei He, Yong Zhou
In this paper, we concern with an exponential nonlinearity for a fractional wave equation in the whole space, we establish the local existence of solutions in a dense subspace of the Orlicz classification. Moreover, we obtain the global existence of solutions for small initial data in lower dimension 1≤d≤3. Our proofs base on the analyticity of Mittag-Leffler functions, the framework of prior estimates
-
-
Some existence and uniqueness results for a class of proportional Liouville-Caputo fractional stochastic differential equations Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-10-13 Abdellatif Ben Makhlouf, Lassaad Mchiri, Hari Mohan Srivastava
This paper is devoted to a systematic discussion of the existence and uniqueness of solution of a family of proportional Liouville-Caputo fractional stochastic differential equations by applying the Banach fixed point technique. We investigate the theory of the Ulam-Hyers-Rassias stability with respect to (ε,θ(ϑ)) of proportional Liouville-Caputo fractional stochastic differential equations by making
-
Evolution systems of probability measures for nonautonomous Klein-Gordon Itô equations on ZN Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-10-13 Renhai Wang, Erkan Nane, Nguyen Huy Tuan
Invariant probability measures of time-homogeneous transition semigroups for autonomous stochastic ODEs/PDEs/lattice systems have been widely discussed in the literature. In this work we investigate evolution systems of probability measures of time inhomogeneous transition operators for a class of nonautonomous Klein-Gordon Itô equation defined on an integer set ZN. The existence, periodicity, pointwise
-
On the properties of invariant functions Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-10-13 Zhi-Hong Sun
If f(x,y) is a real function satisfying y>0 and ∑r=0n−1f(x+ry,ny)=f(x,y) for n=1,2,3,…, we say that f(x,y) is an invariant function. Many special functions including Bernoulli polynomials, Gamma function and Hurwitz zeta function are related to invariant functions. In this paper we systematically investigate the properties of invariant functions.
-
On k-rotundity and k-uniform rotundity in direct sums of normed spaces Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-10-13 M. Veena Sangeetha
A real normed linear space X is k-rotund if and only if for any linearly independent x1,…,xk+1∈X, ‖x1+⋯+xk+1‖<‖x1‖+⋯+‖xk+1‖. We show that X is k-uniformly rotund if and only if the set {∑i=1k+1‖xi‖−‖∑i=1k+1xi‖:x1,…,xk+1∈BX,V(x1,…,xk+1,0)≥ϵ} is bounded below by a positive number for every positive ϵ. Using these characterizations of k-rotundity and k-uniform rotundity, we obtain necessary and sufficient
-
Well posedness of second-order non-instantaneous impulsive fractional neutral stochastic differential equations Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-10-13 K. Dhanalakshmi, P. Balasubramaniam
In this manuscript, the authors established existence, uniqueness and stability results for the second-order non-instantaneous impulsive fractional neutral stochastic differential equations (NIIFNSDEs). At first, existence and uniqueness results are obtained by using Caputo fractional derivative (fractional calculus), stochastic technique and fixed point approach with appropriate hypotheses on non-linear
-
Exceptional values of entire functions of finite order in one of the variables Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-10-11 Alvaro Bustinduy
Let F(z,w) be a holomorphic function in Cn×C of finite order in w with n≥2. Let Ω be the set of points z∈Cn where F(z,w) is a non-constant function omitting a value π(z). Near a finite accumulation point z0 of Ω, we prove in the main result (Theorem 1) that Ω is a local analytic set and π(z) is holomorphic, and show the existence of a proper globally analytic set Δ of Cn such that either Ω⊂Δ or Ω=Cn∖Δ
-
Existence of higher extremal Kähler metrics on a minimal ruled surface Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-10-11 Rajas Sandeep Sompurkar
In this paper we prove that on a special type of minimal ruled surface, which is an example of a ‘pseudo-Hirzebruch surface’, every Kähler class admits a certain kind of ‘higher extremal Kähler metric’, which is a Kähler metric whose corresponding top Chern form and volume form satisfy a nice equation motivated by analogy with the equation characterizing an extremal Kähler metric. From an already proven
-
Global smooth solutions for triangular reaction-cross diffusion systems Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-10-10 Jessica Guerand, Angeliki Menegaki, Ariane Trescases
For a class of reaction cross-diffusion systems of two equations with a cross-diffusion term in the first equation and with self-diffusion terms, we prove that the unique local smooth solution given by Amann theorem is actually global. This class of systems arises in Population dynamics, and extends the triangular Shigesada-Kawasaki-Teramoto system when general power-laws growth are considered in the
-
On almost stable linear Weingarten hypersurfaces Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-10-10 Julien Roth, Abhitosh Upadhyay
We prove that generalized linear Weingarten hypersurfaces of the Euclidean space which are almost stable for the associated stability problem are geodesic spheres.
-
Quasi-monotone convergence of plurisubharmonic functions Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-09-25 Vincent Guedj, Antonio Trusiani
The complex Monge-Ampère operator has been defined for locally bounded plurisubharmonic functions by Bedford-Taylor in the 80's. This definition has been extended to compact complex manifolds, and to various classes of mildly unbounded quasi-plurisubharmonic functions by various authors. As this operator is not continuous for the L1-topology, several stronger topologies have been introduced over the
-
Toeplitz operators on the weighted Bergman spaces of quotient domains Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-09-21 Gargi Ghosh, E.K. Narayanan
Let G be a finite pseudoreflection group and Ω⊆Cd be a bounded domain which is a G-space. We establish identities involving Toeplitz operators on the weighted Bergman spaces of Ω and Ω/G using invariant theory and representation theory of G. This, in turn, provides techniques to study algebraic properties of Toeplitz operators on the weighted Bergman space on Ω/G. We specialize on the generalized zero-product
-
Three families of q-supercongruences from a quadratic transformation of Rahman Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-09-18 Victor J.W. Guo
We present three families of q-supercongruences modulo the square and cube of a cyclotomic polynomial from a quadratic transformation by Rahman. In particular, as a limiting case we obtain the following supercongruence: for 0
-
Geometry of uniqueness varieties for a three-point Pick problem in D3 Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-09-14 Krzysztof Maciaszek
Motivated by recent progress in research on extending holomorphic functions defined on subvarieties of classical domains and their connections to 3-point Pick interpolation, we study a special class of two-dimensional algebraic subvarieties, denoted as Mα, within the unit tridisc. These subvarieties are defined as sets of the form{(z1,z2,z3)∈D3:α1z1+α2z2+α3z3=α‾1z2z3+α‾2z1z3+α‾3z1z2}. In this paper
-
Monodromy and Dulac's problem for piecewise analytical planar vector fields Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-09-07 Claudio A. Buzzi, Claudio Pessoa, João C. Medrado
Consider an analytical function f:V⊂R2→R having 0 as its regular value, a switching manifold Σ=f−1(0) and a piecewise analytical vector field X=(X+,X−), i.e. X± are analytical vector fields defined on Σ±={p∈V:±f(p)>0}. We characterize when the vector field X has a monodromic singular point in Σ, called Σ-monodromic singular point. Moreover, under certain conditions, we show that a Σ-monodromic singular
-
Schwarzian norm estimate for functions in Robertson class Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-09-07 Md Firoz Ali, Sanjit Pal
Let A denote the class of analytic functions f in the unit disk D={z∈C:|z|<1} normalized by f(0)=0, f′(0)=1. For −π/2<α<π/2, let Sα be the subclass of A consisting of functions f that satisfy the relation Re{eiα(1+zf″(z)/f′(z))}>0 for z∈D. In the present article, we determine the sharp estimate of the pre-Schwarzian and Schwarzian norms for functions in the class Sα.
-
Rigidity of proper holomorphic mappings between certain nonequidimensional unbounded non-hyperbolic domains Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-09-07 Lei Wang
The Fock-Bargmann-Hartogs domain Dn,m(μ)(μ>0) in Cn+m is defined by the inequality ‖w‖2
-
Essentially finite G-torsors Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-09-06 Archia Ghiasabadi, Stefan Reppen
Let X be a smooth projective curve of genus g, defined over an algebraically closed field k, and let G be a connected reductive group over k. We say that a G-torsor is essentially finite if it admits a reduction to a finite group, generalising the notion of essentially finite vector bundles to arbitrary groups G. We give a Tannakian interpretation of such torsors, and we prove that all essentially
-
Egg-Yolk principle for uniformizing Gromov hyperbolic domains Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-09-04 Qingshan Zhou, Yuehui He, Saminathan Ponnusamy, Qianghua Luo
Recently, there are two kinds of conformal deformations of Gromov hyperbolic domains, introduced respectively by Bonk-Heinonen-Koskela and the first author, such that the deformed spaces are uniform and Loewner spaces. Given a Gromov hyperbolic domain Ω in Rn, we prove that uniform and Loewner subdomains of Ω are also uniform and Loewner in the uniformizations of the domain Ω, respectively. As a tool
-
The Neumann problem for a class of semilinear fractional equations with critical exponent Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-08-23 Somnath Gandal, Jagmohan Tyagi
We establish the existence of solutions to the following semilinear Neumann problem for fractional Laplacian and critical exponent:{(−Δ)su+λu=|u|p−1uinΩ,Nsu(x)=0inRn∖Ω‾,u≥0inΩ, where λ>0 is a constant and Ω⊂Rn is a bounded domain with smooth boundary. Here, p=n+2sn−2s is a critical exponent, n>max{4s,8s+23}, s∈(0,1). Due to the critical exponent in the problem, the corresponding functional Jλ does
-
Successive coefficients for functions in the spirallike family Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-08-19 Vibhuti Arora, Saminathan Ponnusamy, Swadesh Kumar Sahoo, Toshiyuki Sugawa
The aim of this paper is to compute the bounds of successive coefficients ||an+1|−|an|| for the family of univalent functions that are spirallike functions of non-negative order. This result not only improves a recent result but gives an alternate simple proof for the case of univalent spirallike functions.
-
Boundary behavior of positive solutions of the heat equation on a stratified Lie group Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-08-19 Jayanta Sarkar
In this article, we are concerned with a certain type of boundary behavior of positive solutions of the heat equation on a stratified Lie group at a given boundary point. We prove that a necessary and sufficient condition for the existence of the parabolic limit of a positive solution u at a point on the boundary is the existence of the strong derivative of the boundary measure of u at that point.
-
Separation principle of time varying delayed perturbed uncertain systems Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-08-16 Ines Ellouze, Maryam Ben Salah
In this paper, we establish a separation principle in the practical sense for a class of time varying delay uncertain perturbed systems with a delay perturbation and an independent delay perturbation. Furthermore, based on Lyapunov-Krasovskii functionals, we study the possibility to stabilize globally in practical sense by an estimated state controller. Finally, an illustrative example is given to
-
Functionals for the study of lcK metrics on compact complex manifolds Bull. des Sci. Math. (IF 1.3) Pub Date : 2023-08-09 Dan Popovici, Erfan Soheil
We propose an approach to the existence problem for locally conformally Kähler metrics on compact complex manifolds by introducing and studying a functional that is different according to whether the complex dimension of the manifold is 2 or higher.