On Energy Gap Phenomena of the Whitney Spheres in Cn or CPn*

Zhang (2021), Luo and Yin (2022) initiated the study of Lagrangian submanifolds satisfying ?*T = 0 or ?*?*T = 0 in Cⁿ or C^Pn, where T = ?*h and h is the Lagrangian trace-free second fundamental form. They proved several rigidity theorems for Lagrangian surfaces satisfying ?*T = 0 or ?*?*T = 0 in C² under proper small energy assumption and gave new characterization of the Whitney spheres in C². In this paper,the authors extend these results to Lagrangian submanifolds in Cⁿ of dimension n ≥ 3 and to Lagrangian submanifolds in C^Pn.     

映射的横截性定理

Hirsch conjectured: M、N、A are differential manifolds, g∈C^∞(A,N), then the set T = {f∈C^∞(M,N)|f∈g} is dense in C∞(M,N)and open if g is proper.In this paper, we prove the transversality theorem of map in the Jet bundle.Theorem 1 Let M, N. A be differential manifolds, g∈C^∞(A,J^τ(M、N)), then the set T{f∈C^∞(M,N)|f^τf∈g } is residual in C^∞(M,N) and open if g is proper.Theorem 1 contains Thom's transversal ity theorem as a special case. We can obtain Hirsch's conjecture by using theorem 1.     

周期点集为闭集的圆周自映射周期点的周期

Let S¹ denote the circle. In this paper, we show the following.Theorem. Let f: S¹→S¹ be a continuous map and suppose f has a fixed point and the set of periodic points of f is closed, then the period of each periodic point of f is a power of 2.Corollary. Let f: S¹→S¹ be a continuous map and suppose the set of periodic points of f is closed, then there exists an odd integer m such that the set of periods of periodic points of f is contained in the set {m·2ⁿ; n = 0,1,2,…}.     

Hqp(01)空间中的多项式最佳逼近问题

In this paper, we obtained two direct theorems and a inverse theorem on the best approximation by polynomials in H_q^p(01) spaces. The results obtained in this paper are just some direct extensions from the case p= 1 to the case 0相似文献   

On the Trace Embedding and Compact Properties of Finite Element Spaces

Ⅰ. Introduction In paper, the embedding theorem and the compact theorem of Rellich and Kondrachev for the Sobolev spaces are generalized to finite element spaces with certain properties. By means of them, the convergence of finite element methods for a class of nonlinear problems are proved in papers.In this paper, the trace embedding and compact theorems for Sobolev spaces will be generalized     

共形平坦黎曼流形中具有平行第二基本形式的超曲面

In this paper, we prove the followingTheorem. Let Cⁿ⁺¹ ( n >5 ) be a conformally flat Riemannian anifola of dimension n + 1 . If Mn is a hypersurface immersed isometrically in Cⁿ⁺¹ over which the second fundamental form is covariant constant, then there are three posible cases only:I . locally Mⁿ= S^p×S^q×S^r, p+q+r=n;Ⅱ . locally Mⁿ=S^p×S^q, p + q = n , where S^k is k- dimensional Riemannian space of constant curvature;III. Mⁿ is umbilical and conformally flat. Moreover, if Mⁿ is connected and complete, then the result holds globally.     

矩阵指数的偏迹不等式

In this paper it is shown that if C is an n×n complex matrix and C^(k) is the k-th compound of C, 1≤k≤n, N = (n k) and if the eigenvalues of C^(k) are labeled inorder of decreasing magnitude |λ₁(C^(k))|≥λ₂(C^(k))|≥…≥λ_N(C^(k))|define the partial trace tr_i^(k)(C) by (?) Then for two n×n Hermrtian matrices A, B,with equality holds if A, B are commutative or k = n.     

A Generalization of Lappan’s Theorem to Higher Dimensional Complex Projective Space

In this paper, the authors discuss a generalization of Lappan’s theorem to higher dimensional complex projective space and get the following result: Let f be a holomorphic mapping of ? into Pⁿ(C), and let H₁, · · · , H_q be hyperplanes in general position in Pⁿ(C).Assume that sup {(1 ? |z|²)f^?(z) : z ∈ q[ j=1 f^?1(H_j )o < ∞,if q ≥ 2n² + 3, then f is normal.     

Mean Curvature Flow of Arbitrary Codimension in Complex Projective Spaces*

Recently, Pipoli and Sinestrari [Pipoli, G. and Sinestrari, C., Mean curvature flow of pinched submanifolds of CPⁿ, Comm. Anal. Geom., 25, 2017, 799–846] initiated the study of convergence problem for the mean curvature flow of small codimension in the complex projective space CP^m. The purpose of this paper is to develop the work due to Pipoli and Sinestrari, and verify a new convergence theorem for the mean curvature flow of arbitrary codimension in the complex projective space. Namely, the authors prove that if the initial submanifold in CP^m satisfies a suitable pinching condition, then the mean curvature flow converges to a round point in finite time, or converges to a totally geodesic submanifold as t → ∞. Consequently, they obtain a differentiable sphere theorem for submanifolds in the complex projective space.     

Generalized Persistence of Entropy Weak Solutions for System of Hyperbolic Conservation Laws

Let u(t, x) be the solution to the Cauchy problem of a scalar conservation law in one space dimension. It is well known that even for smooth initial data the solution can become discontinuous in finite time and global entropy weak solution can best lie in the space of bounded total variations. It is impossible that the solutions belong to, for example, H¹ because by Sobolev embedding theorem H¹ functions are H¨older continuous. However, the author notes that from any point (t, x), he can draw a generalized characteristic downward which meets the initial axis at y = α(t, x). If he regards u as a function of (t, y), it indeed belongs to H¹ as a function of y if the initial data belongs to H¹ . He may call this generalized persistence (of high regularity) of the entropy weak solutions.The main purpose of this paper is to prove some kinds of generalized persistence (of high regularity) for the scalar and 2 × 2 Temple system of hyperbolic conservation laws in one space dimension.     

Lp Solutions for Multidimensional BDSDEs with Locally Weak Monotonicity Coefficients

In this paper, the authors establish the existence and uniqueness theorem of L^p (1 < p ≤ 2) solutions for multidimensional backward doubly stochastic differential equations (BDSDEs for short) under the p-order globally (locally) weak monotonicity conditions. Comparison theorem of L^p solutions for one-dimensional BDSDEs is also proved.These conclusions unify and generalize some known results.     

关于组合合成阵

We define the r^th combinatorial compound C_r^*(A) of a matrix A, which can be viewed as the characteristic function of the subset of the rxr submatrices of A which are combinatorially nonsingular. We prove that for 1≤rr^*(A)is. We determine the minimum number of 2×2 and 3×3 combinatorially nonsingular submatrices over all n×n fully indecomposable matrices and make a jecture for general r.     

Spectral flow,Llarull's rigidity theorem in odd dimensions and its generalization

For a compact spin Riemannian manifold(M,g^{T M}) of dimension n such that the associated scalar curvature k^{T M} verifies that k^{T M}≥n(n-1),Llarull’s rigidity theorem says that any area-decreasing smooth map f from M to the unit sphere Sⁿ of nonzero degree is an isometry.In this paper,we present a new proof of Llarull’s rigidity theorem in odd dimensions via a spectral flow argument.This approach also works for a generalization of Llarull’s theorem when the...     

平稳弱相关过程积分的收敛性

Lei g(x,ω) be a stationary weakly conelated process, G(t, x) be the Green's function and G(x) be a function with a smooth one-order derivative. Define stochastic processes ξ(t,ω)=∫₀¹G(t,x)g(x,ω)dx (0≤t≤1) and η(t,ω)=∫₀^tG(x)g(x,ω)dx (0≤t≤T) In this paper we give the strong approximations of random variables ξ(t) and η(t) to normal variables, and also give a weakly in variance principle for process η(·).     

COUNTABLE HOMOGENEOUS MARKOV PROCESSES WITH IDENTICAL HITTING DISTRIBUTIONS

A theorem of Blumentbal； Getoor and McKean (1962) states： Let both X (t) and X^*(t) be Hunt processes, then they have identical hitting distributions if there exists a continuous random time substitute Z(t) such that X(Z(t) and X^*(t) have identical transition functions. In this paper an analogous theorem is established for countable homogeneoue Markov processes with conservative Q-matrix (in general, they are not Hunt processes),and another necessary and sufficient condition is found.     

THE DETERMINATION OF SIGNIFICANT DIGITS OF THE NUMERICAL SOLUTION OF LINEAR EQUATIONS

In this paper,the main results are concluded in theorem 1 and theorem 4.Theorem 1 Let A,b be nxn matrix and re-dimensional vector respectively,which can be represented exactly in the computer.If W is a nonsingu-lar nXn matrix such that ||I-WA||<1 then for any algorithm the errors of the sulution of linear equations Ax - b (1) satisfy the following inequalities     

关于M/G/l随机服务系统中L.Takacs引理的证明

L. Takacs' Lemma (ef [1] PP47-48) is a very important tool for the investigation of the transient behavior of the M/G/1 System. But the original proof contains a gap when γ(s, w) is expanded into Lagrange series by means of Lagrange theorem as given in the appendix of [1]. This is due to the fact that φ(s)=∫₀^∞e^-sxdH(x), the Laplace transform of the service time distribution , may not be analytic at s=0. An example of such a distrbution function H(x) is gives and a specific Lagrange theorem is proved By using this specific theorem, the gap in the original proof of Takacs′ Lemms is eliminated.     

6q+1级2—传递置换群,q为素数

In [ 3 ] M. D. Atkinson conjectured that if G is a doubly transitive but not doubly primitive permutation group on Ω, then G is of one of the following four types: i) Metacyclic groups of prime degree p and of order p(p -1); ii) Groups of degree 2^p and of order 2^p(2^p-1)or 2^p(2^p-l)p for some prime p;iii)Gr-oups of automorphisms of a block design with λ=1; iv) Sz(q)≤G≤Aut(Sz(g)).In this paper we proved this conjecture in a special case without using the result of classification of finte simple groups, Qur explicit result is as follows: Theorem. Let G be a doubly transitive group on set Ω,where |Ω|=6q+1 and q is a prime, then one of the following holds: i)G is doubly primitive on Ω;ii) G is sharply doubly transitive on Ω; iii) G is a groups of automorphisms of a block design with λ=1.     

逻辑导数与逻辑积分

Walsh analysis has evolved over the past decade and the end of the development is nowhere in sight. However, it is sure that the logical derivatives and integrals, or p-adic derivatives and integrals, play a very important role in Walsh analysis. In this paper, we introduce the concept of p-adic integrals in L_(0,∞)^q,1≤q≤2 , study some properties of them and obtain the relation between p-adic derivative and integral.     

关于有限域中原根分布的注记

Let f₁(x) , …,f_r(x) denote quadratfree polynomials over GF(q) that are relatively prime in pairs and of degree≥1. We have proved that if q≥(k-1)²(2^rω(q-1)-1)², then all the f_i(ξ) are primitive roots of GF(q) for some ξ∈GF(q), where k =degf₁+…+degf_r . With extending the results obtained by Wang Juping, Sun Qi and Han Wenbao respectively, we have also given a quantitative analysis of Carlitz's result.