具非负Ricci曲率和次大体积增长的流形

设M是具非负Ricci曲率的n维黎曼流形,其截曲率有下界,对M中的任意的点p有vol[B(p,r)]/rn-1=αM+o(1/rn-1)且假设函数f(r)=vol[B(p,r)]/2In(r)rn-1是单调递减的,则M具有限拓扑型,其中In(r)是一有界函数.     

The spectrum of compact hypersurface in sphere

Let M be a compact minimal hypersurface of sphere Sn 1(1). Let (M) be H (r)-torus of sphere Sn 1 (1).Assume they have the same constant mean curvature H, the result in [1] is that ifSpec0(M, g) =Spec0((M), g),then for 3≤ n ≤ 6, r2≤n-1/n or n ≥ 6, r2 ≥ n-1, then M is isometric to (M). We improved the result and prove that: if Spec0(M,g) =Spec0((M),g), then M is isometric to (M). Generally, if Specp(M,g) =Specp((M),g), here p is fixed and satisfies that n(n - 1) ≠ 6p(n - p), then M is isometric to (M).     

An order preserving inequality for three operators via furuta inequality

Furuta showed that if A≥B≥0,then for each r≥0,f（p）=（A^r/2 B^p A^r/2）^t＋r/p＋r is decreasing for p≥t≥0.Using this result,the following inequality（C^r/2（AB^2A）^δC^ r/2）^ p-1＋r/4δ＋r ≤C^p-1＋r is obtained for 0〈p ≤1,r≥1,1/4≤δ≤1 and three positive operators A, B, C satisfy（A^1/2BA^1/2）^p/2≤A^p,（B^1/2AB^1/2）^p/2≥B^p,（C^1/2AC^1/2）^p/2≤C^p,（A^1/2CA^1/2）^p/2≥A^p.     

函数F(α)=的最优单调区间

设p≥0且A,B是Hilbert空间上两个正算子,Furuta给出若A≥B＞0,那么对任意r≥0,F(α)=(ArBαAr)p+2r/α+2r是关于α≥p单调递减的,但是他指出这个结果在0≤α≤p和r≥0的条件下并不一定成立.本文给出(1)如果-1/2＜r＜0且p＜-2r,那么F(α)在[-p-4r,+∞)及(-∞,p]上单调递减,并且这两个区间不能扩大;(2)如果-1/2＜r＜0且p＞-2r,那么F(α)在(-∞,-p-4r]及[p,+∞)上单调递增,并且这两个区间不能扩大;(3)如果r＞0,p＞0,那么[p,+∞)也是F(α)的最佳单调区间.     

NOTES ON GLAISHER＇S CONGRUENCES

Let p be an odd prime and let n≥1,k≥0 and r be integers,denote by Bk the kth Bernoulli number,It is proved that(i) If r≥1 is odd and suppose 1≥r+4,then ∑j=1^p-1 1/(np+j)^r=-(2n+1)r(r+1)/2(r+2)Bp-r-2p^2(mod p^3).(ii)If r≥2 is even and suppose p≥r+3, then p-1∑j=1 1/(np+j)^r=r/r+1Bv-r-1p(mod P^2).(iii) p-1∑j=1 1/(np+j)p-2=-(2n+1)p(mod P^2).This result generalizes the Glaisher‘s congruence. As a corollary, a generalization of the Wolsten-holme‘s theorem is obtained.     

NOTES ON GLAISHER''''S CONGRUENCES

Let p be an odd prime and let n ≥ 1,k ≥ 0 and r be integers. Denote by Bk the kth Bernoulli number. It is proved that (i) If r≥1 is odd and suppose p≥r+4, thenp-1∑j=11/(np+j)=-(2n+1+(x+1)/2(x+2)Bp-r-2p2(modp3).(ii)IFr≥2is even and suppose p≥r+3,thenp-1∑j=11/(np+j)+=r/r+1Bp-x-1p(modp2).(iii)p-1∑j=11/(np+j)p-2=-(2n+1)p(modp2).Thisesult generalizes the Glaisher's congruence. As a corollary, a generalization of the Wolstenholme's theorem is obtained.     

关于三个算子的算子不等式(英文)

As a generalization of grand Furuta inequality,recently Furuta obtain：If A≥ B≥0 with A0,then for t∈[0,1]and p1,p2,p3,p4≥1, A t 2[A- t 2{A t 2（A/ t 2 Bp 1A /t2 ）p 2A t 2}p 3A -t2 ]p 4A t 2 1 [{（p1/t）p2＋t}p3-t]p4＋t]≤A. In this paper,we generalize this result for three operators as follow：If A≥B≥C≥0 with B0,t∈[0,1]and p1,p2,···,p2n/1,p2n≥1 for a natural number n.Then the following inequalities hold for r≥t, A1/t＋r≥ [A r 2[B /t 2{B t 2······[B /t 2{B t 2（B /t 2 ←B /t 2 n times Bt 2 n/1 times by turns Cp 1B /t 2）p 2B t 2}p 3B /t 2]p 4···B t 2}p 2n/1B /t 2 B /t 2 n times Bt 2 n/1 times by turns→ ]p 2nA r 2] 1/t＋r q[2n]＋r/t, where q[2n]≡{···[{[（p1-t）p2＋t]p3/t}p4＋t]p5/···/t}p2n＋t /t and t alternately n times appear .     

起始为指数律的P—函数振荡问题

设y是标准p-函数类。对u>0令 y(u)={p∈yq≥0,p(t)=e~(-qt),0≤t≤u}在[9]Kingman证明了:如果p∈y(u)则p(t)≤e~(-1) e~(-qu)(t≥u),而在[4]中Griffeath进一步证明了:p(t)≤e~(-(1-e~(-qu)))(t≥u)。本文首先给出这一结果一个完全不同的新证明。然后证明下面的结果:如果p∈y(u),s≥u,p(t),m=P(s)则p(t)≤max(M,m e~(-1 m))(t≥u)。本文的第二个结果叙述如下:记 m(M,p)=inf{p(t):0≤t≤1,p(1)=M},p∈y I(M,u)=inf{m(M,p):p∈y(u)},I(M)=inf{m(M,p):p∈y} I~(M,u),v_0=inf{M>0:I(M)>0} v(M)=inf{M>0:I(M)>0}则v_0=v~。     

FUNDAMENTAL GROUPS OF CLOSED POSITIVELY CURVED MANIFOLDS WITH ALMOST DISCRETE ABELIAN GROUP ACTIONS

Let M be a closed n-manifold of positive sectional curvature.Assume that M admits an effiective isometrical T 1×Zkp-action with p prime.The main result of the article is that if k=1 for n=3 or k (n+1)/4 for n≥5,then there exists a positive constant p(n),depending only on n,such that π1(M) is cyclic if p≥p(n).     

一类非线性种群发展方程非局部柯西问题随机周期解的存在性

研究如下形式具有随机周期移民扰动的非线性种群发展方程的非局部柯西问题，{δp（r,t）/δt＋δp（r,t）/δr=-μ（r）p（r,t）＋f（t,p（r,t））,0＜r＜rm,t≥0,p（r,0）=p0（r）＋g（p（r,t0））,T＞t0＞0 p（0,t）=β（t）∫^r2 r1（k（r）h（r）p（r,t）dr这里，其他地区的种群迁入项厂以及非局部条件项g为紧算子，且厂是时间变量t的周期为T的周期函数．利用Shesfer不动点定理，可以证明上述柯西问题随机周期积分解的存在性．这篇论文的结果推广了前人的工作．