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1.
The mathematics needed for establishing the concept of point-like curvature in fractal-Cantorian spacetime are introduced. The corresponding energy expressions are derived. For a Cantorian spacetime manifold modeled by a fuzzy K3 Kähler it is found that the total curvature corresponding to a Hausdorff dimension 4 + 3 = 4.236067977 is K = 26 + k = 26.18033989. The corresponding internal energy is shown to be given by the dimension of Munroe’s quasi exceptional Lie symmetry group E12, namely 685.4101968. It should be noted that with K found explicitly and as a function of the resolution, writing the equivalent Lagrangian of E-infinity becomes trivial and in addition the dynamics of the theory is manifested in the corresponding Wyle golden ring scaling.  相似文献   

2.
This article concerns the structure of complete noncompact stable hypersurfaces M n with constant mean curvature H > 0 in a complete noncompact oriented Riemannian manifold N n+1. In particular, we show that a complete noncompact stable constant mean curvature hypersurface M n , n = 5, 6, in the Euclidean space must have only one end. Any such hypersurface in the hyperbolic space with , respectively, has only one end.  相似文献   

3.
We prove firstly the classification theorem for p-harmonic morphisms between Euclidean domains. Secondly, we show that if is a p-harmonic morphism (p ≥ 2) from a complete Riemannian manifold M of nonnegative Ricci curvature into a Riemannian manifold N of non-positive scalar curvature such that the L q -energy is finite, then is constant, which improve the corresponding result due to G. Choi, G. Yun in (Geometriae Dedicata 101 (2003), 53–59).   相似文献   

4.
We let (M,g) be a noncompact complete Riemannian manifold of dimension n 3 whose scalar curvature S(x) is positive for all x in M. With an assumption on the Ricci curvature and scalar curvature at infinity, we study the behavior of solutions of the Yamabe equation on –u+[(n–2)/(4(n–1))]Su=qu (n+2)/(n–2) on (M,g). This study finds restrictions on the existence of an injective conformal immersion of (M,g) into any compact Riemannian n -manifold. We also show the existence of a complete conformal metric with constant positive scalar curvature on (M,g) with some conditions at infinity.  相似文献   

5.
6.
Suppose (N n , g) is an n-dimensional Riemannian manifold with a given smooth measure m. The P-scalar curvature is defined as ${P(g)=R^m_\infty(g)=R(g)-2\Delta_g{\rm log}\,\phi-|\nabla_g{\rm log}\,\phi|_g^2}Suppose (N n , g) is an n-dimensional Riemannian manifold with a given smooth measure m. The P-scalar curvature is defined as P(g)=Rm(g)=R(g)-2Dglog f-|?glog f|g2{P(g)=R^m_\infty(g)=R(g)-2\Delta_g{\rm log}\,\phi-|\nabla_g{\rm log}\,\phi|_g^2}, where dm=f dvol(g){dm=\phi\,dvol(g)} and R(g) is the scalar curvature of (N n , g). In this paper, under a technical assumption on f{\phi}, we prove that f{\phi}-stable minimal oriented hypersurface in the three-dimensional manifold with nonnegative P-scalar curvature must be conformally equivalent to either the complex plane \mathbbC{\mathbb{C}} or the cylinder \mathbbR×\mathbbS1{\mathbb{R}\times\mathbb{S}^1}.  相似文献   

7.
We study the Klein–Gordon equation coupled with an interaction term (□+m2)φ+λφp=0. In the linear case (λ=0) a kind of generalized Noether's theorem gives us a conserved quantity. The purpose of this paper is to find an analogue of this conserved quantity in the interacting case. We will see that we can do this perturbatively, and we define explicitly a conserved quantity, using a perturbative expansion based on Planar Trees and a kind of Feynman rule. Only the case p=2 is treated but our approach can be generalized to any p-theory.  相似文献   

8.
We consider the generalized evolution of compact level sets by functions of their normal vectors and second fundamental forms on a Riemannian manifold M. The level sets of a function evolve in such a way whenever u solves an equation u t  + F(Du, D 2 u) = 0, for some real function F satisfying a geometric condition. We show existence and uniqueness of viscosity solutions to this equation under the assumptions that M has nonnegative curvature, F is continuous off {Du = 0}, (degenerate) elliptic, and locally invariant by parallel translation. We then prove that this approach is geometrically consistent, hence it allows to define a generalized evolution of level sets by very general, singular functions of their curvatures. For instance, these assumptions on F are satisfied when F is given by the evolutions of level sets by their mean curvature (even in arbitrary codimension) or by their positive Gaussian curvature. We also prove that the generalized evolution is consistent with the classical motion by the corresponding function of the curvature, whenever the latter exists. When M is not of nonnegative curvature, the same results hold if one additionally requires that F is uniformly continuous with respect to D 2 u. Finally we give some counterexamples showing that several well known properties of the evolutions in are no longer true when M has negative sectional curvature. D. Azagra was supported by grants MTM-2006-03531 and UCM-CAM-910626. M. Jimenez-Sevilla was supported by a fellowship of the Ministerio de Educacion y Ciencia, Spain. F. Macià was supported by program “Juan de la Cierva” and projects MAT2005-05730-C02-02 of MEC (Spain) and PR27/05-13939 UCM-BSCH (Spain).  相似文献   

9.
A d-dimensional dual hyperoval with monomial is of polar type if and only if d is even, Gal(GF(2d+1)/GF(2)) and σ2=idGF(2d+1).  相似文献   

10.
The present short note gives for the first time a derivation of the inverse electromagnetic fine structure constant from the elementary particles content of the standard model plus graviton and the Higgs. It is the first derivation ever to interpret as the familiar Nf = (2)(48) = 96 Fermions and NB = (2)(15) = 30 Bosons of the standard model plus the eleven dimensions D = 11 of super gravity spacetime . The exact theoretical value 137.082039325 and the accurate experimental results are also given clear mathematical derivation showing that all of the 137 and not only the 96 + 30 = 126 may be interpreted as physical particles so that in a sense elementary particles create and span spacetime.  相似文献   

11.
Consider the class of n-dimensional Riemannian spin manifolds with bounded sectional curvatures and bounded diameter, and almost non-negative scalar curvature. Let r = 1 if n = 2,3 and r = 2[n/2]-1 + 1 if n ≥ 4. We show that if the square of the Dirac operator on such a manifold has r small eigenvalues, then the manifold is diffeomorphic to a nilmanifold and has trivial spin structure. Equivalently, if M is not a nilmanifold or if M is a nilmanifold with a non-trivial spin structure, then there exists a uniform lower bound on the r-th eigenvalue of the square of the Dirac operator. If a manifold with almost non-negative scalar curvature has one small Dirac eigenvalue, and if the volume is not too small, then we show that the metric is close to a Ricci-flat metric on M with a parallel spinor. In dimension 4 this implies that M is either a torus or a K3-surface.   相似文献   

12.
In this paper, we prove the following theorem regarding the Wang–Yau quasi-local energy of a spacelike two-surface in a spacetime: Let Σ be a boundary component of some compact, time-symmetric, spacelike hypersurface Ω in a time-oriented spacetime N satisfying the dominant energy condition. Suppose the induced metric on Σ has positive Gaussian curvature and all boundary components of Ω have positive mean curvature. Suppose HH 0 where H is the mean curvature of Σ in Ω and H 0 is the mean curvature of Σ when isometrically embedded in \mathbb R3{\mathbb R^3} . If Ω is not isometric to a domain in \mathbb R3{\mathbb R^3}, then
1.  the Brown–York mass of Σ in Ω is a strict local minimum of the Wang–Yau quasi-local energy of Σ.  相似文献   

13.
An important problem in the study of Ricci flow is to find the weakest conditions that provide control of the norm of the full Riemannian curvature tensor. In this article, supposing (M n , g(t)) is a solution to the Ricci flow on a Riemmannian manifold on time interval [0, T), we show that L\fracn+22{L^\frac{n+2}{2}} norm bound of scalar curvature and Weyl tensor can control the norm of the full Riemannian curvature tensor if M is closed and T < ∞. Next we prove, without condition T < ∞, that C 0 bound of scalar curvature and Weyl tensor can control the norm of the full Riemannian curvature tensor on complete manifolds. Finally, we show that to the Ricci flow on a complete non-compact Riemannian manifold with bounded curvature at t = 0 and with the uniformly bounded Ricci curvature tensor on M n  × [0, T), the curvature tensor stays uniformly bounded on M n  × [0, T). Hence we can extend the Ricci flow up to the time T. Some other results are also presented.  相似文献   

14.
Let be an immersion of a complete n-dimensional oriented manifold. For any v∈ℝ n+2, let us denote by v :M→ℝ the function given by v (x)=〈φ(x),v〉 and by f v :M→ℝ, the function given by f v (x)=〈ν(x),v〉, where is a Gauss map. We will prove that if M has constant mean curvature, and, for some v≠0 and some real number λ, we have that v =λ f v , then, φ(M) is either a totally umbilical sphere or a Clifford hypersurface. As an application, we will use this result to prove that the weak stability index of any compact constant mean curvature hypersurface M n in which is neither totally umbilical nor a Clifford hypersurface and has constant scalar curvature is greater than or equal to 2n+4. A. Brasil Jr. was partially supported by CNPq, Brazil, 306626/2007-1.  相似文献   

15.
We show that, up to some natural normalizations, the moduli space of singly periodic complete embedded maximal surfaces in the Lorentz–Minkowski space , with fundamental piece having a finite number (n + 1) of singularities, is a real analytic manifold of dimension 3n + 4. The underlying topology agrees with the topology of uniform convergence of graphs on compact subsets of {x 3 = 0}.   相似文献   

16.
17.
In this paper we study Einstein-Weyl structures in the framework of contact metric manifolds. First, we prove that a complete K-contact manifold admitting both the Einstein-Weyl structures W ± = (g, ±ω) is Sasakian. Next, we show that a compact contact metric manifold admitting an Einstein-Weyl structure is either K-contact or the dual field of ω is orthogonal to the Reeb vector field, provided the Reeb vector field is an eigenvector of the Ricci operator. We also prove that a contact metric manifold admitting both the Einstein-Weyl structures and satisfying is either K-contact or Einstein. Finally, a couple of results on contact metric manifold admitting an Einstein-Weyl structure W = (g, f η) are presented.   相似文献   

18.
套代数上的广义Jordan中心化子   总被引:2,自引:1,他引:1  
杨翠  张建华 《数学学报》2010,53(5):975-980
设H是实数域或复数域F上的Hilbert空间,N为H上的非平凡套,τ(N)为相应的套代数,并且φ:τ(N)→τ(N)是一个可加映射.本文证明了如果存在正整数m,n,p,使得(m+n)φ(A~(p+1))=mφ(A)A~p+nA~pφ(A)或φ(A~(m+n+1))=A~mφ(A)A~n对所有的A∈τ(N)成立,则存在λ∈F,使得对所有的A∈τ(N),有φ(A)=λA.  相似文献   

19.
A self-transverse immersion of a smooth manifold M8k in has a double point self-intersection set which is the image of an immersion of a smooth four-dimensional manifold, cobordent to P4, P2×P2, P4+P2×P2 or a boundary. We will prove that for any value of k>1 the double point self-intersection set is a boundary. If k=1, then there exists an immersion of P2×P2×P2×P2 in with double point manifold boundary and odd number of triple points. In particular any immersion of oriented manifold in this dimension has double point manifold cobordant to a boundary.  相似文献   

20.
The present paper shows that the algebra generated by {C|  Aut(Bn)} is cyclic on H2(Bn), and any nonconstant function f  H2(Bn) is a cyclic vector of . In addition, the hypercyclic and cyclic composition operators will be discussed.  相似文献   

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