共查询到20条相似文献,搜索用时 15 毫秒
1.
Alessio Martini 《Mathematische Zeitschrift》2010,265(4):831-848
The Heisenberg–Pauli–Weyl (HPW) uncertainty inequality on
\mathbbRn{\mathbb{R}^n} says that
|| f ||2 £ Ca,b|| |x|a f||2\fracba+b|| (-D)b/2f||2\fracaa+b.\| f \|_2 \leq C_{\alpha,\beta}\| |x|^\alpha f\|_2^\frac{\beta}{\alpha+\beta}\| (-\Delta)^{\beta/2}f\|_2^\frac{\alpha}{\alpha+\beta}. 相似文献
2.
P. van der Cruyssen 《BIT Numerical Mathematics》1982,22(4):533-537
Consider the (n+1)st order nonhomogeneous recursionX
k+n+1=b
k
X
k+n
+a
k
(n)
X
k+n-1+...+a
k
(1)
X
k
+X
k
.Leth be a particular solution, andf
(1),...,f
(n),g independent solutions of the associated homogeneous equation. It is supposed thatg dominatesf
(1),...,f
(n) andh. If we want to calculate a solutiony which is dominated byg, but dominatesf
(1),...,f
(n), then forward and backward recursion are numerically unstable. A stable algorithm is derived if we use results constituting a link between Generalised Continued Fractions and Recursion Relations. 相似文献
3.
The complementarity problem with a nonlinear continuous mappingf from the nonnegative orthantR
+
n
ofR
n intoR
n can be written as the system of equationsF(x, y) = 0 and(x, y) R
+
2n
, whereF denotes the mapping from the nonnegative orthantR
+
2n
ofR
2n intoR
+
n
× Rn defined byF(x, y) = (x
1y1,,xnyn, f1(x) – y1,, fn(x) – yn) for every(x, y) R
+
2n
. Under the assumption thatf is a uniformP-function, this paper establishes that the mappingF is a homeomorphism ofR
+
2n
ontoR
+
n
× Rn. This result provides a theoretical basis for a new continuation method of tracing the solution curve of the one parameter family of systems of equationsF(x, y) = tF(x
0, y0) and(x, y) R
+
2n
from an arbitrary initial point(x
0, y0) R
+
2n
witht = 1 until the parametert attains 0. This approach is an extension of the one used in the polynomially bounded algorithm recently given by Kojima, Mizuno and Yoshise for solving linear complementarity problems with positive semi-definite matrices. 相似文献
4.
Chmielinski has proved in the paper [4] the superstability of the generalized orthogonality equation |〈f(x), f(y)〉| = |〈x,y〉|. In this paper, we will extend the result of Chmielinski by proving a theorem: LetD
n be a suitable subset of ℝn. If a function f:D
n → ℝn satisfies the inequality ∥〈f(x), f(y)〉| |〈x,y〉∥ ≤ φ(x,y) for an appropriate control function φ(x, y) and for allx, y ∈ D
n, thenf satisfies the generalized orthogonality equation for anyx, y ∈ D
n. 相似文献
5.
J. Gwoździewicz 《Commentarii Mathematici Helvetici》1999,74(3):364-375
Let f be a real analytic function defined in a neighborhood of
0 ? \Bbb Rn 0 \in {\Bbb R}^n such that f-1(0)={0} f^{-1}(0)=\{0\} . We describe the smallest possible exponents !, #, / for which we have the following estimates: |f(x)| 3 c|x|a |f(x)|\geq c|x|^{\alpha} , |grad f(x)| 3 c|x|b |{\rm grad}\,f(x)|\geq c|x|^{\beta} , |grad f(x)| 3 c|f(x)|q |{\rm grad}\,f(x)|\geq c|f(x)|^{\theta} for x near zero with c > 0 c > 0 . We prove that a = b+1 \alpha=\beta+1, q = b/a\theta=\beta/\alpha . Moreover b = N+a/b \beta=N+a/b where $ 0 h a < b h N^{n-1} $ 0 h a < b h N^{n-1} . If f is a polynomial then |f(x)| 3 c|x|(degf-1)n+1 |f(x)|\geq c|x|^{(\deg f-1)^n+1} in a small neighborhood of zero. 相似文献
6.
Endre Pap 《Algebra Universalis》1992,29(3):338-345
Swamy studied the natural metric ¦x–y¦ on Abelian lattice-ordered groupsG, and he proved that the stable isometries which preserve this metric have to be automorphisms ofG. Holland proved that the only intrinsic metrics on lattice-ordered groups, i.e., invariant and symmetric metrics, are the multiples n¦x –y¦ for some integern. We show that iff is an arbitrary surjection from an Abelian lattice-ordered groupG
1 onto an Archimedean Abelian lattice-ordered groupG
2 such that f(0)]0 and, for some non-zero intrinsic metricsD andd, D(f(x),f(y)) depends functionally on d(x,y), thenf is a homomorphism of G1 onto G2.Presented by R. S. Pierce. 相似文献
7.
The finite generators of Abelian integral are obtained, where Γh is a family of closed ovals defined by H(x,y)=x2+y2+ax4+bx2y2+cy4=h, h∈Σ, ac(4ac−b2)≠0, Σ=(0,h1) is the open interval on which Γh is defined, f(x,y), g(x,y) are real polynomials in x and y with degree 2n+1 (n?2). And an upper bound of the number of zeros of Abelian integral I(h) is given by its algebraic structure for a special case a>0, b=0, c=1. 相似文献
8.
We consider the family f
a,b
(x,y)=(y,(y+a)/(x+b)) of birational maps of the plane and the parameter values (a,b) for which f
a,b
gives an automorphism of a rational surface. In particular, we find values for which f
a,b
is an automorphism of positive entropy but no invariant curve. The Main Theorem: If f
a,b
is an automorphism with an invariant curve and positive entropy, then either (1) (a,b) is real, and the restriction of f to the real points has maximal entropy, or (2) f
a,b
has a rotation (Siegel) domain.
Research supported in part by the NSF. 相似文献
9.
10.
Zhu Xuexian 《逼近论及其应用》2001,17(4):65-76
Let Mg be the maximal operator defined by
|