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1.
We have studied the time reversal symmetry violation on the bases of the configuration mixing model and E-infinity theory. With the use of the Cabibbo angle approximation, we have presented the transformation matrix in terms of the golden ratio (?), and shown that the time reversal symmetry violation is described by the configuration mixing of the unstable and stable manifolds (Wu, Ws). The magnitude of the mixing for the weak interaction field is given by the expression sin2 θT(theor)  sin4 θC(theor)  (?)12 = 3.105 × 10?3, which is compared to the Kaon decay experiment ~2.3 × 10?3. We have also discussed the space–time symmetry violation by using the CPT theorem.  相似文献   

2.
For fixed positive integer k, let En denote the set of lattice paths using the steps (1, 1), (1,  1), and (k, 0) and running from (0, 0) to (n, 0) while remaining strictly above the x-axis elsewhere. We first prove bijectively that the total area of the regions bounded by the paths of En and the x-axis satisfies a four-term recurrence depending only on k. We then give both a bijective and a generating function argument proving that the total area under the paths of En equals the total number of lattice points on the x-axis hit by the unrestricted paths running from (0, 0) to (n  2, 0) and using the same step set as above.  相似文献   

3.
It is known that quantum computers yield a speed-up for certain discrete problems. Here we want to know whether quantum computers are useful for continuous problems. We study the computation of the integral of functions from the classical Hölder classes Fkαd on [0, 1]d and define γ by γ=(k+α)/d. The known optimal orders for the complexity of deterministic and (general) randomized methods are comp(Fkαdε)≍ε−1/γ and comprandom(Fkαdε)≍ε−2/(1+2γ). For a quantum computer we prove compquantquery(Fkαdε)≍ε−1/(1+γ) and compquant(Fkαdε)⩽−1/(1+γ)(log ε−1)1/(1+γ). For restricted Monte Carlo (only coin tossing instead of general random numbers) we prove compcoin(Fkαdε)⩽−2/(1+2γ)(log ε−1)1/(1+2γ). To summarize the results one can say that    there is an exponential speed-up of quantum algorithms over deterministic (classical) algorithms, if γ is small;    there is a (roughly) quadratic speed-up of quantum algorithms over randomized classical methods, if γ is small.  相似文献   

4.
The support of an [n, k] linear code C over a finite field Fq is the set of all coordinate positions such that at least one codeword has a nonzero entry in each of these coordinate position. The rth generalized Hamming weight dr(C), 1  r  k, of C is defined as the minimum of the cardinalities of the supports of all [n, r] subcodes of C. The sequence (d1(C), d2(C),  , dk(C)) is called the Hamming weight hierarchy (HWH) of C. The HWH, dr(C) = n  k + r;  r = 1, 2 , …, k, characterizes maximum distance separable (MDS) codes. Therefore the matrix characterization of MDS codes is also the characterization of codes with the HWH dr(C) = n  k + r; r = 1, 2,  , k. A linear code C with systematic check matrix [IP], where I is the (n  k) × (n  k) identity matrix and P is a (n  k) × k matrix, is MDS iff every square submatrix of P is nonsingular. In this paper we extend this characterization to linear codes with arbitrary HWH. Using this result, we characterize Near-MDS codes, Near-Near-MDS (N2-MDS) codes and Aμ-MDS codes. The MDS-rank of C is the smallest integer η such that dη+1 = n  k + η + 1 and the defect vector of C with MDS-rank η is defined as the ordered set {μ1(C), μ2(C), μ3(C),  , μη(C), μη+1(C)}, where μi(C) = n  k + i  di(C). We call C a dually defective code if the defect vector of the code and its dual are the same. We also discuss matrix characterization of dually defective codes. Further, the codes meeting the generalized Greismer bound are characterized in terms of their generator matrix. The HWH of dually defective codes meeting the generalized Greismer bound are also reported.  相似文献   

5.
《Journal of Algebra》2002,247(2):467-508
In this paper we shall generalize the notion of an integral on a Hopf algebra introduced by Sweedler, by defining the more general concept of an integral of a threetuple (H, A, C), where H is a Hopf algebra coacting on an algebra A and acting on a coalgebra C. We prove that there exists a total integral γ: C  Hom(C, A) of (H, A, C) if and only if any representation of (H, A, C) is injective in a functorial way, as a corepresentation of C. In particular, the quantum integrals associated to Yetter–Drinfel'd modules are defined. Let now A be an H-bicomodule algebra, HYDA the category of quantum Yetter–Drinfel'd modules, and B = {a  A|∑S 1(a〈1〉)a  1〉  a〈0〉 = 1H  a}, the subalgebra of coinvariants of the Verma structure A  HYDA. We shall prove the following affineness criterion: if there exists γ: H  Hom(H, A) a total quantum integral and the canonical map β: A  B A  H  A, β(a  B b) = S 1(b〈1〉)b  1〉  ab〈0〉 is surjective (i.e., A/B is a quantum homogeneous space), then the induction functor –  B A: MB  HYDA is an equivalence of categories. The affineness criteria proven by Cline, Parshall, and Scott, and independently by Oberst (for affine algebraic groups schemes) and Schneider (in the noncommutative case), are recovered as special cases.  相似文献   

6.
LetEbe a real Banach space with a uniformly convex dual spaceE*. SupposeT:E  Eis a continuous (not necessarily Lipschitzian) strongly accretive map such that (I  T) has bounded range, whereIdenotes the identity operator. It is proved that the Ishikawa iterative sequence converges strongly to the unique solution of equationTx = f,f  E. Our results extend and complement the recent results obtained by Chidume.  相似文献   

7.
《Journal of Algebra》2002,247(1):244-267
J. Chuang, R. Kessar, and J. Rickard have proved Broué's Abelian defect group conjecture for many symmetric groups. We adapt the ideas of Kessar and Chuang towards finite general linear groups (represented over non-describing characteristic). We then describe Morita equivalences between certain p-blocks of GLn(q) with defect group Cpα × Cpα, as q varies (see Theorem 2). Here p and q are coprime. This generalizes work of S. Koshitani and M. Hyoue, who proved the same result for principal blocks of GLn(q) when p = 3, α = 1, in a different way.  相似文献   

8.
《Journal of Complexity》1999,15(1):17-29
Consider an arithmetic expression of lengthninvolving only the operations {+, ×} and non-negative constants. We prove lower bounds on the depth of any binary computation tree over the same sets of operations and constants that computes such an expression. We exhibit a family of arithmetic expressions that requires computation trees of depth at least 1.5 log2 nO(1), thus proving a conjecture of S. R. Kosaraju (1986,in“Proc. of the 18th ACM Symp. on Theory Computing,” pp. 231–239). In contrast, Kosaraju showed how to compute such expressions with computation trees of depth 2 log2 n+O(1).  相似文献   

9.
In this paper the statistical properties of nucleotides in human chromosomes 21 and 22 are investigated. The n-tuple Zipf analysis with n = 3, 4, 5, 6, and 7 is used in our investigation. It is found that the most common n-tuples are those which consist only of adenine (A) and thymine (T), and the rarest n-tuples are those in which GC or CG pattern appears twice. With the n-tuples become more and more frequent, the double GC or CG pattern becomes a single GC or CG pattern. The percentage of four nucleotides in the rarest ten and the most common ten n-tuples are also considered in human chromosomes 21 and 22, and different behaviors are found in the percentage of four nucleotides. Frequency of appearance of n-tuple f(r) as a function of rank r is also examined. We find the n-tuple Zipf plot shows a power-law behavior for r < 4n−1 and a rapid decrease for r > 4n−1. In order to explore the interior statistical properties of human chromosomes 21 and 22 in detail, we divide the chromosome sequence into some moving windows and we discuss the percentage of ξη (ξ, η = A, C, G, T) pair in those moving windows. In some particular regions, there are some obvious changes in the percentage of ξη pair, and there maybe exist functional differences. The normalized number of repeats N0(l) can be described by a power law: N0(l)  lμ. The distance distributions P0(S) between two nucleotides in human chromosomes 21 and 22 are also discussed. A two-order polynomial fit exists in those distance distributions: log P0(S) = a + bS + cS2, and it is quite different from the random sequence.  相似文献   

10.
We comment on traveling wave solutions and rational solutions to the 3+1 dimensional Kadomtsev–Petviashvili (KP) equations: (ut + 6uux + uxxx)x ± 3uyy ± 3uzz = 0. We also show that both of the 3+1 dimensional KP equations do not possess the three-soliton solution. This suggests that none of the 3+1 dimensional KP equations should be integrable, and partially explains why they do not pass the Painlevé test. As by-products, the one-soliton and two-soliton solutions and four classes of specific three-soliton solutions are explicitly presented.  相似文献   

11.
The largest finite subgroup of O(4) is the non-crystallographic Coxeter group W(H4) of order 14,400. Its derived subgroup is the largest finite subgroup W(H4)/Z2 of SO(4) of order 7200. Moreover, up to conjugacy, it has five non-normal maximal subgroups of orders 144, two 240, 400 and 576. Two groups [W(H2) × W(H2)]  Z4 and W(H3) × Z2 possess non-crystallographic structures with orders 400 and 240 respectively. The groups of orders 144, 240 and 576 are the extensions of the Weyl groups of the root systems of SU(3) × SU(3), SU(5) and SO(8) respectively. We represent the maximal subgroups of W(H4) with sets of quaternion pairs acting on the quaternionic root systems.  相似文献   

12.
In this paper we demonstrate new approach that can help in calculation of electrostatic potential of a fractal (self-similar) cluster that is created by a system of charged particles. For this purpose we used the simplified model of a plane dendrite cluster [1] that is generated by a system of the concentric charged rings located in some horizontal plane (see Fig. 2). The radiuses and charges of the system of concentric rings satisfy correspondingly to relationships: rn = r0ξn and en = e0bn, where n determines the number of a current ring. The self-similar structure of the system considered allows to reduce the problem to consideration of the functional equation that similar to the conventional scaling equation. Its solution represents itself the sum of power-low terms of integer order and non-integer power-law term multiplied to a log-periodic function [5], [6]. The appearance of this term was confirmed numerically for internal region of the self-similar cluster (r0  r  rN−1), where r0, rN−1 determine the smallest and the largest radiuses of the limiting rings correspondingly. The results were obtained for homogeneously (b > 0) and heterogeneously (b < 0) charged rings. We expect that this approach allows to consider more complex self-similar structures with different geometries of charge distributions.  相似文献   

13.
《Applied Mathematical Modelling》2014,38(21-22):5149-5159
This paper presents the study on wind and waves interactions at a seawall using a numerical wave channel. The numerical experiments were conducted for wave overtopping of a 1/4 sloping seawall using several conditions of incident waves and wind speeds. The numerical results were verified against laboratory data in a case for wave overtopping without wind effects. The interaction of waves and wind was analyzed in term of mean wave quantities, overtopping rate and variation of wind velocity at some selected locations. The results showed that the overtopping rate was strongly affected by wind and the wind field was also significantly modified by waves. There exists an effective range of wind speed in comparison with the local shallow wave speed at the breaking location, which gives significant effects to the wave overtopping rates. The maximum of wind adjustment coefficient fw for wave overtopping rate was strongly related to the mean overtopping rate in the case for no wind. This study also showed that when the mean overtopping rate was greater than 5 × 10−4 m3/s/m, the maximum of wind adjustment coefficient fw approached to a specific value of about 1.25.  相似文献   

14.
In this paper, we study the nonlinear dispersive K(m, n) equations: ut + (um)x  (un)xxx = 0 which exhibit solutions with solitary patterns. New exact solitary solutions are found. The two special cases, K(2, 2) and K(3, 3), are chosen to illustrate the concrete features of the decomposition method in K(m, n) equations. The nonlinear equations K(m, n) are studied for two different cases, namely when m = n being odd and even integers. General formulas for the solutions of K(m, n) equations are established.  相似文献   

15.
With the help of invertible linear transformations and the known Lie algebras, a higher-dimensional 6 × 6 matrix Lie algebra (6) is constructed. It follows a type of new loop algebra is presented. By using a (2 + 1)-dimensional partial-differential equation hierarchy we obtain the integrable coupling of the (2 + 1)-dimensional KN integrable hierarchy, then its corresponding Hamiltonian structure is worked out by employing the quadratic-form identity. Furthermore, a higher-dimensional Lie algebra denoted by E, is given by decomposing the Lie algebra (6), then a discrete lattice integrable coupling system is produced. A remarkable feature of the Lie algebras (6) and E is used to directly construct integrable couplings.  相似文献   

16.
We show that the simple matroid PG(n  1, q)\PG(k  1, q), for n  4 and 1  k  n  2, is characterized by a variety of numerical and polynomial invariants. In particular, any matroid that has the same Tutte polynomial as PG(n  1, q)\PG(k  1, q) is isomorphic to PG(n  1, q)\PG(k  1, q).  相似文献   

17.
18.
Let Ay = f, A is a linear operator in a Hilbert space H, y  N(A)  {u : Au = 0}, R(A)  {h : h = Au, u  D(A)} is not closed, ∥fδ  f  δ. Given fδ, one wants to construct uδ such that limδ→0uδ  y = 0. Two versions of discrepancy principles for the DSM (dynamical systems method) for finding the stopping time and calculating the stable solution uδ to the original equation Ay = f are formulated and mathematically justified.  相似文献   

19.
Let n  1 be a fixed integer and let R be an (n + 1)!-torsion free 1-ring with identity element e. If F, d:R  R are two additive mappings satisfying F(xn+1) = F(x)(x1)n + xd(x)(x1)n−1 + x2d(x)(x1)n−2+  +xnd(x) for all x  R, then d is a Jordan 1-derivation and F is a generalized Jordan 1-derivation on R.  相似文献   

20.
《Journal of Complexity》1996,12(2):167-174
LetKbe a closed basic set inRngiven by the polynomial inequalities φ1≥ 0, . . . , φm≥ 0 and let Σ be the semiring generated by the φkand the squares inR[x1, . . . ,xn]. Schmüdgen has shown that ifKis compact then any polynomial function strictly positive onKbelongs to Σ. Easy consequences are (1)f≥ 0 onKif and only iffR++ Σ (Positivstellensatz) and (2) iff≥ 0 onKbutf∈ Σ then asdtends to 0+, in any representation off + das an element of Σ in terms of the φk, the squares and semiring operations, the integerN(d) which is the minimum over all representations of the maximum degree of the summands must become arbitrarily large. A one-dimensional example is analyzed to obtain asymptotic lower and upper bounds of the formcd−1/2N(d) ≤Cd−1/2log (1/d).  相似文献   

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