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1.
In topcolor-assisted multiscale technicolor (TOPCMTC) model.we calculate the corrections of Pseudo Goldstone bosons (technipions,top-pions)to the cross section of the process qq→tt at the Fermilab Tevatron.Our results show that the corrections mainly come form top pions.With reasonable value of the parameters.the correction can increase the total tt production corss section σtt by as much as 17%.This may provide a window to detect tpo-pions.  相似文献   

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We introduce an enhanced multiscale analysis that yields subexponentially decaying probabilities for bad events. For quantum and classical waves in random media, we obtain exponential decay for the resolvent of the corresponding random operators in boxes of side L with probability higher than 1 − e L ζ, for any 0<ζ<1. The starting hypothesis for the enhanced multiscale analysis only requires the verification of polynomial decay of the finite volume resolvent, at some sufficiently large scale, with probability bigger than 1 − (d is the dimension). Note that from the same starting hypothesis we get conclusions that are valid for any 0 < ζ < 1. This is achieved by the repeated use of a bootstrap argument. As an application, we use a generalized eigenfunction expansion to obtain strong dynamical localization of any order in the Hilbert–Schmidt norm, and better estimates on the behavior of the eigenfunctions. Received: 29 November 2000 / Accepted: 21 June 2001  相似文献   

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A new multiscale simulation approach is introduced that couples atomistic-scale simulations using molecular dynamics (MD) with continuum-scale simulations using the recently developed material point method (MPM). In MPM, material continuum is represented by a finite collection of material points carrying all relevant physical characteristics, such as mass, acceleration, velocity, strain and stress. The use of material points at the continuum level provides a natural connection with the atoms in the lattice at the atomistic scale. A hierarchical mesh refinement technique in MPM is presented to scale down the continuum level to the atomistic level, so that material points at the fine level in MPM are allowed to directly couple with the atoms in MD. A one-to-one correspondence of MD atoms and MPM points is used in the transition region and non-local elastic theory is used to assure compatibility between MD and MPM regions, so that seamless coupling between MD and MPM can be accomplished. A silicon single crystal under uniaxial tension is used in demonstrating the viability of the technique. A Tersoff-type, three-body potential was used in the MD simulations. The coupled MD/MPM simulations show that silicon under nanometric tension experiences, with increasing elongation in elasticity, dislocation generation and plasticity by slip, void formation and propagation, formation of amorphous structure, necking, and final rupture. Results are presented in terms of stress–strain relationships at several strain rates, as well as the rate dependence of uniaxial material properties. This new multiscale computational method has potential for use in cases where a detailed atomistic-level analysis is necessary in localized spatially separated regions whereas continuum mechanics is adequate in the rest of the material.  相似文献   

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The multiscale entropy (MSE) reveals the intrinsic multiple scales in the complexity of physical and physiological signals, which are usually featured by heavy-tailed distributions. However, most research results are pure experimental search. Recently, Costa et al. have made the first attempt to present the theoretical basis of MSE, but it only supports the Gaussian distribution [Phys Rev. E 71 (2005) 021906]. We present the theoretical basis of MSE under the inverse Gaussian distribution, a typical model for physiological, physical and financial data sets. The analysis allows for uncorrelated inverse Gaussian process and 1/f noise with the multivariate inverse Gaussian distribution, and then provides a reliable foundation for the potential applications of MSE to explore complev nhwical and Dhwical time series.  相似文献   

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在多标度人工色模型框架下计算了荷电PG玻色子π±1和π±8对K介子稀有衰变过程K+→π+νν,KL→π0νν和KL→μ+μ的企鹅图贡献.计算结果表明:(a)荷电PG玻色子可以对K介子稀有衰变分枝比给出1~3个量级的增强;(b)根据现有实验数据,K.Lane等人提出的多标度人工色模型基本被排除.  相似文献   

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在多标度人工色模型框架下计算了荷电PG玻色子  相似文献   

9.
A method is introduced for simulating long timescale macromolecular structural fluctuations and transitions with atomic-scale detail. The N-atom Liouville equation for the macromolecule/host medium system provides the starting point for the analysis. Order parameters characterizing overall macromolecular architecture are demonstrated to be slowly evolving. For single-stranded macromolecules, a curvilinear coordinate provides a way to introduce the order parameters. Using a multiscale approach, Fokker–Planck equations are derived. A nanocanonical method for constructing the lowest order solution to the Liouville equation and the equivalence of long-time and ensemble averages avoid the tedious bookkeeping needed to preserve the number of degrees of freedom (required in earlier methods). The method overcomes the large energy barriers that plague other approaches for estimating rates of transition between macromolecular conformations. A reduced dynamics is derived for the friction dominated limit. New experimental methods for observing macromolecular dynamics and medical sciences applications are discussed.  相似文献   

10.
We calculated the Pseudo-Goldstone bosons (technipions, top-pious) corrections to the cross-section a of the process e+e→bs in topcolor-assisted multiscale technicolor model at LEP Ⅱ energy region. Our results show that, with reasonable value of the parameters, the cross-section is one order larger than that predicted by the standard model. We discussed the possibility of detecting this rare event at the B-factoly.  相似文献   

11.
研究Multiscale Walking Technicolor模型(MWTCM)中赝标戈尔斯通玻色子(PGB)对b→sγ分支比的修正,发现修正太大以致很难解释最近CLEO的实验数据,如果进一步引入Topcolor,在Topcolor assistedMWTCM中,BR(b→sγ)在参数的一定空间内同CLEO的实验数据一致.  相似文献   

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We review recent results on the relations between classical solutions of nonlinear-models and Toda equations, and point out some relations among Toda equations (two-dimensions), the continuum Toda equation (three-dimensions), and self-dual Einstein equations (four-dimensions).Partially supported by the Grant-in-Aid for Scientific Research, No. 04640088.  相似文献   

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A set of analytical and computational tools based on transition path theory (TPT) is proposed to analyze flows in complex networks. Specifically, TPT is used to study the statistical properties of the reactive trajectories by which transitions occur between specific groups of nodes on the network. Sampling tools are built upon the outputs of TPT that allow to generate these reactive trajectories directly, or even transition paths that travel from one group of nodes to the other without making any detour and carry the same probability current as the reactive trajectories. These objects permit to characterize the mechanism of the transitions, for example by quantifying the width of the tubes by which these transitions occur, the location and distribution of their dynamical bottlenecks, etc. These tools are applied to a network modeling the dynamics of the Lennard–Jones cluster with 38 atoms ( \(\mathrm{LJ}_{38}\) ) and used to understand the mechanism by which this cluster rearranges itself between its two most likely states at various temperatures.  相似文献   

15.
Galileo found the Copernican heliocentric theory of the universe so persuasive owing to its mathematical elegance that he embraced it even when his theory of the tides stood in opposition to it. Further support for Galileo’s deep commitment to the Copernican heliocentric theory is found in his recently discovered unpublished observations of the double star Mizar in 1617, which exhibited no annual stellar parallax and hence indicated that the Earth does not move, in contradiction to the Copernican heliocentric theory. Further, Galileo did not mention this contradiction in his Dialogue Concerning the Two Chief World Systems of 1632. I conclude that he was so deeply committed to the Copernican heliocentric theory that he was unswayed even when observations undermined it, and I suggest that if he had published his observations on the double star Mizar, general acceptance of the Copernican heliocentric theory by astronomers would have been delayed even more than it was. Christopher M. Graney teaches physics and astronomy at Jefferson Community College in Louisville, Kentucky, and runs the college’s observatory at Otter Creek Park in Louisville.  相似文献   

16.
A novel approach has been made to the divergence problem in local field theories, in which the notion of locality is still retained but loses its absolute meaning, just like simultaneity. The basic idea is to introduce a pure-imaginary elementary length into 3-dimensional space, while keeping time structureless so as to retain the unitarity of theS-matrix. Consequently, light becomes dispersive at sufficiently short wavelengths, and Lorentz transformation becomes a point-to-string transformation. When reformulated to meet the new Lorentz invariance, all the localfield (in the above sense) theories in a flat space become finite,while retaining their conventional form. This has been demonstrated by the derivation of finitized Coulomb potential and correct high-momentum behavior of quantum-electrodynamic coupling constant. For diagrams including gravitons, evaluation of the superficial degrees of divergence shows that only a restricted number of 1-(and 2-) loop diagrams might be divergent, while those of more than 3 loops are definitely convergent, thus indicating possible renormalizability (or something better) of quantum gravity in Einstein's formalism of general relativity. Since 4-dimensional simple supergravity removes 1-and 2-loop divergence, a combination of the theory and the present one might lead to a more interesting result.  相似文献   

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It is shown that the before-before (or Suarez-Scarani) experiment refutes hidden variable models with a deterministic (“realistic”) nonlocal part, whereas experiments violating Leggett-type inequalities refute models with biased random local part. Therefore the claim that Gröblacher et al. (Nature 446:871–875, 2007) present “an experimental test of nonlocal realism” is misleading, and Marek ?ukowski’s (Found. Phys. 38:1070, 2008) comment misses the point. A new experiment is suggested.  相似文献   

19.
AuthorIndextoVolumeB3,1994Alda,J.--(3),265GuoHong--(2),129,137;(4),317;(5),421;Bernabeu,E.--(3),265(6),529,533CatShangda--(4)...  相似文献   

20.
h,Jintao一(3),193 h,Jinxing—(2),97 Fan,Haming一(6)石21Chen,Chungtian(l),33 Fan,Pinzhong、(3),229;(6),509Ch*n,**-g-fang一(),39Fel,Lin一(2),139;(5),447Ch*n,F.一(6),533 F*正oher,A.一(6),549Chen,Fang(5),409 Fu,C.H.(5),455Chen,Gaoting(5),385 Fu,Iyung(6),497Chen,Hongbin、(5),399 Fu,Sizu、(6),481C卜*n,H***s*h*一(6),557 Fu,Y***ha*s一(2)J89Chen,Jianwen一(1),71 Fu,Zuliang一(4),289Chen,Jinfeng一(豆),91 Gan,Fuxi一(正),67Chen,Jinkai一(2),155 Gao,Junyi一(5),393,399;(6)石03Chen,S.C.一(l),6…  相似文献   

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