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941.
The recent results by the PVLAS group on possible changes of polarization of laser light in a transverse magnetic field are beyond the QED expectations by many orders of magnitude. If confirmed, they may indicate new physics associated with ultra-light particles. I describe here how the polarization of light is modified in an external magnetic field by interactions with a spin-zero particle of no definite parity. While the PVLAS-type experiments cannot tell such a particle from one with definite parity, the parity property could be studied in photon regeneration experiments if the polarization of the regenerated photons could be measured. This talk was based on my recent work. 相似文献
942.
R. W. Gothe 《中国物理 C》2009,33(12):1216-1221
The measurements of exclusive single-meson and double-pion electro-production cross sections off the proton to study nucleon resonances will be extended to higher momentum transfers with the CLAS12 detector and the energy upgraded CEBAF beam. Based on new theoretical developments to extract and interpret the electromagnetic transition form factors and on the experience gained from the most recent results, the newly formed collaboration of experimentalists and theorists shall enable us to provide unprecedented high- precision data, high-quality analyses, and state-of-the-art model and QCD based calculations in a Q2 domain up to 10 GeV2. For the first time nucleon resonance structures will be studied at still unexplored distance scales, where the dressed quark contributions are the dominating degrees of freedom and their strong interaction is responsible for the ground and excited nucleon state formation. These studies also open up a promising opportunity to understand the origin of more than 98% of the nucleon mass that is created by strong fields predominantly at these distance scales by dressing the current quarks. 相似文献
943.
假设X是局部凸Hausdorff拓扑向量空间,C是X的闭凸子集,T是一下标集(可以是无限集),假设{ft:t∈T}是一X到R ∪{+∞}的真凸下半连续函数簇,而f:x→R∪{+∞}是一真凸下半连续函数. 相似文献
944.
王学武 《数学的实践与认识》2009,39(10)
在没有独立性、平稳性和相依性假设的条件下,利用分析方法讨论了整值随机变量序列取某个数值的次数与随机变量序列取该数值的条件概率和的等价性问题,建立并证明了若干强极限定理. 相似文献
945.
In this article we extend the work on strongly p-embedded subgroups in Parker and Stroth (Strongly p-embedded subgroups, arxiv:0901.0805) to include the Lie type groups of rank 2. 相似文献
946.
Strong Convergence Analysis of Split-Step θ-Scheme for Nonlinear Stochastic Differential Equations with Jumps 下载免费PDF全文
Xu Yang & Weidong Zhao 《advances in applied mathematics and mechanics.》2016,8(6):1004-1022
In this paper, we investigate the mean-square convergence of the split-step
θ-scheme for nonlinear stochastic differential equations with jumps. Under some standard
assumptions, we rigorously prove that the strong rate of convergence of the split-step
θ-scheme in strong sense is one half. Some numerical experiments are carried out
to assert our theoretical result. 相似文献
947.
Dong-Sheng Guo Chao Yu Jingtao Zhang Ju Gao Zhi-Wei Sun Zhenrong Sun 《Frontiers of Physics》2015,10(2):103201
The currently well accepted cutoff law for laser induced high harmonic spectra predicts the cutoff energy as a linear combination of two interaction energies, the ponderomotive energy Up and the atomic biding energy Ip, with coefficients 3.17 and 1.32, respectively. Even though, this law has been there for twenty years or so, the background information for these two constants, such as how they relate to fundamental physics and mathematics constants, is still unknown. This simple fact, keeps this cutoff law remaining as an empirical one. Based on the cutoff property of Bessel functions and the Einstein photoelectric law in the multiphoton case, we show these two coefficients are algebraic constants, 9 - 4 2 ≈ 3.34 and 2 2 - 1 ≈ 1.83, respectively. A recent spectra calculation and an experimental measurement support the new cutoff law. 相似文献
948.
In this paper, we characterize the saturation of four universal inequalities in quantum information theory, including a variant version of strong subadditivity inequality for von Neumann entropy, the coherent information inequality, the Holevo quantity, and average entropy inequalities. These results shed new light on quantum information inequalities. 相似文献
949.
According to a new electron screening theory,we discuss the beta decay rates of nuclide 56Fe,56Co,56Ni,56Mn,56Cr and 56V with and without strong electron screening (SES).The results show that SES has only a slight effect on the beta decay rates for ρ/μe 108 g/cm3.However the beta decay rates would be influenced greatly for ρ/μe 108 g/cm3.Due to SES,the maximum values of the C-factor (in %) on beta decay rates of 56Fe,56Co,56Ni,56Mn,56Cr and 56V is of the order of 95.03%,35.02%,98.05%,80.33%,98.30% and 98.71% at T9 = 4.0 and 98.83%,98.89%,99.65%,10.32%,4.10% and 40.21% at T9 = 7.0,respectively. 相似文献
950.
The realization of the strong coupling regime is requisite for implementing quantum information tasks. Here, a method for enhancing the atom–field coupling in highly dissipative coupled cavities is proposed. By introducing parametric squeezing into the primary cavity, which is only virtually excited under specific parametric conditions, coupling enhancement between the atom and the auxiliary cavity is realized for appropriate squeezing parameters. This enables the system to be robust against large cavity decay and atomic spontaneous emission. The observation of vacuum Rabi oscillations show that the originally weakly coupled system can be enhanced into an effective strong coupling regime. 相似文献