Probability Collectives for Unstable Particles

Unstable particles, together with their stable decay products, constitute probability collectives that are defined as Hilbert spaces with dimension higher than one, nondecomposable in a particle basis. Their structure is considered in the framework of Birkhoff-von Neumann's Hilbert subspace lattices. Bases with particle states are related to bases with a diagonal scalar product by a Hilbert-bein involving the characteristic decay parameters (in some analogy to the n-bein structures of metrical manifolds). Probability predictions as expectation values, involving unstable particles, have to take into account all members of the higher dimensional collective. For example, the unitarity structure of the S-matrix for an unstable particle collective can be established by a transformation with its Hilbert-bein.     

A probabilistic method for analysis of sound localization performance

We propose a novel probabilistic method for quantitative analysis of the sound localization performance. The analysis is based on the two kinds of probability distributions estimated from a single dataset containing listening test results for sound localization. The quantitative parameters of the von Mises probability distributions provide meaningful interpretations on the localization performance. The mean direction represents the listener’s perceptual bias, and the shape parameters and the circular variance provide information on how much the responses are concentrated about the mean direction. The front-back confusion can be determined more systematically by the proposed method than the conventional one, especially for the responses near the boundary of front-back confusion region based on the conventional criterion. The proposed method can be easily extended to analyze the up-down and left-right confusions. To investigate the feasibility of the proposed method, the already published dataset originally obtained by Iida et al. was analyzed using the proposed probabilistic method. The results showed that the proposed method can provide meaningful and reasonable interpretations on the localization performance.     

论证式教学在高中物理概念课中的应用策略

构建论证式教学模式及流程,着力搭建联系物理概念课教学与培养学生科学论证能力之间的“桥梁”,文章从营造论证氛围、显化论证语言、丰富论证资料、提升论证能力4个维度阐述在物理概念课上进行论证式教学的策略.     

Ensemble interpretation of the EPR-Bell correlations

The EPR-Bell correlations between the spins of a pair of particles originally in a singlet state are discussed both on the basis of the mathematical formalism of quantum mechanics and the ensemble interpretation. It is shown that the correlations predicted by the mathematical formalism are in agreement with those expected on the basis of the ensemble interpretation, if the electrons are treated as distinguishable particles after they separate and undergo observation. In this case, the correlations are only in partial agreement with agedanken experiment of Mermin on the subject. It is pointed out, however, that agreement with Mermin’s conclusions is possible if one treats the electrons as indistinguishable even when they are subjected to observation after separation, though there is no obvious theoretical justification for doing so.     

Attempt to Resolve the EPR-Bell Paradox via Reichenbach's Concept of Common Cause

Reichenbach's common cause principle claims that if there is correlation betweentwo events and none of them is directly causally influenced by the other, thenthere must exist a third event that can, as a common cause, account for thecorrelation. The EPR-Bell paradox consists in the problem that we observecorrelations between spatially separated events in the EPR experiments whichdo not admit common-cause-type explanation, and it must therefore be concludedthat, contrary to relativity theory, in the realm of quantum physics there existsaction at a distance, or at least superluminal causal propagation is possible; thatis, either relativity theory or Reichenbach's common cause principle fails.By means of closer analyses of the concept of common cause and a more precisereformulation of the EPR experimental scenario, I sharpen the conclusion wecan draw from the violation of Bell's inequalities.     

Relative Frequency and Probability in the Everett Interpretation of Heisenberg-Picture Quantum Mechanics

The existence of probability in the sense of the frequency interpretation, i.e., probability as long term relative frequency, is shown to follow from the dynamics and the interpretational rules of Everett quantum mechanics in the Heisenberg picture. This proof is free of the difficulties encountered in applying to the Everett interpretation previous results regarding relative frequency and probability in quantum mechanics. The ontology of the Everett interpretation in the Heisenberg picture is also discussed.     

Frequency dependence of junction capacitance of BPW34 and BPW41 p-i-n photodiodes

This article investigates the frequency dependence of small-signal capacitance of silicon BPW34 and BPW41 (Vishay) p-i-n photodiodes. We show that the capacitance-frequency characteristics of these photodiodes are well-described by the Schibli and Milnes model. The activation energy and the concentration of the dominant trap levels detected in BPW34 and BPW41 are 280–330 meV and 1.1×10¹²−1.2×10¹² cm⁻³, respectively. According to the high-frequency C-V measurements, the impurity concentrations are determined to be about 5.3×10¹² and 1.9×10¹³ cm⁻³ in BPW41 and BPW34, respectively using the method of ΔV/Δ(C ⁻²) vs. C.      

Frequency and size distribution dependence of visible and infrared extinction for astronomical silicate and graphite grains

In a recent paper, the frequency and size distribution dependence of extinction spectra for astronomical silicate and graphite grains was analyzed in the context of MRN type interstellar dust models in the far ultraviolet and ultraviolet regions. These grains were taken to be homogeneous spheres following a power law size distribution. In the present work we extend the analysis further to cover the visible as well as the infrared part of the electromagnetic spectrum. The analytic formulas presented here along with those given in the earlier paper would enable one to evaluate extinction for these grains within a wider wavelength range 1000-22,500 Å and analyze the observational interstellar extinction data in far greater details.     

Free probability and the von Neumann algebrasof free groups

This short note summarizes the circumstances of the birth of free probability theory andsome of the recent achievements.     

激光频率调制线型分析

在激光频率调制的理论分析中,一般采用正弦波调制、正弦波解调,而没有讨论调制和解调的其它情况。本文主要分析了Guass线型吸收的情况下,锯齿波调制、方波解调的一次、二次谐波相检结果和三角波调制、方波解调的一次、二次谐波相检结果,以及调制深度对信号谱形和信号强度的影响。我们发现,在锯齿波调制、方波解调情况下,一次、二次谐波谱形和正弦波调制情况区别很大;但在三角波调制、方波解调情况下,可以获得和正弦波调制、正弦波解市场相似的结论。另外,不同的调制深度对输出的调制谱形也有重要的影响。我们还用甲烷的可调谐 红外光调制吸收光谱实验验证了理论分析结果。最终得到结论：频率调制谱的信号谱形及信号强度与调制波形、解调波形和调制深度均有关系。     

量子条件振幅算子性质的研究

分析量子条件振幅算子的性质,该算子起一个类似于在经典信息理论中的条件概率的作用.论证表示一个量子双组元系统的条件算子的频谱在局域幺正变换下是不变的,并且表明它的不可分性.证明一个可分态的条件振幅算子不能有一个超过1的本征值.得出一个在von Neumann条件熵的非负性基础上的相关的可分性条件.关键词：条件概率条件振幅算子von Neumann条件熵可分性条件     

Frequency dependence of AC loss in Bi(2223)Ag-sheathed tapes

The AC self-field loss in Bi(2223)Ag-sheathed tapes with different number of filaments has been measured between 59 and 2500 Hz by means of a dual lock-in amplifier. Due to the wide frequency range of the measurements, we have been able to dissociate quantitatively the different self-field loss contributions: hysteretic, eddy current and resistive loss (near I_c). This is an important advantage compared to single frequency measurements where such loss dissociation is only qualitative. The hysteresis losses of the different tapes fall between Norris' predictions for elliptical and strip cross-section. The relative weight of eddy current loss is found to be inversely proportional to the current ratio—the higher the i, the less is their contribution. Frequency-independent resistive loss due to flux-creep is observed for high currents at low frequencies; this loss becomes quickly negligible with the increasing frequency.     

Frequency dependence of the surface states at the N-type Si-SiO2 interface

The response of the surface states at then-type Si-SiO₂ interface to the different a.c. signal frequencies has been studied. The response values have been computed from both the measured capacitance voltage (C-V) and conductance-voltage (G-V) techniques. The results presented show that the frequency response of the effective density of states to different a.c. signal frequencies is proportional to the log of the applied frequencies.     

积累检测在光电设备中的应用分析

有些光电检测设备要求高的探测概率和低的虚警概率,使用单次检测不能达到要求。若采用积累榆测法则能满足系统要求。通过对积累检测在不同类型光电设备中的应用分析,建立了不同的数学模型,推导出各模型的探测概率和虚警概率的计算公式,并给出了相应的计算结果。计算结果表明：积累检测在主动探测设备中使用不连续的“K out of N”模型,能够有效提高探测概率,降低虚警概率。但在被动探测设备中,探测概率有所卜降,虚警概率会大大降低。     

Dependence Analysis of the Solutions on the Parameters of Fractional Delay Differential Equations

In this paper, we investigate the dependence of the solutions on the parameters (order, initial function, right-hand function) of fractional delay differential equations (FDDEs) with the Caputo fractional derivative. Some results including an estimate of the solutions of FDDEs are given respectively. Theoretical results are verified by some numerical examples.     

Theoretical Analysis of the Frequency Jump in E-fishbone Experiments

It is identified that barely passing electrons are the drive of the e-Gshbones,rather than the barely trapped electrons at low frequency.The frequency jump in e-Bshbone experiments is reproduced and analyzed.It is found that the e-Bshbone frequency increases with the hot electron energy,which is consistent with the experiments.The growth rate of the mode(m = 2,n = 2) is greater than that of the mode(m = 1,n = 1).     

外光电效应中零电场光电流与入射光频率关系的实验研究

分析了现有理论推导出的光电流与入射光频率定量关系,用普朗克常数测定仪实测了反向遏制电压为(零电场)时Ag-O-K光电管光电流在不同频率但相同光强作用下随入射光频率变化的曲线,并与理论推导的结论进行了比对和讨论分析。     

热声驱动器谐振频率影响因素分析

分析了结构参数、操作参数以及工质等因素对热声驱动器谐振频率的影响 ,并结合驻波型热声驱动器 ,给出了相应的计算结果和实验数据。