从大数假设到人择宇宙学原理

 我们知道,在物理量中有不少是物理常量,这些物理常量可分为两类。一类是物理常量,和物理性质有关,如比热、电阻率、折射率等,这些常量在一定条件下会随某一因素而改变;另一类是基本物理常量,是物理学中的普适常量,如真空中的光速c、引力常量G、普朗克常量h,等等。对这些基本物理常量的测定和研究在物理学的发展中占有重要地位。由于现代物理理论所依据的基本假设是这些物理常量的不变性,因此大量的物理实验都是围绕这些基本物理常量进行的。另外基本物理常量间的协调还是检验物理理论的重要途径,因而一直受到人们的高度重视。     

基本物理常量的最新数值——现代计量科学专题之四

现代量子计量基准的量值建立在基本物理常量的基础之上,因此达到了极高的稳定性和复现性。而基本物理常量数值的精确测定也依赖于现代计量技术。因此在20世纪后半叶,物理学和计量学建立了极为密切的关系。国际物理和化学常量委员会特别成立了一个由物理学家和计量学家联合组成的基本物理常量任务组,收集各国在最精密的基本物理常量测量工作方面的最新进展,并进行“基本物理常量的平差工作”,得到基本物理常量的最新数值。     

基本物理常数评定的新进展

本文回顾了基本物理常数的评定工作，对１９７３年和１９８６年的推荐值作了比较，并着重介绍里德堡常数、阿佛加德罗常数的测定史和量子霍耳效应对基本物理常数的重要影响，最后讨论了基本物理常数的发展趋势．     

三届基本物理常数CODATA平差综述

评述了最近三届基本物理常数CODATA(1998,2002,2006)推荐值,阐述了各阶段所依据的主要实验及理论上的新进展,介绍了三个实验新技术对物理常数发展的特殊作用.     

基本物理常数和它的最小二乘法平差

本文简述了基本物理常数的重要意义，介绍基本常数最小二乘法平差的工作要点及常数推荐值的产生过程．     

基本物理常量与国际单位制基本单位的重新定义

用固定若干基本物理常量的数值重新定义国际单位制基本单位，可以大幅度提高基本单位的准确性。     

基本物理常数概述及牛顿引力常数的测量

据不完全统计,基本物理常数有160余个之多,覆盖物理学各个领域。自国际科学技术数据委员会(CODATA)1973年首次发表国际推荐值以来,至今已发表了6次推荐值。文章介绍了基本物理常数的分类以及近期发表的基本物理常数领域的主要成就。这些成就及新的突破对物理学和计量学具有重要的意义。牛顿引力常数是测量万有引力的重要常数,具有深远的意义,但其数值极小,因此测量难度很大;二百余年来,科学家精益求精,不断更新方法,以求减小其测量的不确定度。     

耐人寻味的物理常量

 如果说钢琴、小提琴、马头琴等乐器能为我们奏响美妙动听的音乐,那么,在研究物理学的过程中,我们围绕一些物理常量,能够讲述许多有趣动人的故事。它们的问世,为物理理论建立创造了最基本的前提条件。物理学中有许多常量。回顾一下物理学发展史,从经典物理到现代物理,从普通物理到理论物理,最引人注目的物理常量是重力加速度g、玻耳兹曼常数k、真空中的光速c、普朗克常数h。它们在揭示物理现象及其规律,建立物理理论过程中都具有划时代的意义。     

探讨大学物理实验教学中物理常量的使用和测量结果的表示

指出并探讨当前大学物理实验教学尚存部分内容陈旧落后、与科学技术发展脱节以及是否采用国际、国家通用标准等问题.通过介绍基本物理常量的研究进展,建议在教学中采用国际科学技术数据委员会2006年推荐的基本物理常量;根据国内外学术惯例及国家标准,提出测量结果不确定度的表示方法;为避免有效数字缺乏统一的定义或引起误解,建议在实验教学中用修约间隔规定后的修约值来代替有效位数的概念,同时要引入修约间隔的概念;最后,给出了微小标准差的可忽略准则.     

SI基本单位的研究进展与改制动向

文章介绍了SI（国际单位制）基本单位的研究进展与改制动向，综述了实现质量、电流与温度单位自然基准的主要方法，展望了用基本物理常量重新定义SI基本单位的前景及对物理学研究的影响。     

Fundamental physical constants: Input data and recommended values by CODATA 2002

The CODATA recommended values of the fundamental physical constants are the most accurate and most reliable constant values applied in different branches of physics. Various questions related to recommendations are considered.     

基本物理常数最新推荐值评述

简明地评述了由国际科学技术数据委员会（CODATA）1998年推荐的基本物理常数中得到的一些结论,按CODATA两次推荐的数值,对1998年和1986年的常数值及相应的不确定度进行了比较,并讨论常烽值的变化对物理学和计量学的影响。     

Spectroscopy of antiprotonic helium atoms and its contribution to the fundamental physical constants

Antiprotonic helium atom, a metastable neutral system consisting of an antiproton, an electron and a helium nucleus, was serendipitously discovered, and has been studied at CERN’s antiproton decelerator facility. Its transition frequencies have recently been measured to nine digits of precision by laser spectroscopy. By comparing these experimental results with three-body QED calculations, the antiproton-to-electron massratio was determined as 1836.152674(5). This result contributed to the CODATA recommended values of the fundamental physical constants.     

Adjusted recommended values of the fundamental physical constants

A brief overview of the CODATA-2006 adjustment (P.J. Mohr, B.N. Taylor, and D.B. Newell, CODATA Recommended values of the fundamental physical constants: 2006, Rev. Mod. Phys. 80, (2008) 633) is presented. The attention is focussed on the most important data that appeared since the previous adjustment in 2002, and on changes in the recommended values of 2006 in comparison with the results of 2002. We consider a structure of the input data and their correlations and analyze the results and the data group by group. We also discuss consequences of the adjustment.     

Accurate Determination of the Values of Fundamental Physical Constants: The Basis of the New “Quantum” SI Units

The metric system appeared as the system of units designed for macroscopic (laboratory scale) measurements. The progress in accurate determination of the values of quantum constants (such as the Planck constant) in SI units shows that the capabilities in high-precision measurement of microscopic and macroscopic quantities in terms of the same units have increased substantially recently. At the same time, relative microscopic measurements (for example, the comparison of atomic transition frequencies or atomic masses) are often much more accurate than relative measurements of macroscopic quantities. This is the basis for the strategy to define units in microscopic phenomena and then use them on the laboratory scale, which plays a crucial role in practical methodological applications determined by everyday life and technologies.The international CODATA task group on fundamental constants regularly performs an overall analysis of the precision world data (the so-called Adjustment of the Fundamental Constants) and publishes their recommended values. The most recent evaluation was based on the data published by the end of 2014; here, we review the corresponding data and results. The accuracy in determination of the Boltzmann constant has increased, the consistency of the data on determination of the Planck constant has improved; it is these two dimensional constants that will be used in near future as the basis for the new definition of the kelvin and kilogram, respectively. The contradictions in determination of the Rydberg constant and the proton charge radius remain. The accuracy of determination of the fine structure constant and relative atomic weight of the electron has improved.Overall, we give a detailed review of the state of the art in precision determination of the values of fundamental constants. The mathematical procedure of the Adjustment, the new data and results are considered in detail. The limitations due to macroscopic properties of material standards (such as the International prototype of the kilogram) and the isotopic composition of substances involved in precision studies in general (as standard measures for the triple point of water) and, in particular, in the determination of the fundamental constants are discussed. The perspectives of the introduction of the new quantum units, which will be free from the mentioned problems, are considered.Many physicists feel no sympathy for the International system of units (SI), believing that it does not properly reflect the character of physical laws. In fact, there are three parallel systems, namely the systems of quantities, system of their units and the related standards. The definition of the units, in particular, the SI units, above all, reflects our ability to perform precision measurements of physical values under certain conditions, in particular, to create appropriate standards. This requirement is not related to the beauty of fundamental laws of nature. More accurate determination of the fundamental constants is one of the areas where we accumulate such experience.     

Determination of the gravitational constant G

A precise knowledge of the Newtonian gravitational constant G has an important role in physics and is of considerable meteorological interest. Although G was the first physical constant to be introduced and measured in the history of science, it is still the least precisely determined of all the fundamental constants of nature. The 2002 CODATA recommended value for G, G = (6.6742 ± 0.0010) × 10⁻¹¹m³ · kg⁻¹ · s⁻², has an uncertainty of 150 parts per million (ppm), much larger than that of all other fundamental constants. Reviewed here is the status of our knowledge of the absolute value of G, methods for determining G, and recent high precision experiments for determining G.     

Gas phase vibrational fundamentals and vib-rotational parameters of AsCl3

Contour simulation of the gas phase infrared fundamental bands of AsCl₃ led to estimated values for the first-order Coriolis constants, the vibrational frequencies, and the relative values of the vibrational transition moments. Improved values of the six independent force constants of a general quadratic force field were determined on the basis of the observed frequencies, mean amplitudes of vibration, and Coriolis and centrifugal distortion constants. The potential energy distribution over the normal modes is reported.     

谈普朗克质量

简要介绍了普朗克于1912年提出的三个基本物理量：普朗克质量、普朗克长度和普朗克时间，它们巳被列入1986和1998年基本物理常数表，该文只讨论普朗克质量，假定原子核内存在量子化的核力场，命名其场量子为“引斥子”，其质量推算出恰好等于普朗克质量，由此可用4个耦合常数定量地描述四种相互作用的强度比，从而还可找到一种测定G的新方法。     

PO2自由基的光谱常数和非谐力场的理论研究

利用B3PW91、B3LYP和B3P86方法以及cc-pvQz和6-311++G(3df,3pd)基组计算了PO2自由基的光谱常数。先将计算的平衡几何结构、转动常数、谐频和基频、四次离心畸变常数和六次离心畸变常数与已有的相应实验或理论数据进行了比较。在此基础上,从理论上预测了非谐性常数、振转相互作用常数、科里奥利耦合常数、三次和四次力常数。计算结果表明,B3PW91/G理论水平得到的PO2自由基的光谱常数是可靠的。