宇宙学研究的盛宴已过?——评述2019年诺贝尔物理学奖

2019年诺贝尔物理学奖授予美国普林斯顿大学James Peebles(詹姆斯·皮伯斯)教授和瑞士日内瓦大学的Michel Mayor(米歇尔·梅耶)教授和瑞士日内瓦大学教授兼英国剑桥大学教授Didier Queloz(迪迪埃·奎洛兹)以表彰他们的研究对于我们理解宇宙的演化和地球在宇宙中的位置做出了巨大贡献.基于此本文评述了诺贝尔物理学奖授予他们分别在宇宙学和系外行星方面的重要贡献,今年诺奖颁发的新特点.     

1994年诺贝尔物理学奖

 据瑞典皇家科学院信息部10月12日提供的信息,瑞典皇家科学院已将1994年诺贝尔物理学奖授予利用中子散射技术来研究凝聚态物质作出先驱贡献的两位学者:一位是为中子谱学发展作出贡献的加拿大安大略省哈密尔顿-麦克马斯特大学的布罗克豪斯(Bertram N.Brockhouse)教授,另一位是为中子绕射技术作出贡献的美国麻省剑桥麻省理工学院的沙尔(Clifiord G.Shull)教授。本文将对他们的贡献作简单的介绍。     

中国光学学会副理事长王之江教授作为第一位中国学者被授予美国光学学会特别会员(Fellow)荣誉称号

1988年7月25日在上海天马大酒店’88国际激光材料与激光光谱专题会议的招待会上,由美国光学学会主席W.B.Bridges教授授予王之江教授美国光学学会特别会员的荣誉称号并授予证书.美国光学学会特别会员须由五名以上有名望的科学家的荐书,授予那些在光学和激光领域中作出显著贡献的科学家,其数额为美国光学学会正式会员总数的十分之一.王之江教授是美国光学学会正式会员,他由美国光学和激光界著名科学家Tingye Li、A.L.Shawlow、A.J.Glass、H.J.Caulfietd、C.P.     

光的量子相干性与光频率的超精密测量--2005年诺贝尔物理学奖评述

2005年的诺贝尔物理学奖授予了现代光学领域的科学家，其中诺贝尔奖的一半授予了哈佛大学的Roy J．Glauber教授，以表彰他在光的量子相干性理论方面的突出贡献，诺贝尔奖的另外一半授予了美国科罗拉多大学与美国国家标准技术研究院联合实验（JILA）的John L．Hall教授和德国慕尼黑大学教授、马克斯普朗克-量子光学研究所所长TheodorW．Hansch教授，以表彰他们在光的超高精密测量方面的突出贡献，文章介绍了三位诺贝奖得主的贡献及其意义．     

景云教授荣获美国声学学会林德希奖章

正2018年5月美国声学学会175届年会颁奖典礼上,美国北卡州立大学(NCSU)机械与航空系景云教授被授于林德希奖章(R.Bruce Lindsay Medal)。这是美国声学学会为表彰声学界有重要贡献的中青年学者而设立的荣誉奖章。自1942年设立该奖以来,景云教授是首位获得该奖章的由中国大陆成长的华人科学家。此前得该奖章后并成为声学名家的有如L.Beranek,D.M.Green,R.E.Apfel,L.R.Rabiner,M.F.Hamilton等人。景云教授十几年来在室内空间声场、声波方程数值计算、非线性声学、声学超材料以及超表面等研究     

多铁性材料:过去、现在、未来

2010年美国物理学会的James C.MeGroddy奖授予了三位美国科学家:加州大学圣芭芭拉分校Nicola A.Spaldin教授、罗格斯大学Sang-Wook Cheong教授和加州大学伯克利分校Ramamoorthy Ramesh教授,以表彰他们"在推进对多铁性氧化物的认识以及应用方面所作的奠基性贡献".2010年10月份的Physics Today(2010年第10期,第38-43页)刊登了这三位教授为此撰写的精彩文章,对多铁性材料研究的过去、现在和未来进行了评述与展望.全文主要内容如下:     

非线性光学的光谱学——兼谈布洛姆伯根对发展激光光谱学的贡献

美国哈佛大学N.布洛姆伯根(N.Bloember-gen)教授是1981年诺贝尔物理学奖金三位获得者之一.他的科学成就是多方面的.在核磁共振、固态微波量子放大器(Maser)、电子顺磁共振、激光光谱学以及非线性光学等方面都有突出的贡献。这次被授于诺贝尔奖是为表彰他在发展激光光谱学方面作     

北京大学聘请沈元壤先生担任客座教授

1986年 12月 22日,北京大学校长丁石孙教授把聘请担任客座教授的聘书送给了著名物理学家、美国加利福尼亚州立大学伯克利分校教授沈元壤.沈元壤先生生于上海,在台湾大学毕业后赴美攻读博士学位,是诺贝尔奖金物理学奖获得者、哈佛大学教授Bloem-bergn的学生.沈元壤教授是非线性光学这一新的物理学领域的开拓者之一.他在非线性光学的一系列的基本问题上的贡献是众所周知的.七十年代以来,他致力于利用各种非线性光学效应来研究原子、分子物理和凝聚态物理,取得一系列重要成果,也开辟了一些新的研究领域,特别是近年来他率先开辟了利用非线性光…     

中国著名物理学家——施汝为教授

著名物理学家施汝为教授,1901年11月19日生于上海市崇明县.1925年毕业于南京东吴大学后被聘入清华大学物理系任教,并开始研究磁学.1930年赴美国伊利诺大学攻读学位,1932年获物理学硕士学位.后来转入耶鲁大学继续深造,曾受美国著名物理学家迈吉尔教授指导.1934年完成毕业论     

爱因斯坦的教育观

E．Leonard Jossem教授曾连任三届ICPE（International Commission of Physics Education）的主席，并曾任美国The Ohio State University物理系主任．Jossem教授是我国物理教育界的老朋友，也多次来中国参加各种物理教育交流活动，为中外物理教育方面的交流做出了贡献．为纪念2005世界物理年，Jossem教授在下面的短文中特意汇集了爱因斯坦关于教育方面的一些观点和言论，本刊特此刊登，并向Jossem教授致谢．     

\tau\rightarrow\omegA3\pi\nu decays

A theoretical study of the anomalous decay mode is presented. The theoretical value of the branching ratio of agrees well with the data. The branching ratio of is predicted. It is found that the vertices of and play a dominant role in these two decay modes. CVC is satisfied, and there is no adjustable parameter. Received: 30 July 2001 / Published online: 21 November 2001     

Testing non-commutative QED \gamma\gamma\gamma and \gamma\gamma\gamma\gamma couplings at LHC

In this work, we investigate the sensitivity of the process at LHC for the photonic 3- and 4-point functions that appear in non-commutative QED. We show that this process serves to study the behavior of the space-space as well as of the space-time non-commutativity. We also show that this process can probe the non-commutative scale in the range of a few TeV.Received: 9 February 2004, Revised: 27 February 2004, Published online: 8 April 2004     

The process\pi ^0 \to \lambda _\gamma \bar \lambda _\gamma as an alternative to\pi ^0 \to v\bar v

The process \(\pi ^0 \to \lambda _\gamma \bar \lambda _\gamma \) is investigated as an alternative to \(\pi ^0 \to v\bar v\) . It is shown that the experimental bound on the branching fraction for missing energy (in the form of \(\lambda _\gamma \bar \lambda _\gamma \) and/or \(v\bar v\) ) may be understood in terms of \(\pi ^0 \to \lambda _\gamma \bar \lambda _\gamma \) for the kinematically allowed photino mass, if the squark mass is >8 GeV.     

Process $$\gamma \gamma \to \nu \bar \nu$$ in a strong magnetic field

The three-vertex loop amplitude in a strong magnetic field are analyzed in a general form by using the asymptotic behavior of the electron propagator in an external field. The process \(\gamma \gamma \to \nu \bar \nu\) is studied in terms of the scalar-vector-vector (SVV), pseudoscalar-vector-vector (PVV), vector-vector-vector (VVV), and axial-vector-vector-vector (AVV) combinations of couplings. It is shown that only in the case of the SVV combination does the amplitude grow linearly with increasing magnetic-field strength, the amplitudes evaluated with the other combinations of couplings (PVV, VVV, and AVV) featuring no linearly increasing terms. The process \(\gamma \gamma \to \nu \bar \nu\) is also studied within the left-right model, which is an extension of the Standard Model of electroweak interactions and which may involve an effective scalar ννee coupling. Possible astrophysical manifestations of this process are discussed.     

\left\langle {:\bar \psi \psi :} \right\rangle and three-point functions in QCD

We calculate the coefficients of to leading order in _s in the operator product expansion of the fundamental three-point functions of QCD in the deep Euclidean region. We demonstrate that these coefficients satisfy the Ward identities.Supported by BMFT 0233 REB4     

Analyticity of \eta \pi isospin-violating form factors and the \tau \rightarrow \eta \pi \nu second-class decay

We consider the evaluation of the \(\eta \pi \) isospin-violating vector and scalar form factors relying on a systematic application of analyticity and unitarity, combined with chiral expansion results. It is argued that the usual analyticity properties do hold (i.e. no anomalous thresholds are present) in spite of the instability of the \(\eta \) meson in QCD. Unitarity relates the vector form factor to the \(\eta \pi \rightarrow \pi \pi \) amplitude: we exploit progress in formulating and solving the Khuri–Treiman equations for \(\eta \rightarrow 3\pi \) and in experimental measurements of the Dalitz plot parameters to evaluate the shape of the \(\rho \) -meson peak. Observing this peak in the energy distribution of the \(\tau \rightarrow \eta \pi \nu \) decay would be a background-free signature of a second-class amplitude. The scalar form factor is also estimated from a phase dispersive representation using a plausible model for the \(\eta \pi \) elastic scattering \(S\) -wave phase shift and a sum rule constraint in the inelastic region. We indicate how a possibly exotic nature of the \(a_0(980)\) scalar meson manifests itself in a dispersive approach. A remark is finally made on a second-class amplitude in the \(\tau \rightarrow \pi \pi \nu \) decay.     

Dispersion relations for $$\eta '\rightarrow \eta \pi \pi $$

We present a dispersive analysis of the decay amplitude for \(\eta '\rightarrow \eta \pi \pi \) that is based on the fundamental principles of analyticity and unitarity. In this framework, final-state interactions are fully taken into account. Our dispersive representation relies only on input for the \({\pi \pi }\) and \({\pi }\eta \) scattering phase shifts. Isospin symmetry allows us to describe both the charged and neutral decay channel in terms of the same function. The dispersion relation contains subtraction constants that cannot be fixed by unitarity. We determine these parameters by a fit to Dalitz-plot data from the VES and BES-III experiments. We study the prediction of a low-energy theorem and compare the dispersive fit to variants of chiral perturbation theory.