双极化态柱面引力波的能量动量赝张量

利用Rosen-virbhadra（R—V）给出的引力场能量动量赝张量的一般表迭式,计算得到了双极化态柱面引力波能量动量的具体形式,并讨论了其正定性问题与渐进行为．发现：R—V的笛卡尔坐标形式是对双极化态的柱面引力波能量动量更为合理的表述．     

双极化态柱面引力波的能量动量赝张量

利用Papapetrou表述分别计算了柱坐标系和笛卡尔坐标系下双极化态柱面引力波的能量动量赝张量,发现笛卡尔坐标系是描述柱面引力波更为合理的坐标系,Papapetrou表述仍不能解决坐标的选择带来引力场能量动量不确定性的困难。     

基于Landau-Lifshitz表述的双极化态柱面引力波的能量问题

根据引力场能量动量的Landau-Lifshitz表述,求出了笛卡尔坐标系中的双极化态柱面引力波能量动量密度及角动量的具体形式;结果表明:采用笛卡尔坐标系可以合理地描述双极化态柱面引力波。     

基于Landau-Lifshitz表述的双极化态柱面

根据引力场能量动量的Landau-Lifshitz表述,求出了笛卡尔坐标系中的双极化态柱面引力波能量动量密度及角动量的具体形式;结果表明采用笛卡尔坐标系可以合理地描述双极化态柱面引力波.     

Quantum states of neutrons in the Earth's gravitational field.

The discrete quantum properties of matter are manifest in a variety of phenomena. Any particle that is trapped in a sufficiently deep and wide potential well is settled in quantum bound states. For example, the existence of quantum states of electrons in an electromagnetic field is responsible for the structure of atoms, and quantum states of nucleons in a strong nuclear field give rise to the structure of atomic nuclei. In an analogous way, the gravitational field should lead to the formation of quantum states. But the gravitational force is extremely weak compared to the electromagnetic and nuclear force, so the observation of quantum states of matter in a gravitational field is extremely challenging. Because of their charge neutrality and long lifetime, neutrons are promising candidates with which to observe such an effect. Here we report experimental evidence for gravitational quantum bound states of neutrons. The particles are allowed to fall towards a horizontal mirror which, together with the Earth's gravitational field, provides the necessary confining potential well. Under such conditions, the falling neutrons do not move continuously along the vertical direction, but rather jump from one height to another, as predicted by quantum theory.     

椭圆极化电磁波在界面的极化分析

运用波的极化概念,将入射的椭圆极化电磁波分解为互相正交的2个直线极化波,利用边界条件的匹配分别讨论它们与界面的作用结果,再进行合成;并就椭圆极化电磁波在界面垂直入射,以布儒斯特角入射及在界面发生全反射时的极化规律进行了分析.     

对-谐条件下纯引力纵波的不存在性

严格证明了在Ｖｉｅｒｂｅｉｎ表述的局域Ｌｏｒｅｎｔｚ群引力规范理论中,对于对角度规谐和条件（对谐条件）下的纯引力纵波,其对应的ＲｉｅｍｉｎｎＣｈｒｉｓｔｏｆｅｌ（ＲＣ）曲率张量的所有分量为零．即在该条件下不存在任何形式的纯引力纵波和纯曲率纵波．     

苯二胺对酒石酸-丙酮双有机底物化学振荡体系的扰动

研究了邻、间、对苯二胺对酒石酸-丙酮-Mn2+-KBrO3-H2SO4双有机底物化学振荡体系的扰动.结果表明,邻、间、对苯二胺的浓度分别在5.00×10-7~3.75×10-5,1.00×10-5~1.00×10-3和5.00×10-6~1.00×10-3mol.L-1范围内时,体系振幅的变化量与所加入邻、间、对苯二胺浓度的负对数呈良好的线性关系,相关系数分别为0.999 2,0.999 0和0.998 9,最低检测限分别为2.50×10-8,1.00×10-6和5.00×10-7mol.L-1.对可能的扰动机理进行了讨论.     

脉冲星发现50年

 脉冲星自1967年发现以来,50年的观测和理论研究取得巨大进展,期间曾2次获颁诺贝尔物理学奖。脉冲星以其高度致密和强引力场堪称宇宙天然实验室,可用来验证爱因斯坦广义相对论及进行引力波探测,推动了天文学与物理学研究的发展。本文简介了脉冲星的发现及其性质,并综述了脉冲星导航以及最近建成的500 m口径球面射电望远镜（FAST）的脉冲星探测研究进展。     

Detectable radio flares following gravitational waves from mergers of binary neutron stars

Mergers of neutron-star/neutron-star binaries are strong sources of gravitational waves. They can also launch subrelativistic and mildly relativistic outflows and are often assumed to be the sources of short γ-ray bursts. An electromagnetic signature that persisted for weeks to months after the event would strengthen any future claim of a detection of gravitational waves. Here we present results of calculations showing that the interaction of mildly relativistic outflows with the surrounding medium produces radio flares with peak emission at 1.4 gigahertz that persist at detectable (submillijansky) levels for weeks, out to a redshift of 0.1. Slower subrelativistic outflows produce flares detectable for years at 150 megahertz, as well as at 1.4 gigahertz, from slightly shorter distances. The radio transient RT 19870422 (ref. 11) has the properties predicted by our model, and its most probable origin is the merger of a compact neutron-star/neutron-star binary. The lack of radio detections usually associated with short γ-ray bursts does not constrain the radio transients that we discuss here (from mildly relativistic and subrelativistic outflows) because short γ-ray burst redshifts are typically >0.1 and the appropriate timescales (longer than weeks) have not been sampled.