编者的话

“标量”一词在基础物理中和理论物理中通常有不同的含义 .在基础物理中 ,一般理解标量是可用 1个实数描写的物理量 .因此 ,质量、温度、劲度系数等都是标量 ,这一点本文已经说清楚了 .在理论物理中 ,标量、矢量和张量都是按这个量在坐标转动下的变换性质来定义的 .例如位置矢量r ,在坐标系A中的分量是x ,y,z ,即x1,x2 ,x3 .在坐标系A′中的分量是x′1,x′2 ,x′3 ,二者的关系是x′i= jaijxj (1 )式中aij(共 9个 )是描写坐标转动 ,即A与A′的关系的量 ,满足detaij=1所以 ,在理论物理中 ,矢量的定义是 :矢量是用 3个实数x ,y,z描写的、在坐…     

证明K·x-ωt是一个四维标量

本文从狭义相对论的角度，在四维时空中定义波动、波长、周期等波动学中的基本概念；并由这些概念出发、用洛仑兹换得到Ｋ·ｘ－ωｔ是一个四维标量。     

物理量和数学量的联系与区别

在中学阶段，物理量有标量和矢量2种类型，数学量有算术量、代数量和向量3种类型．它们之间既相互联系，又相互区别．弄清它们之间的关系与区别，对于深刻理解各种类型物理量的运算大有益处。     

Banach空间中的单调迭代法及其应用

本文讨论了Banach空间中的单调迭代法，并将结果应用到实数空间R^1的简单迭代法中。     

代数量的教学探讨与思考

我们知道物理量有标量和矢量．在量与量的计算中，纯标量间的运算没有多少物理意义，而矢量间的运算，无论是加减、乘除或微积分，在运算时都必须考虑方向，这样给矢量之间和各种运算带来诸多不便，请看下面三个问题。     

物理力学中的两种量度和两种方法

牛顿定律、动量定理和功能关系的问题,实际上是力学中的矢量方法和标量方法,或说是矢量力学和标量力学的问题。两种力学所涉及到的典型物理量则是动量和动能,本文对这两种方法作一些分析讨论:     

要掌握物理量定义的方法

建立物理量的目的是通过该量来表征物质或物体的状态或性质，并通过探求各量之间所表征的全部内容，集中地包含在它的定义式中．因此，掌握物理量定义的方法，对物理教学具有重要意义．     

关于“质点角动量”学习中的几个问题

角动量是描述物体运动状态的重要物理量，初学者常会感到困难．本文就如何理解学习质点角动量知识，谈几点意见． 什么是角动量．在描述质点平动运动时，“线动量”是很有用的物理量．那么，在转动运动中与线动量相类似的物理量就是角动量．若质量为ｍ、线动量为ｍｖ的质点，相对于惯性系原点的位矢为ｖ，我们定义这质点对原点Ｏ的角动量为：Ｌ＝ｖ×ｍｖ． 角动量是矢量．从定义式中可看出，角动量是涉及矢积的一个物理量，其方向由矢积右手法则给定，即方向垂直于位失和动量决定的平面，如图１（ａ）、（ｂ）中角动量入方向的标示． 角动…     

标量湍流的能量传输特性

应用直接数值模拟数据,从标量湍流传输的三波关系出发,进行湍流及标量湍流传输谱的多尺度分析,研究不同尺度间的能量传输性质,证实标量能量的传输与湍动能传输具有不同性质,大尺度速度脉动对标量传输有较大贡献,尤其是与标量小尺度脉动的相互作用,使标量模拟需要有比速度场更高的网格分辨率;并发现标量湍流的能量传输具有明显的非局部性;另外,定义了能量传输系数,发现在相同的Re数和Pe数条件下,标量湍流的对流惯性较速度脉动的惯性子区宽.     

浅析线性变量的平均值及其应用

1线性变量平均值的定义 当物理量y随着物理量x变化时，若x的变化范围为x1～x2，则在这段范围内，y相对于x的平均值是     

Slowly rotating universes with radiating perfect fluid distribution coupled with a scalar field in general relativity

Along with the presentation of some interesting new analytic solutions, the dynamics of slowly rotating radiating perfect fluid universes coupled with a scalar field are investigated, and their physical and geometrical properties are studied from various angles. The rotational perturbations of such models are examined in detail in order to substantiate the possibility that the universe is endowed with some rotation. The nature and role of the metric rotation which is related to the local dragging of inertial frames and that of the matter rotation are studied. The effects of the radiation and the scalar fields on the rotation are discussed. The periods of physical validity for some of the models and the restrictions on the radii of the models for real astrophysical situations are found. Most of the rotating models obtained here turn out to be expanding ones as well, and may be taken as good examples of real astrophysical objects in this universe.     

Infinite symmetry algebras of extended supergravity theories

When extended supergravity theories with noncompact symmetry groups are written in a physical gauge, the noncompact symmetries join with the supersymmetries to generate an infinite-dimensional algebra. The details are worked out explicitly for a two-dimensional theory with an SU(1, 1) internal symmetry. Our analysis confirms the observation of Ellis et al. that the infinite rigid superalgebra should be obtained from the finite-dimensional local superalgebra by replacing scalar fields with their asymptotic values at infinity. The infinite algebra is described by extending the super-Poincaré generators to functions on the coset space defined by the scalar fields at infinity. While mathematically nontrivial, this result is, in a certain sense, trivial from a physical point of view.     

Induced gravity and cosmology

We propose a fully conformal invariant theory describing gravity as a spontaneously broken theory. Newton's constant is automatically generated. We find through the study of classical solutions of the equations of motion that the breakdown of conformal symmetry can take place at the tree approximation without introducing arbitrary forms for the scalar potential. Using cosmological metrics, which we find natural from the physical point of view, some conclusions can be drawn regarding the nature of those metrics. The case of constant scalar curvature is particularly interesting, and gives rise to a gravitational version of the Goldstone theorem.     

Stability problem in Rindler spacetime

The stability problem of the Rindler spacetime is carefully studies by using the scalar wave perturbation. Using two different coordinate systems, the scalar wave equation is investigated. The results are different in the two cases. They are analysed and compared with each other in detail. The following conclusions are obtained: (a) the Rindler spacetime as a whole is not stable; (b) the Rindler spacetime can exist stably only as part of the Minkowski spacetime, and the Minkowski spacetime can be a real entity independently; (c) there are some defects for the scalar wave equation written by the Rindler coordinates, and it is unsuitable for the investigation of the stability properties of the Rindler spacetime. All these results may shed some light on the stability properties of the Schwarzschild black hole. It is natural and reasonable for one to infer that: (a) perhaps the Regge--Wheeler equation is not sufficient to determine the stable properties; (b) the Schwarzschild black hole as a whole might be really unstable; (c) the Kruskal spacetime is stable and can exist as a real physical entity; whereas the Schwarzschild black hole can occur only as part of the Kruskal spacetime.     

Canonical quantization of two-dimensional gravity

A canonical quantization of two-dimensional gravity minimally coupled to real scalar and spinor Majorana fields is presented. The physical state space of the theory is completely described and calculations are also made of the average values of the metric tensor relative to states close to the ground state.     

Hawking–Unruh effect and the entanglement of two-mode squeezed states in Riemannian space–time

We consider the system of free scalar field, which is assumed to be a two-mode squeezed state from an inertial point of view. This setting allows the use of entanglement measure for continuous variables, which can be applied to discuss free and bound entanglement from the point of view from non-inertial observer.     

SURFACE ENERGIES OF ATOMIC NUCLEI AND THE MASS OF THE SCALAR MESON

Assuming that the nuclear binding is dominated by a real scalar meson field,the mass of this meson is calculated to be 472 MeV from the nuclear surface tension coeffici-ent,by Thomas-Fermi method and Van der Waals approximation.The agreement between this value and the mass of a chief scalar meson in the OBEP theory of nuclear force indicates that a more serious investigation of above assumption should be valuable.     

Quaternion physical quantities

Quaternions consist of a scalar plus a vector and result from multiplication or division of vectors by vectors. Division of vectors is equivalent to multiplication divided by a scalar. Quaternions as used here consist of the scalar product with positive sign plus the vector product with sign determined by the right-hand rule. Units are specified by the multiplication process. Trigonometric functions are quaternions with units that can satisfy Hamilton's requirements. The square of a trigonometric quaternion is a real number provided that the product of the scalar number and the vector is not commutative. Maxwell's electromagnetic equations for empty space can be represented by a single quaternion equation.