GEOMETRICAL OPTICS IN AN INHOMOGENEOUS UNIVERSE  

作　　者：FANG Lizhi WU Xiangping 方励之;武向平(Beijing Astronomical Observatory,Academia Sinica,Beijing)

机构地区：[1]Beijing Astronomical Observatory,Academia Sinica,Beijing

出　　处：《Chinese Physics Letters》1989年第5期233-236,共4页中国物理快报（英文版）

摘　　要：In comparison with a homogeneous universe,a clumpy universe possess two types of effects on geometrical optics:1.the convergence due to the gravititational-lens effects of the clumps;t.the divergence due to the less mass density outside the clumps.On the other hand,thermodynamics requires that the total effects are double offset.This give us an effective method to judge the rationality of various calculations of the lensing effect in a clumpy universe.

关 键 词：UNIVERSE DIVERGENCE THERMODYNAMICS 

分 类 号：P15[天文地球—天文学]