哈勃法则[Hubble Law] - 达人(其实～我是卧底，来自外星)

2004/11/11 | 哈勃法则[Hubble Law]
类别(Ω〖物理〗) | 评论(0) | 阅读(46) | 发表于 13:45: Using measurements of redshifts, Hubble proposed in 1929 that almost all galaxies were moving away from the Milky Way. He postulated that recessional velocity was directly proportional to distance r,
(1)

where H is a constant known as the Hubble constant. It is given by
(2)

where a is the expansion parameter. In the Friedmann-Lemaître cosmological model,
(3)

Hubble's Law is an immediate consequence of assuming homogeneity and isotropy of the universe.However, the "roughly linear relation" claimed by Hubble shows the galactic recessional velocities to be almost uncorrelated with distance! By 1931, better data showed a linear slope was actually present and allowed its slope to be estimated (Weinberg 1988, p. 26).; 0