Home » 学术转发 » 名词 » 哈勃–勒梅特定律 Hubble's law

哈勃–勒梅特定律 Hubble's law

Hubble's law, also known as the Hubble–Lemaître law or Lemaître's law, is the observation in physical cosmology that galaxies are moving away from Earth at speeds proportional to their distance. In other words, the farther they are, the faster they are moving away from Earth. The velocity of the galaxies has been determined by their redshift, a shift of the light they emit toward the red end of the visible spectrum.

Hubble's law is considered the first observational basis for the expansion of the universe, and today it serves as one of the pieces of evidence most often cited in support of the Big Bang model. The motion of astronomical objects due solely to this expansion is known as the Hubble flow. It is described by the equation v = H0D, with H0 the constant of proportionality—the Hubble constant—between the "proper distance" D to a galaxy, which can change over time, unlike the comoving distance, and its speed of separation v, i.e. the derivative of proper distance with respect to cosmological time coordinate. (See "Uses of the proper distance" for some discussion of the subtleties of this definition of "velocity".)

参考资料:

https://en.wikipedia.org/wiki/Hubble%27s_law

https://zh.wikipedia.org/wiki/哈勃–勒梅特定律

6 次浏览
FavoriteLoading加入收藏


Leave a comment

作者归档

文章分类

最近发布(原创文章+学术转发)

最近发布(其他转发+默认分类)