Horizon problem

Full-sky image derived from nine years' WMAP data

When we look at the CMB it comes from 46 billion comoving light years away. However, when the light was emitted the universe was much younger (300,000 years old). In that time light would have only reached as far as the smaller circles. The two points indicated on the diagram would not have been able to contact each other because their spheres of causality do not overlap.

The horizon problem (sometimes called the homogeneity problem) is a problem with the standard cosmological model of the Big Bang which was identified in the late 1960s, primarily by Charles Misner. It points out that different regions of the universe have not "contacted" each other because of the great distances between them, but nevertheless they have the same temperature and other physical properties. This should not be possible, given that the transfer of information (or energy, heat, etc.) can occur, at most, at the speed of light.

单词	Horizon problem
释义	Horizon problem 英语百科 Horizon problem The horizon problem (sometimes called the homogeneity problem) is a problem with the standard cosmological model of the Big Bang which was identified in the late 1960s, primarily by Charles Misner. It points out that different regions of the universe have not "contacted" each other because of the great distances between them, but nevertheless they have the same temperature and other physical properties. This should not be possible, given that the transfer of information (or energy, heat, etc.) can occur, at most, at the speed of light.
随便看	chemosensillum的意思 Chemosensing的意思 chemosensing system的意思 chemosensitisation的意思 chemosensitive的意思 chemosensitive cell的意思 chemosensitiver的意思 chemosensitivities的意思 chemosensitivity的意思 chemosensitization的意思 Chemosensitizer的意思 chemosensitizers的意思 Chemosensitizing的意思 Chemosensor的意思 chemosensors的意思 chemosensory的意思 chemosensory hair的意思 chemosensory neuron的意思 chemosensory organ的意思 chemosensory seta的意思 chemosensory transducer的意思 Chemosept的意思 chemoserotherapy的意思 chemoserotherapy analyzer的意思 chemoses的意思