Editing Scale invariance (section)

===Cosmology===<!-- This section is linked from [[Cosmic inflation]] -->
In [[physical cosmology]], the power spectrum of the spatial distribution of the [[cosmic microwave background]] is near to being a scale-invariant function. Although in mathematics this means that the spectrum is a power-law, in cosmology the term "scale-invariant" indicates that the amplitude, {{math|''P''(''k'')}}, of [[primordial fluctuations]] as a function of [[wave number]], {{mvar|k}}, is approximately constant, i.e. a flat spectrum. This pattern is consistent with the proposal of [[cosmic inflation]].