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Number of Results: 1 Search : cosmic microwave background anisotropy

cosmic microwave background anisotropy nâhamsângardi-ye tâbeš-e rizmowj-e paszaminé-ye keyhâni Fr.: anisotropies du rayonnement du fond cosmique microonde Tiny fluctuations in the intensity of the
→ T/T
and expand them on the sky in → _{0}spherical harmonic
series
ΔT/T (θ,φ) = Σ
_{0}a(θ,φ), where
θ and φ are the → _{lm}Y_{lm}spherical polar coordinates,
Y is the spherical harmonic functions with
→ _{lm}multipole index l, and
the sum runs over l = 1, 2, ..., ∞, m = -l, ..., l, giving 2l + 1
values of m for each l, and a is the
multipole moment of the decomposition.
The power spectrum of the anisotropies is defined as
_{lm}C≡ mean | _{l}a |_{lm}^{2} = 1/(2l + 1)
Σ mean | a |_{lm}^{2}.
See also → CMB angular power spectrum.→ |