Thursday, August 4, 2016
Latest Deep Sky Image Confirms Accelerating Cosmos and Vacuum Energy's Role
New Sloan Deep Sky Survey III image with over 4 quadrillion stars.
As I pointed out in previous posts, the Sloan Deep Sky Survey is an important component of cosmological data providing us with not only a refined cosmic perspective but also accurate measures of the cosmos pertaining to its rate of expansion. That dark energy was likely accelerating the expansion was known as long ago as 2000, from measurements made by the Maxima and Boomerang craft. The combined data enabled a power spectrum of spatial temperature fluctuations to be assembled (see graphic) using a spherical harmonic function fit. The multi-humped graph plotted mean square temperature. fluctuation (in micro-Kelvin on vertical axis) vs. multipole order ℓ on the abscissa. This multipole order also coincides with the spherical harmonic order index ℓ. The temperature differences dTi appeared at angular separations of π/ ℓ and displayed a non-uniformity on angular scales of about 1.0 deg. The first peak occurred at ℓ= 200 and the 2nd peak was asymmetrically spaced relative to it.