The immensity of the universe; new measurement (The nature of a \'Creator\')

by David Turell @, Saturday, March 18, 2017, 14:31 (2567 days ago) @ David Turell

dhw:
*** Universe is Not Expanding After All, Controversial Study ...
www.sci-news.com/astronomy/science-universe-not-expanding-01940.html


David: Interesting outlier study, with the redshift reasoning unexplained, and the vastness of the universe also unexplained by their theory. Brightness has always been a problem in figuring out astronomical distances. We are beyond 'standard candle' studies such as this inept one uses. They object to supernova studies which make expansion much clearer?

Here is a new measurement for cosmic distances as the universe expands:

https://www.newscientist.com/article/2124950-cosmological-ruler-could-help-us-get-the-m...

"Currently, astronomers measure distances by taking advantage of the fact that the distribution of galaxies throughout the universe fluctuates in predictable ways, a relic of sound waves that echoed through the early universe.

"In its infancy, the universe was a hot soup of matter that was distributed in a mostly uniform fashion, with a few dense spots of dark matter. About 30,000 years after the big bang, gravity made normal matter collapse around those dense spots, but pressure from photons caused it to rebound outward again. This cosmic bounce created acoustic waves, called baryon acoustic oscillations (BAO), that expanded outwards in a spherical shape and carried normal matter with them.

"These waves kept expanding until the cooling of the universe halted their progress, freezing each of them at roughly the same point in their expansion. The resulting dense patches of matter at the edge of the waves and their points of origin were more likely to form galaxies, creating a lasting imprint of the acoustic waves that rang out in the early universe.

“'All our galaxies are close to the surface of these spherical shells or their centre,” says Glenn Starkman at Case Western Reserve University in Ohio.
Because each of these spherical shells is the same size, astrophysicists use the distance between a central galaxy cluster and galaxy clusters at the edge of the wave – about 500 million light years – as a kind of cosmological ruler.

"But it isn’t perfect: as the universe aged, this neat structuring of galaxies blurred as gravity and magnetic fields pulled galaxies in different directions. That means that to use the technique mathematical models are needed to make a series of assumptions about how galaxies have shifted over time. Some BAO distances could be spot on, but others are off by several per cent, and there is no way to tell which ones are which.

"Now, Starkman and his colleagues have come up with a ruler that sidesteps the need for these assumptions. Instead of following the galaxies’ motions, the team measure distance relative to an unmoving mathematical midpoint in the BAOs called the linear point. Starkman says the technique is up to four times more accurate than existing methods.

"Being able to measure very large cosmological distances is critical to understanding the nature of dark energy, says Will Percival at the University of Portsmouth in the UK. But while using the linear point appears to reduce the number of errors in estimating cosmological distances, he says, it’s not yet clear whether using it will yield more precise measurements than existing methods.

"For more precise measurements, we will have to wait for the results of future galaxy surveys such as the European Space Agency’s Euclid mission, which will observe areas of the universe that aren’t polluted by light from the Milky Way. The data from these surveys will be at least 10 times more precise than existing surveys, Percival says, and will provide a good opportunity to test whether the proposed cosmological ruler is better than current measurements."

Comment: For most universe expansion is undoubted, and measurements are improving. At least we are beyond Cepheid stars as the only measure of distance.


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