Cosmic Spin
Article Published: 14 June 2021
Possible observational evidence for cosmic filament spin
Peng Wang, Noam I. Libeskind, […]Quan Guo
Nature Astronomy (2021)
How angular momentum is generated in a cosmological context is one of the key unsolved problems of cosmology. In the standard model of structure formation, small overdensities present in the early Universe grow via gravitational instability as matter flows from under- to overdense regions. Such a potential flow is irrotational or curl free: there is no primordial rotation in the early Universe and angular momentum must be generated as structures form.
New Scientist citing the above article.
Enormous strands of galaxies in the cosmic web appear to be spinning
SPACE 14 June 2021
By Leah Crane
Some of the largest structures in the universe appear to be rotating. The filaments of galaxies forming the cosmic web that stretches between galaxy clusters seem to be spinning, which could help us figure out why galaxies themselves – and everything else in space – rotate.
How rotation is generated in space is a long-standing problem in astrophysics. “Not only are the galaxies spinning, but also the stars within the galaxies, and the Earth is spinning, and the Earth around the sun and the moon around the Earth. Pretty much the whole universe is spinning,” says Noam Libeskind at the Leibniz Institute for Astrophysics Potsdam in Germany. “We don’t really know why, and one way to try to answer that is to figure out where the spinning stops.”
Cosmic Spin and the Megaverse
The Megaverse idea makes two predictions often quoted in my blogs and vixra articles.
Ho will increase over time due to the increasing strength of cosmic gravity as our universe expands into space.
There will be a dipole in the sky. The expansion rate will not be isotropic. The local cosmos will not be homogeneous just as our local universe is not.
But there is a third prediction hidden somewhere in my Google docs, if not in the blogs.
Our universe will have angular momentum. The cosmic black hole which gave birth to the universe will have had spin.
All black holes have spin, it's just a matter of how much. Certainly, those formed from binary mergers have significant spin.
Now measuring this angular momentum wasn't going to be easy. With a universe which is more than 92 billion light years across, the angular momentum is spread out thinly. The skater slows down as the arms spread out.
But here today we had reports of unexplained spin in the universe. It's far from conclusive. The spin is not universal. Spins in different parts may cancel out. But it's a start.
Ho was a constant a few years ago. The dipole in the sky is still in doubt. Time and better data as always.
Apparently there is no angular momentum in the early universe. We'll see.