Ask Ethan #67: Dark Matter vs. Dark Energy (Synopsis)

“We are incredibly heedless in the formation of our beliefs, but find ourselves filled with an illicit passion for them when anyone proposed to rob us of their companionship.” -James Harvey Robinson

The Universe seems to be full of contradictions. On one hand, everywhere we look -- in all directions and at all locations -- we find that it's full of stars, galaxies and clusters. There are regions pretty much everywhere where, in the great cosmic struggle between all the pulls and pushes, gravitation has won.

Image credit: NASA; ESA; G. Illingworth, UCO/Lick Observatory and the University of California, Santa Cruz; R. Bouwens, UCO/Lick Observatory and Leiden University; and the HUDF09 Team. Image credit: NASA; ESA; G. Illingworth, UCO/Lick Observatory and the University of California, Santa Cruz; R. Bouwens, UCO/Lick Observatory and Leiden University; and the HUDF09 Team.

So why is it, if gravitation can win pretty much everywhere, did the Universe not recollapse? How did acceleration and dark energy come to dominate the Universe? And how are all of these things consistent with what we know about dark matter, dark energy and the Universe as a whole?

Image credit: Don Dixon, from Scientific American 15, 66–73 (2006)  doi:10.1038/scientificamerican0206–66sp. Image credit: Don Dixon, from Scientific American 15, 66–73 (2006) 
doi:10.1038/scientificamerican0206–66sp.

Get the answers as Tom Anderson becomes our fourth giveaway winner on this latest edition of Ask Ethan!

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Presumably any ordinary matter still in the underdense regions will never form stars or galaxies. Do you have an estimate of what fraction of the ordinary matter participates in galaxies, and intergalactic gas within galaxy clusters. If you postulate a purpose for the universe is to make galaxies, then this fraction would be considered to be the (matter) efficiency of the universe. Is it much less than 1?

By Omega Centauri (not verified) on 19 Dec 2014 #permalink

Our Universe is a larger version of a galactic polar jet.

'Was the universe born spinning?'
http://physicsworld.com/cws/article/news/46688

"The universe was born spinning and continues to do so around a preferred axis"

Our Universe spins around a preferred axis because it is a larger version of a galactic polar jet.

'Mysterious Cosmic 'Dark Flow' Tracked Deeper into Universe'
http://www.nasa.gov/centers/goddard/news/releases/2010/10-023.html

"The clusters appear to be moving along a line extending from our solar system toward Centaurus/Hydra, but the direction of this motion is less certain. Evidence indicates that the clusters are headed outward along this path, away from Earth, but the team cannot yet rule out the opposite flow. "We detect motion along this axis, but right now our data cannot state as strongly as we'd like whether the clusters are coming or going," Kashlinsky said."

The clusters are headed along this path because our Universe is a larger version of a polar jet.

It's not the Big Bang; it's the Big Ongoing.

Dark energy is dark matter continuously emitted into the Universal jet.

Our Universe is a larger version of a galactic polar jet.

No it isn't. We're not moving in anything like the appropriate manner.

Ignorant humans are "full of contradictions," but when that ignorance is lifted over time, the Universe always shows that it is certainly NOT "full of contradictions": http://sensibleuniverse.com/slides — Time for everyone to make an effort to do some real scientific thinking and *rethinking*.

By Alex Mayer (not verified) on 21 Dec 2014 #permalink

It seems obvious that gravity in black holes increases super-exponentially due to large amounts of matter falling toward the center at the speed of light - hence the super gravity effect on galaxy formation mistaken for "dark matter."

As for "dark energy," it is equally obvious that the synergistic interaction ofl black hole super gravity wells is causing our holographic reality to shrink. The universe is not expanding... we are getting smaller.

This stretching of the space-time continum results in the decay product we call "time.

By Mike of Earth (not verified) on 20 Jun 2015 #permalink