Thanks rdl6989.
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Posted on 05/20/2016 11:56:18 AM PDT by MtnClimber
The idea that our Universe is filled with dark matter has been around for nearly a century. When astronomers noticed that orbital speeds towards the edges of spiral galaxies remain the same or even increase slightly, rather than decrease, they surmised that either there must be some huge unseen mass driving the rotation, or that the laws of gravity given by Einstein's General Relativity need to be changed. They elected the first option.
Over that time, cosmologists have accumulated boatloads of evidence in favor of the notion that this invisible, "dark" matter -- which neither interacts with nor emits light -- comprises roughly 84% of the mass of the Universe. So compelling is this story that millions and millions of dollars have been spent on ingenious experiments to actually detect the stuff, but thus far, the particles have remained elusive.
It is partly because of dark matter's inherent ability to not be found that, in 1983, Israeli physicist Mordehai Milgrom proposed an upstart theory to challenge its dominance. Modified Newtonian dynamics, or MOND for short, dares to go where physicists of the past dared not: It slightly tweaks the laws of gravity put forth by Einstein's General Relativity. While the changes are subtle, only affecting Einstein's equations at very low accelerations, the ramifications are massive. General Relativity has remained essentially unscathed for over a century.
And yet MOND matches its audacity with surprising veracity. It successfully accounts for galaxy rotation curves just as well, and in some cases, even a little bit better than dark matter. Moreover, no evidence has come to light that conclusively disproves MOND. That's quite an accomplishment, as the annals of physics are littered with the corpses of theories that challenged General Relativity and failed.
(Excerpt) Read more at realclearscience.com ...
An interesting article.
ping
Great that they can soon test it.
You deniers are going to destroy the gravity credit market. The science is settled.
There is no such thing as “dark matter”. Galaxies are held together by electromagnetic forces, not gravity.
Of course we do. Trying to keep general relativity together has led to extreme absurdities like assuming the universe is over 19 parts in 20 composed of stuff we have no way to detect and doesn’t interact with anything (other than to magically and conveniently correct the errors in general relativity).
Plasma cosmology - a universe dominated by electromagnetism, rather than gravity - is providing answers that make sense where institutional science repeatedly fails.
Oh man. I was going to post “The science is settled.” but you beat me to it!
Well, you know, if the Navy gets a hold of it, they’ll rename it “Admiral Relativity”, and then we’ll really be in trouble.
Thanks rdl6989.
I thought General Relativity lost his command in some kind of scandal.
Maybe they should be asking themselves if something other than gravity is at work before conjuring up all these ad hoc just-so stories.
“Do We Need to Revise General Relativity?”
let’s not be general..
Do enlighten us.
Why do we assume that gravity and the speed of light are the same and constant throughout the universe? It is assumed that the mass of something can predicts its gravitational force (and vica-versa). What if gravity is proportional based on the location, temperature and/or speed of the mass? If dark matter has no mass, can it be matter at all?
I’ve always thought Newton was a fraud.
(kidding)
It depends on your point of view.
It’s all those Midiclorians that have gone over to the Dark Side.
Agreed. It’s all nonsense.
There is a series of books, “Hidden in Plain Sight” (used to be 99 cents each on Kindle), that suggests something along these lines too. I enjoyed the books, not too heavy, and thought provoking if you’ve spent time pondering physical “reality.”
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