Good question..........
My head hurts.
The argument can be (and is being) made that gravity does not pull. It pushes. Problem is, to push it depends on some sort of as-yet undetected “ether”. But it solves some of the paradoxes, like light slowing down in water and then speeding back up when it exits it.
My cat is heavy into string theory.
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Scientists: Dark matter exists
(SPACE.com)
New observations of a great big cosmic collision provide the best evidence yet that invisible and mysterious dark matter really does exist.
The collision, between two huge clusters of galaxies, is the "most energetic cosmic event, besides the Big Bang, that we know about," said Maxim Markevitch of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.
The impact split normal matter and dark matter apart, rendering the dark matter's gravitational presence observable.
Scientists announced the discovery today in a teleconference with reporters.
The normal matter in the cosmos -- atoms that make up stars, planets, air and life -- accounts for only a small fraction of what must exist, based on the fact that without an additional source of gravity, galaxies would fly apart and galaxy clusters could not hold together as they do.
Nobody knows where all that gravity comes from, so scientists say there must be some invisible stuff out there, which they call dark matter. Its presence is indirectly supported by many observations. Given what's known, this is the makeup of the universe:
5 percent normal matter
25 percent dark matter
70 percent dark energy
Dark energy is an even more mysterious phenomenon, a force of some sort that beats out gravity and is causing the universe to expand at an ever-faster pace.
Some theorists have suggested that rather than invoking dark matter, perhaps existing ideas about gravity might be wrong. Maybe gravity is stronger on intergalactic scales than what is predicted by Newton and Einstein.
And all astronomers agree that dark matter is such an exotic idea as to border on the crazy. "A universe that's dominated by dark stuff seems preposterous, so we wanted to test whether there were any basic flaws in our thinking," said Doug Clowe of the University of Arizona at Tucson, and leader of the study. "These results are direct proof that dark matter exists."
Splitting matter
Clowe and colleagues used NASA's Chandra X-ray Observatory to study the galaxy cluster 1E0657-556, which contains a bullet-shaped cloud of superheated gas. X-rays show the shape was produced by cosmic winds created in a high-speed collision of two clusters of galaxies.
Other telescopes were used to locate and quantify the mass in the clusters. They actually measured the effect of gravitational lensing, in which gravity from the clusters distorts light from thousands of background galaxies, as predicted by Einstein's theory of general relativity.
The dark matter is not seen, but its gravity has a predictable effect on the observations. The resulting blue color in a new image represents the gravity fields observed by noting how the light from each background galaxy is distorted. Here's what the image reveals:
The hot gas -- normal matter -- was slowed by a drag force described as the cosmic equivalent of air resistance. But the dark matter was not slowed by this effect, presumably because it does not interact with normal matter, as theory had predicted.
So the normal matter and dark matter became separated.
"This proves in a simple and direct way that dark matter exists." Markevitch said in the teleconference.
Other theories must cope
The finding provides further evidence that standard Newtonian gravity, which keeps planets in orbit around the sun, is the glue that makes things stick on the largest scales, too.
It is still possible there is some modification of gravity going on, but these findings make it less necessary to have such theories, said Sean Carroll, a cosmologist at the University of Chicago who was not involved with the study. "No matter what you do [in devising new theories] you're going to have to believe in dark matter."
"We've closed this loophole about gravity, and we've come closer than ever to seeing this invisible matter," Clowe said. "This is the first time we've had a direct detection of dark matter" in which you can't explain the results with any altered-gravity theory, he said.
The findings will be detailed in an upcoming issue of the Astrophysical Journal Letters.
God, who at various times and in various ways spoke in time past to the fathers by the prophets, has in these last days spoken to us by His Son, whom He has appointed heir of all things, through whom also He made the worlds; who being the brightness of His glory and the express image of His person, and upholding all things by the word of His power, when He had by Himself purged our sins, sat down at the right hand of the Majesty on high, having become so much better than the angels, as He has by inheritance obtained a more excellent name than they. Hebrews 1:1-4 (NKJV)
In other words:
There are more things in heaven and earth, Horatio,
Than are dreamt of in your philosophy.
Most of this is over my head, except the string theory. My theory is if you see a loose string on your cargo shorts .... don’t pull it because if you do your pants might fall off.
me not understand
Well, since the world ain't flat, there's probably a whole lot more to be discovered.
At a time when “queer” still meant strange, JBS Haldane In the 1920’s observed,
“I have no doubt that in reality the future will be vastly more surprising than anything I can imagine. Now my own suspicion is that the Universe is not only queerer than we suppose, but queerer than we can suppose.”
Nice. I wish I understood what he was trying to say better. How it be tested? Better yet, how can it be exploited?
Ping for later...
Worth repeating.
If it is simple, and there are no demonstrable counterexamples, then we may presume it is correct.
That’s deep, man
I firmly believe that when my soul is released from this earth that God will make all things known. While I may have the potential for massive amounts of knowledge, my psyche cannot handle it. I would go crazy if God allowed me to know everthing that is knowable in the universe. Some insanity is just a glimpse to what can be known after I pass on. Sometimes you just have to step back from the edge.