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Algenon the mouse
2004-Feb-22, 12:06 AM
http://www.hindustantimes.com/news/181_580...95,00040005.htm (http://www.hindustantimes.com/news/181_580795,00040005.htm)


Hubble measurements support Einstein prediction
Associated Press
Los Angeles, February 21

The mysterious "dark energy" that is pushing apart the universe appears to be the constant force that Albert Einstein once predicted, according to measurements made by the Hubble Space Telescope.

NASA scientists announced their findings on Friday, and details are to appear in an upcoming issue of Astrophysical Journal.

The force is an unknown form of energy that behaves in an opposite manner from the pull of gravity. Dark energy causes the galaxies within the universe to move apart from one another at ever-increasing speeds.

Einstein called the force the "cosmological constant." He theorised its existence to balance the universe against normal gravity and keep it from collapsing on itself.

Einstein ultimately dismissed the theory as his greatest blunder, but subsequent observations of supernovas, or distant stars that exploded long ago, gave it credence. Scientists now know dark energy causes the universe to expand and accelerate. It makes up an estimated 70 per cent of the universe.

What was unclear is whether dark energy is stable.

If it grows stronger with time, the universe could end with galaxies, stars, planets and, ultimately, atoms coming unglued in a violent expansion that theorists call the "big rip."

In the alternative, dark energy could fade away to the point where it flipped in force, pulling the universe back together in what's called the "big crunch.

Tiny
2004-Feb-22, 09:49 PM
I was wonder where did the Dark energy itself come from? From Matter to energy (E=mc^2)? Or forces covert to energy. :ph34r:

Victoria
2004-Feb-23, 02:31 AM
Best lesson learned...nothing personal. Einstein relates fact to nature.

Faulkner
2004-Feb-23, 10:00 AM
The force is an unknown form of energy that behaves in an opposite manner from the pull of gravity. Dark energy causes the galaxies within the universe to move apart from one another at ever-increasing speeds.


Ha ha... Show me a scientist that admits there's a FIFTH force!!!
Conservative *******s, the lot of 'em!!!

IT'S OBVIOUS...that there is an OUTSIDE pull!!!

ADMIT OR QUIT!!! :rolleyes:

Victoria
2004-Feb-24, 01:34 AM
Show me a scientist whom admits there is a fifth force. heh-heh :P 5th diminsion. Right, I have trouble spelling it. :D Really now, a fifth dimension you say, I wonder the possibilities.[QUOTE]

Weaselbunny
2004-Feb-24, 01:17 PM
Why won't they admit it when it's so obvious Faulkner? Would it conflict with other theories?

Why are these people so conservative? They have minds capable of such amazing feats and yet they'll close their minds, cover their ears and sing la la la! :angry:

Victoria
2004-Mar-01, 02:18 AM
Experience is a lifestyle. Either you accept the challenge or dwindle. :D :P

Tom2Mars
2004-Mar-01, 05:54 AM
What would happen to the equations if you replaced infinity with 0. Everything from nothing. How else could all this(the universe) have fit into such a small, initial infintessimal point?

GOURDHEAD
2004-Mar-01, 01:44 PM
At the risk of further muddying up the epicycling, let me offer a wild speculation concerning the expansion force. At the close of the inflation epoch assumed by its advocates to have been at 10^-35 (superscript negative 35) seconds after time zero of the big bang, the universe is believed, again by big bang advocates, to have been no larger than the volume of a sphere of one light year radius and to consist of a very dense collection of photons and plasma. Ninety-five to ninety-seven per cent of this energetic soup is energy at the very high gamma energy level due to matter anti-matter particle annihilations to generate the current matter configuration of the universe. The expansion rate outward from this primordial one light year radius after 10^-35 seconds is much slower than light speed (probably ?) allowing this gamma level photon energy to supply an outward pressure on spacetime in opposition to the very intense (orders of magnitude larger than current) gravitational field. Also, due to the plasma state of the matter existing until the transparency state was achieved (release of what is now observed as the cosmic background radiation) and the likely equidistribution of kinetic energy across the electrons and protons, the electrons would have outraced the protons generating an inner sphere of mutually repelling protons surrounded by a spherical shell of mutually repelling electrons. (I'm not sure whether the lifespan of any neutrons that come and go during this phase allows them to be worthy of consideration, nor, if so, how to consider them.) Also the photons have outraced the electrons (most escaping prior to the forming of the proton sphere and the electron shell and their respective opacities).

It seems reasonable to assume that most of the high energy matter-antimatter gammas (MAGs) have very quickly reached the space-time horizon since they travel faster than the post inflation rate of space-time expansion and faster than the electron shell. By this time they will be "pairforming" and annihilating at whatever rates the laws of physics allow (beyond my ability to speculate quantitatively) while bouncing back and forth between the horizon and the electron shell all within an unimaginably intense electric and magnetic field environment generated by the churning electron shell and the proton sphere.

How could space-time avoid being stretched? And then momentum takes over. :unsure: :unsure: