- Jan 12, 2005
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Modern cosmologists ressurected Einstein's "cosmological constant" (which he postulated as a fix to general relativity) in order to deal with the so-called "dark energy", believed to be the cause of the observed accelerative expansion of the universe. The "Big Rip" theory is based on the assumption that the "power" of dark energy is significantly larger than in the mainstream model.
The Big Rip
An excerpt:
The Big Rip
An excerpt:
Driving the known acceleration of the universe's expansion is a mysterious thing is called dark energy, thought of by scientists as anti-gravity working over large distances.
Conventional wisdom holds that the acceleration will proceed at a constant rate, akin to a car that moves 10 mph faster with each mile traveled. With nothing to cap the acceleration, all galaxies will eventually recede from one another at the speed of light, leaving each galaxy alone in a cold, dark universe within 100 billion years. We would not be able to see any galaxies outside our Milky Way, even with the most powerful telescopes.
That's the conventional view, remarkable as it sounds.
The Big Rip theory has dark energy's prowess increasing with time, until it's an out-of-control phantom energy. Think of our car accelerating an additional 10 mph every half mile, then every hundred yards, then every foot.
Before long, the bumpers are bound to fly off. Sooner or later, our hypothetical engine will come apart, regardless of how much we spend on motor oil.
Countdown to demise
The projected end is, reassuringly, 20 billion years away. If our species survives the next 19 billion years (and there are serious doubts about this, given our Sun's projected fate) here are some signs that scientists of the future will want to look for.
A billion years before the end, all galaxies will have receded so far and so fast from our own as to be erased from the sky, as in no longer visible.
When the Milky Way begins to fly apart, there are 60 million years left.
Planets in our solar system will start to wing away from the Sun three months before the end of time.
When Earth explodes, the end is momentarily near.
At this point, there is still a short interval before atoms and even their nuclei break apart. "There's about 30 minutes left," Caldwell said, "But it's not quality time."
And then what? Does the universe recycle itself? Is there something after nothing?
"We're not sure what happens after that," Caldwell says. "On the face of it, it would look like time ends."