T
twilyth
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It's a long article but interesting. Excerpt is from the end on page 3
The universe would live on forever, though only as a shadow of its former vibrant self. It would gradually become darker, colder, and emptier as the scant remaining matter decays or gets sucked up by the giant black holes at the core of every galaxy. Once they have gobbled up every semblance of matter, in about 10[^]100 years, even the black holes will evaporate and disappear.
That is a bleak scenario, but it’s not the bleakest, says Dartmouth College physicist Robert Caldwell. According to his calculations, the Big Chill would be a happy ending compared with something he and his colleague Marc Kamionkowski have dubbed the Big Rip. In his 2003 paper “Phantom Energy and Cosmic Doomsday,” Caldwell explored the possibility that in the future dark energy will grow even stronger. At present it makes itself felt only over huge distances, such as the gaps between clusters of galaxies, but Caldwell says that some theories indicate that dark energy might just be kicking into gear. If that is the case, then within 20 billion years—fairly early in our sojourn around a red dwarf—dark energy could start to wreak havoc on much smaller objects.
Stars would be yanked away from galaxies. Then planets would be pulled from their stars. And in one extraordinary half hour, dark energy would progressively tear even the smallest pieces of the universe apart. Layer by layer, humanity’s home planet would be dismantled—first the atmosphere, then the crust, all the way down to the core—in a fantastic explosion. “Anything resting on the planet will just—whoosh—float off,” Caldwell says. In the final 10-19 second, dark energy would rip individual atoms apart. Finally, it will tear the very fabric of space-time at the seams, marking the official end of the universe. The only solace is that life’s extinction would be quick and painless.
Scientists know too little about dark energy to determine with any certainty whether the universe’s fate is a Big Chill, a Big Rip, or neither. Caldwell and other cosmologists are studying distant supernovas to measure the universe’s expansion and explore the trend of dark energy’s influence over time. “We’re right on the dividing line between the Big Chill and the Big Rip,” Caldwell says. “The window of uncertainty includes both possibilities.”
THE LAST ESCAPE
Even in the most optimistic forecast, dark energy will eventually starve us of resources in a Big Chill, but that leaves us 10,000,000,000,000,000,000 years to perfect the most extreme survival strategy of all: escaping the universe before it chills, rips, crunches, bounces, or snaps into nothingness (yes, those are all scenarios that physicists have considered).
Starkman holds out hope that someone somewhere will figure out how to mine the remains of dead stars and generate energy: “We can do really well going from star to star, slowly consuming them.”
Many cosmologists now believe there are other universes hidden from our view—as many as 10500, according to string theory, a leading approach to unifying all the universe’s physical laws into one elegant solution. This past August, Greek and German physicists used string-theory equations to demonstrate that it may be possible to develop wormholes connecting our universe to another. With 10500 to choose from, at least one should be suitable for life.
Just don’t look to Starkman for how-to advice. Tunneling through wormholes to other universes apparently crosses his delicate line separating scientific prognostication from 2012 theology. “Now we’re really getting speculative,” he says.