Posted on 11/07/2004 9:19:04 AM PST by PatrickHenry
You can breathe a sigh of relief: the Universe will last for at least the next 24 billion years, according to astrophysicists who have modelled the mysterious force of dark energy to work out the fate of the cosmos.
Andrei Linde, a theoretical astrophysicist from Stanford University, California, leads a team who previously predicted that the Universe might end as soon as 11 billion years from now1. But the team's latest research into dark energy, published online at the preprint server arXiv2, gives us a stay of execution.
The team's new calculation relies on recent observations from the Hubble Space Telescope3, which has found several supernovae that are moving away from us faster than any others seen before, implying that the Universe is expanding faster than we thought. Linde concludes that the Universe is likely to last for almost twice as long again as it has already existed, before collapsing back on itself in a 'big crunch'.
Deeply problematic
Astrophysicists were puzzled when they first noticed in 1998 that the Universe's expansion was accelerating. What could possibly counteract the gravity that drags massive galaxies together? Theoreticians suggested that some unseen force, dubbed 'dark energy', could be counteracting the pull of gravity. Many models describe dark energy as a negative pressure on the Universe: unlike a gas, the pressure of dark energy actually increases as it expands.
Unfortunately, dark energy has never been directly seen. "Even well educated guesses about dark energy are deeply problematic," says Robert Caldwell, an astrophysicist from Dartmouth College in Hanover, New Hampshire.
In Linde's model, which relies on calculations made by Yun Wang, a cosmologist from the University of Oklahoma, dark energy has two sources. One is a hypothetical form of energy produced by the seething mass of particles that spontaneously appear and disappear in a vacuum. The other is a type of force field that is intrinsic to the fabric of the Universe and continually drives its expansion.
"If we assume this model, the Universe will probably be safe for the next 24 billion years," Linde told news@nature.com.
Crunch or rip?
Physicists are still divided about the fate of the Universe. Some say it will keep expanding forever, whereas others believe that at some point in the future it will begin to contract and ultimately collapse in a big crunch. "All bets are off in terms of predicting the fate of the Universe," says Caldwell, who has previously suggested that the Universe could ultimately end in a 'big rip' as it expands into infinity.
"If I had to bet my money now, I'd say that for the next 10 billion years we will see exponential expansion," says Linde. "Over that time, you will be unable to distinguish the Universe from one that will expand forever."
But infinite expansion is just a cosmic illusion, according to Linde's calculations. "The duration of that expansion will ultimately be finite," he says, so that the Universe will end in collapse.
Only more observations will deliver progress on the problem, because astronomers are still unsure about how much the Universe's expansion has speeded up over time. The Supernova/Acceleration Probe (SNAP) could provide much needed data, says Linde. The craft was proposed by scientists at the Lawrence Berkeley National Laboratory, California, who want to study the light from hundreds of supernovae to track the rate of cosmic bloat, but the project is currently on hold.
Is that end day on a Wednesday?
Wouldn't want John Edwards to miss his Tuesday hair appointment.
I've got to hand it to scientists who always report using earth years as temporal measure. 24 billion years does sound better than 10 Universal minutes.
24 billion years...About the time it will take liberals to curse out Saddam, Arafat or Castro the way they curse out Bush.
the Universe will last for at least the next 24 billion years,
Earth is estimated to last another 5 billion years.
Man, conscious beings are the only known living thing that can understand nature to control nature. In 3,000 years of man's efforts to better understnad nature to control it there has been -- aside from the dark ages -- an ever increasing advancement of technology to benefit man.
We can't even imagine what technologies we'll have in a million years. Or even a hundred years. Most important is the increase in human longevity. There will come a time, sooner rather than latter where conscious man will reach youth rejuvenating biologic immortality on Earth.
Five billion years as way more time than it will take for man to create or travel to a another solar system to live.
Physicists are still divided about the fate of the Universe.
Five billion years is more than enough time to learn how to control nature to interdict the big crunch. The big crunch never happens. If not interdicted by conscious man on Earth then the big crunch has already been interdicted by conscious beings living among the billion of galaxies with a billion stars each. Immortal conscious beings that began their civilization five billion years prior to our Sun formed.
The three macro components of the Universe are mater, energy and conscious beings.
By then, we'll all be so old, we'll have forgotten why we want the universe to last, anyway.
Scientists realize the Las Vegas odds makers have a play in this. Bet the split.
I guess I've no more excuses, better get that report done.
...Women, Minorities Hit Hardest </NYT>
The lib's will never be able to wait THAT long!!
Well, that could ruin your day!
Oh, by the way, it's Bush's fault! :P
Hmmmm, hadn't thought of it that way before. O_O
As a physics student, I wonder if there is a way to tell if the universe has been "tampered" with.
After all, we model our physical theories based on what we see in the universe. But if what we see isn't what would occur naturally, then we'll always be wrong by some margin.
*scratches chin*
If it implodes, then the last person standing - please turn out the lights. If it continues to expand, then, never mind.
So now what do I do with all that Spam and toilet paper I stockpiled?
That's a relief. I have travel plans this Christmas.
But you better find somewhere to go for the last few billion years. Sounds like things are gonna be getting a little too cozy around here.
If the kids can be enticed away from their X-Boxes and Playstation 2 for long enough to do some actual work, earth can be converted to a sun-independent interstellar Winnebago.
As a physics student, I wonder if there is a way to tell if the universe has been "tampered" with.
There is. A person is working on it now. The gist of it is to know the parameters -- laws of physics -- that nature cannot escape abiding. Look for an anomaly that occurs outside the laws of nature.
An analogous example: a distant cousin to us Earthlings using a highly advanced telescope were to look at Earth and were to see the Hover dam that caused the Colorado river to back up to form Lake Mead they would know they were locking at an other than nature created structure. They'd naturally assume that it was created by conscious beings.
That method applies to viewing the cosmos. Search for cosmic events that fall outside nature's law.
Interestingly, evidence or proof may be sitting in the humongous mountains of data already stored on computers. It would require a massive effort to sift through that data and require asking different questions about it. A much quicker method is to create overlay charts.
See DemocRATS? No need to be all pouty. Surely you will win an election by then!
sun-independent interstellar Winnebago.
Priceless! :)
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