Sunday, March 25, 2001 By United Press International
Spanish and American astrophysicists claim the universe we inhabit contains an infinite number of other universes like our own, called O-regions, that we will someday be able to contact.
Jaume Garriga, of the University of Barcelona, and Alexander Vilenkin, of Tufts University, call the concept "many worlds in one."
As they explained to United Press International, these universes are likely similar to our own — share similar life forms, for instance — because they share a key feature with our world: a finite number of distinct histories. A history is the way something has evolved in time and will continue to evolve. Until now, physicists have never been able to make such an assertion.
The team will publish their hypothesis this fall in the journal _Gravitation and Quantum Cosmology_.
Are these ideas far-fetched? Alan Guth says no.
The Massachusetts Institute of Technology physicist told UPI, "Do I think that the ideas are viable? Definitely yes. In fact, I very much admire the precision with which the ideas are expressed. I consider the work of Alex Vilenkin and his collaborators to be the leading work in this field."
He explained, "What is new in their article is the realization that the total number of possible histories for each universe is finite."
An infinite number of universes like our own is a concept Guth — one of the foremost authorities on a concept called the inflationary universe — finds startling.
"That's a pretty mind-boggling conclusion," Guth told UPI from his Cambridge, Mass. office.
The idea that an infinite number of universes exist gives rise to some interesting, and troubling, implications.
"Whenever a thought crosses your mind that a terrible calamity might have happened," Vilenkin told UPI, "you can be assured that it has happened in some of the other O-regions."
Furthermore, since some O-regions have histories identical or nearly identical to our own, "if you nearly escaped an accident here, then you were not so lucky in some of the O-regions with the same prior history," he said
The worlds Garriga and Vilenkin imagine are not entirely calamitous, and may even be amusing.
"Distant copies of ourselves play all sorts of different roles" in these other worlds, Vilenkin said. In fact, "there are infinitely many O- regions where Al Gore is president and — yes — Elvis Presley is still alive!"
According to Vilenkin, Guth's work gave rise to the idea of many worlds in the first place. Guth formulated the now well-accepted idea that the universe is expanding — or inflating — and published the best-selling book _The Inflationary Universe_ in 1997.
As the visible universe expands, or inflates, it gives birth to new universes. Since inflation is eternal, new universe creation is also eternal.
"In an eternally inflating universe, anything that can happen will happen; in fact, it will happen an infinite number of times," Guth told UPI.
Guth also believes the many-worlds hypothesis has profound philosophical implications.
"We already know that our planet is merely a tiny speck in a vast cosmos, but now we are being told that we do not even hold a unique copyright on our own identities," Guth told UPI. "Instead, each of us is actually only a single copy of an infinite number of beings that are completely identical to ourselves."