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Thursday, May 26, 2011

Out with a bang — new theory threatens to rewrite origins of universe

Out with a bang — new theory threatens to rewrite origins of universe

It all began, goes the prevailing theory of the origins of the universe, when the Big Bang set the cosmos in motion about 14 billion years ago, leading to the formation of the Earth nearly 10 billion years later and — if it all holds together for another day — to tomorrow morning's sunrise.

But a Canadian scientist and his British co-researcher, perhaps convinced that the end of Oprah doesn't yet seem insignificant enough in the grand scheme of things, have published a paper outlining the possibility that this universe is just one of many that have existed through infinite time, and that black holes — super-dense nodes of nothingness scattered across the expanse of space — could be key to proving their mind-bending theory.

Dalhousie University mathematician Alan Coley and University of London astronomer Bernard Carr have posted their essay — titled "Persistence of Black Holes Through a Cosmological Bounce" — at the arXiv online archive of scientific research studies.

The paper examines "whether black holes could persist in a universe which recollapses and then bounces into a new expansion phase," an idea that — if true — would explode, so to speak, the conventional idea that the Big Bang got our cosmic clock ticking around 13.7 billion years ago.

Others have kicked around the general notion before, Coley told Postmedia News, noting that the prospect of successive universal expansions and collapses — or "bounces" — represents an emerging field of interest in theoretical physics.

But "what we're bringing to the table," he said, is a proposed strategy for eventually testing "what possibly could persist from the previous epoch, and which would be something like a regular object. And the only things that could would be black holes."

Scientists believe that black holes — such profoundly compact celestial objects that even light cannot escape their gravity — have been formed throughout the life of this universe after heavy stars collapse and die in spectacular supernova explosions.

Some are also believed to have been formed in the midst of the Big Bang itself, and perhaps as the central hubs in the subsequent coalescing of galaxies.

But such objects could theoretically have been formed in prior universes and — because of their uniquely indestructible nature — may have survived the Big Bang to be studied today, Coley said.

And these so-called "primordial black holes," he explained, could have existed for hundreds of billions of years — in fact, from along any point in the infinite span of time before the birth of our universe — and "they wouldn't be destroyed in the Big Bang."

Coley said he and Carr are now preparing a more detailed study aimed at explaining how scientists might develop tests to determine the age of black holes and distinguish "younger" objects formed within the accepted time horizon of this universe and older black holes pre-dating the Big Bang.

The theory is "very speculative," he acknowledges, and that experiments testing it might be a generation away.

But he compares the quest to the way 19th-century geologists and other scientists, including Charles Darwin, pioneered new ways of interpreting rock layers and began to develop the idea that life actually evolved over "deep time" — millions and even billions of years — rather than appearing abruptly a few millennia ago, as suggested by the Bible.

"In geology, what happened was that as technology became more advanced, people's views became broader — you could put things in different perspectives and you could test things," said Coley. "In that sense, there's an analogy. But because this is theoretical physics, and it's right at the extreme, it's much more speculative."

While the Coley-Carr probe into the possibility of previous universes gives new meaning to the exploration of "deep time," other space scientists continue to investigate more "recent" phenomena, such as the birth of this solar system more than four billion years ago.

NASA announced this week that it would back an $800-million, Canadian-supported mission to retrieve rock samples from a distant asteroid and send them back to Earth for analysis by 2023.

The OSIRIS-Rex mission, which would include Canadian-made laser technology to guide an unmanned spacecraft on a four-year flight to the surface of asteroid RQ36, is expected to shed light on the Earth's origins because the space rock is considered an uncontaminated remnant from the formation of our immediate family of planets about 4.5 billion years ago.

"This asteroid is a time capsule from the birth of our solar system and ushers in a new era of planetary exploration," Jim Green, NASA's director of planetary science, said Wednesday.


AFP: NASA satellite 'helps find 17 Egypt pyramids'

AFP: NASA satellite 'helps find 17 Egypt pyramids'

WASHINGTON — Archaeologists have uncovered as many as 17 buried pyramids in Egypt with the help of NASA satellite imagery, according to a documentary to be aired by the BBC on Monday.

Led by US researcher Sarah Parcak at the University of Alabama at Birmingham, the team has already confirmed two of the suspected pyramids through excavation work.

The BBC, which funded the research, released the findings this week ahead of a broadcast describing the technique and what was uncovered.

"I couldn't believe we could locate so many sites all over Egypt," Parcak was quoted as telling the BBC.

"To excavate a pyramid is the dream of every archaeologist."

The team also found more than 1,000 tombs and 3,000 ancient settlements, according to the report.

Infrared images, which were taken by satellites orbiting 700 kilometers (435 miles) above the Earth, revealed the below-ground structures.

The satellites used powerful cameras that can "pinpoint objects less than one meter (three feet) in diameter on the Earth's surface," the report said.

The technology was helped by the density of houses and other buildings, made of mud brick so that they showed up somewhat clearly against the looser soil cover.

The documentary, "Egypt's Lost Cities," airs Monday on BBC One and will also be shown on the Discovery channel in the United States.


Mark Zuckerberg's new diet: Eating only what he kills - USATODAY.com

Mark Zuckerberg's new diet: Eating only what he kills - USATODAY.com

Facebook billionaire Mark Zuckerberg is always on the prowl for new ways to test himself.

So his "personal challenge" this year, he tells Fortune magazine, is to eat "only what he kills."

It started with the idea of being thankful for the food we have to eat.

"I think many people forget that a living being has to die for you to eat meat, so my goal revolves around not letting myself forget that and being thankful for what I have," he tells Fortune. "This year I've basically become a vegetarian since the only meat I'm eating is from animals I've killed myself. So far, this has been a good experience. I'm eating a lot healthier foods and I've learned a lot about sustainable farming and raising of animals."

His first kill was a lobster, which he had to throw in a pot of boiling water. "The most interesting thing was how special it felt to eat it after having not eaten any seafood or meat in a while."

But while he says he has "basically" become a vegetarian, he has experimented with killing bigger creatures. On May 4, Zuckerberg posted a note to the 847 friends on his private page: "I just killed a pig and a goat."

His friend Jesse Cool, a Silicon Valley chef, explains, "He cut the throat of the goat with a knife, which is the most kind way to do it."