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.
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