Noah Haggerty | (TNS) Los Angeles Times
LOS ANGELES — A mind-bending hypothesis is gaining traction among scientists: The universe may be teeming with microscopic black holes the size of an atom, but with the mass of a city-sized asteroid.
Created just a split second after the Big Bang, these hypothetical black holes would whip quietly through the solar system roughly once every few years, traveling over a hundred times faster than a bullet.
Some have even argued that an immense explosion that flattened a Siberian forest in 1908 could have been the result of one of these micro black holes impacting Earth.
Now, researchers say they’ve figured out a way to test whether these cosmic bullets truly exist.
In a study published Tuesday in the journal Physical Review D, physicists at MIT say the presence of a tiny black hole speeding through the solar system could be identified by the gentle gravitational nudge it exerted on the Earth and other planets, which would alter their orbital paths by no more than a few feet.
The possibility of proving the existence of micro black holes is generating excitement among some astrophysicists because it could help them to explain a mystery that has taunted them for almost a century: the nature and composition of dark matter.
In the 1930s, astronomers started noticing anomalies in the way galaxies were moving. Lurking in the dark and empty expanse of intergalactic space, something was generating tremendous amounts of gravity to tug on the galaxies — yet it seemingly refused to interact with light or any other force.
Scientists found this mysterious gravitational tugging everywhere. In order to account for it, they hypothesized that it was being caused by invisible mass, or dark matter, that made up roughly 85% of all matter in the universe.
Some physicists have suggested dark matter may be made up of exotic undiscovered particles. Others, such as the MIT researchers, think dark matter probably is just regular matter that is extremely hard to detect. And black holes, the researchers say, are a prime example of the properties of dark matter.
“It’s just fantastic that the most conceptually conservative response is to say, ‘It’s just super tiny black holes that were made a split second after the Big Bang,’” said David Kaiser, a physics professor at MIT and an author on the study.
“It’s not inventing new forms of matter that have not yet been detected. It’s not changing the laws of gravity,” he said.
Still, black holes are not the sole potential culprit and there remains a lot of debate in the field.
Physicists have, in their quest to find dark matter, searched for new exotic particles, as well as regular matter that may have been overlooked — such as black holes of varying sizes. So far, they have come up empty-handed.
Until now, astronomers have been unsure how to search for black holes of a particularly pesky size — those that are too small for their gravity to bend star light.
The MIT researchers determined, through modeling, that these tiny black holes …read more
Source:: The Mercury News – Entertainment
