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Detection of gravitational waves would open new window on universe

AFP-JIJI

The rumored first-ever detection of gravitational waves would open a new window on the universe and its most violent phenomena.

Albert Einstein predicted their existence in his theory of general relativity 100 years ago. Einstein theorized that any object with mass bends space-time, much like a net bows under the weight of an object; movement by the object sends ripples through space-time like those in a pond when a stone is thrown.

The National Science Foundation, which has funded the hunt for these waves, said scientists will hold a news conference Thursday to discuss their results so far. Present will be scientists from the California Institute of Technology, the Massachusetts Institute of Technology and the Laser Interferometer Gravitational Wave Observatory (LIGO) who have been working on the detection of these waves for years. Simultaneous news conferences are scheduled at Paris’ National Centre for Science Research and in London.

The announcement of a news conference revived rumors that have been circulating in the scientific community for months that the LIGO team may have indeed directly detected gravitational waves for the first time.

The biggest waves in the fabric of space-time are produced when a massive object such as a black hole or a neutron star moves.

According to the rumors, the team may have observed gravitational waves produced by the collision and merger of two black holes.

Science magazine cited Clifford Burgess, a physicist at McMaster University in Ontario and a member of the Perimeter Institute for Theoretical Physics, as deeming the rumors credible even though he had not yet seen any documentation from LIGO.

The ability to observe these gravitational waves would offer astronomers and physicists a new way to look at the most mysterious workings of the universe, including the fusion of neutron stars and the behavior of black holes such as the giants at the centers of our Milky Way and other galaxies.

“The driving force of the universe is gravity,” said Tuck Stebbins, the Gravitational Astrophysics Lab chief at NASA’s Goddard Space Flight Center. “These waves are streaming to you all the time, and if you could see them, you could see back to the first one-trillionth of a second of the big bang.”

“There is no other way for humanity to see the origin of the universe.”

Stebbins said he believes “we stand at a threshold of a revolutionary period in our understanding, our view of the universe.”

The LIGO detectors — one in Washington and one in Louisiana — can “measure changes of space-time at the level of one-thousandth diameter of a proton,” he added.

Catherine Man, an astronomer at the Cote d’Azur Observatory in France, said the detection of these waves — if confirmed — would allow astronomers to probe the interior of stars and perhaps resolve the mystery of gamma rays, which are among the most powerful explosions in the universe and whose cause remains poorly understood.

“Now we are no longer observing the universe with telescopes using ultraviolet light or visible light, but we are listening to the noises produced by the effects of the gravitation of celestial bodies on the fabric of space-time, which could come from stars or black holes,” she said.

“And since the star or black hole does not stop these waves, which move at the speed of light, they come right to us, and we can therefore make models . . . to distinguish and detect their signatures.”

Two Princeton scientists won the Nobel Prize in physics in 1993 for discovering a new type of pulsar — a neutron star whose beams of radiation flash like a lighthouse as it rotates — that offered indirect proof of the existence of gravitational waves.

The LIGO team is collaborating with a French-Italian team on another detector, called VIRGO, that should become operational soon.