LIGO and Virgo Join Forces In Search for Gravitational Waves

[C1ay]

The Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Virgo interferometric gravitational-wave detector of the European Gravitational Observatory (EGO) near Pisa, Italy, have agreed to join in a collaborative search for gravitational waves from sources in and far beyond our galaxy.

 

lefthttp://hypography.com/gallery/files/9/9/8/grav_waves_thumb.jpg[/img]The collaboration will link the three LIGO detectors, which are in the United States, and LIGO's partner, GEO600 in Germany, with the Virgo detector to increase the likelihood of detecting the elusive phenomenon first predicted over 90 years ago by Albert Einstein in his general theory of relativity, and pinpointing the source of the signals.

 

LIGO is funded by the U.S. National Science Foundation, Virgo is funded jointly by the Italian Istituto Nazionale di Fisica Nucleare (INFN) and the French Centre National de la Recherche Scientifique (CNRS) through the EGO Consortium, and GEO600 is funded jointly by the Max Planck Society in Germany and the Particle Physics and Astronomy Research Council in the United Kingdom. Peter Saulson of Syracuse University, spokesperson for the LIGO Scientific Collaboration, and Benoit Mours of the Laboratoire d'Annecy-le-Vieux de Physique des Particules, spokesperson for the Virgo Collaboration, guided the discussions that brought about this agreement. The LIGO and Virgo collaborations have collaborated in the past on more limited technical investigations, but this agreement is the first to involve full data sharing.

 

"This is a landmark agreement," Saulson says. "The members of both collaborations have overwhelmingly embraced this effort, recognizing that in spite of the hard work that it will take, the best science will come from collaboration."

 

LIGO, in the midst of a nearly two-year run functioning at its design sensitivity, is operating along with GEO600, while Virgo is making rapid progress toward its sensitivity goals. The agreement calls for data sharing to begin when the sensitivity and duty cycle of the interferometers allow a significant contribution to joint searches for gravitational waves. In the meantime, the two collaborations have begun to merge some of their data-analysis activities in anticipation.

 

Mours described the importance of this agreement. "Combining the data from the collaborations is a classic example of 'the whole being more than the sum of the parts.' The combined data will give us a much better chance of finding the first gravitational waves, and will allow us to have greater confidence in any detections. And, if we find something, the combined data will provide more information about the location of the source than either project alone could."

 

LIGO operates laboratories in Livingston, Louisiana, and Hanford, Washington. The project was designed and is operated by the California Institute of Technology and the Massachusetts Institute of Technology. Research is carried out by the LIGO Scientific Collaboration (LSC), a group of 500 scientists at universities around the United States and in eight foreign countries.

 

The LSC includes the members of GEO600, the German-British project that operates an interferometer near Hannover, Germany. Data from the GEO600 interferometer have been used in a number of observations by the LSC, and are expected to continue to play an important role in the global network once Virgo joins. Bernard Schutz, representing GEO, welcomes Virgo's participation. "With this agreement we are pioneering a closer level of scientific cooperation between the USA and Europe. By completely pooling our data and coordinating our operations we greatly improve the sensitivity of all our detectors and agree to share equally in the scientific results of our hard work. Science is the big winner from this agreement."

 

The Virgo Collaboration comprises 180 scientists from 13 institutions in France, Italy, and the Netherlands.

 

This agreement lays the groundwork for future expansion of worldwide collaboration. It explicitly states that new detectors are welcome to join the international network of gravitational-wave detectors as the new detectors become operational at a sensitivity that would benefit the collective scientific capabilities of the network.

 

The LIGO, GEO600 and Virgo detectors are very similar in concept, though many aspects of the apparatus have different detailed implementation. All projects have L-shaped facilities with multi-kilometer-long arms (4 kilometers for LIGO, 3 kilometers for Virgo, 600 meters for GEO600) with evacuated tubes that contain laser beams monitoring the positions of precision mirrors using interferometry. According to Einstein's theory, the relative distance of the mirrors along the two arms changes very slightly when a gravitational wave passes by. The interferometers are set up in such a way that a change in the lengths of the arms as small as one part in ten to the 18th meters (a thousandth the diameter of an atomic nucleus) can be detected.

 

The next major milestone for LIGO, Advanced LIGO, funded by the National Science Foundation with British and German partners, is expected to start construction in 2008. Advanced LIGO, which will utilize the infrastructure of LIGO, will be 10 times more sensitive than the current LIGO detectors. Virgo scientists are also planning for a comparable upgrade of their detector (Advanced Virgo), which will be made about the same time. Additional information about the detectors can be found at LIGO Laboratory Home Page Welcome — GEO600 Virgo

 

Source: Caltech

[HIENVN]

A discovery of gravitational waves is the wish of scientists around the world, but almost gravitational waves’ centers should not put a precondition for their scientists. The precondition “first predicted over 90 years ago by Albert Einstein in his general theory of relativity” should be a reason that scientists can not discover gravitational waves on the earth that I think these waves were found out since 1930’s.

The gravitational waves’ centers are uselessly spending the brainpower of their high-grade scientists.

[Tormod]

What is it you're trying to say, Hienvn? I don't understand. This article is mostly about scientific cooperation between two projects, involving many scientists.

 

The concept that LIGO builds on is truly fascinating. Discovery of gravitational waves would be a real scientific breakthrough.

[HIENVN]

What is it you're trying to say, Hienvn? I don't understand. This article is mostly about scientific cooperation between two projects, involving many scientists.

 

The concept that LIGO builds on is truly fascinating. Discovery of gravitational waves would be a real scientific breakthrough.

 

Please try to understand me, Tormod. This article introduce about scientific cooperation between two projects and the concept of many gravitational waves ‘ centers that I think I feel free when I say that concept is wrong.

I knew you are working for Einstein@Home, and you must believe on Einstein@Home. Why don’t you consider my opinion for a best of Einstein@Home if my opinion may have a little of right?

Discovery of gravitational waves would be a real scientific breakthrough, Thousands join hunt for gravitational waves - space - 14 March 2005 - New Scientist Space, but when do we discover gravitational waves in the 1916’s prediction of Einstein?

[HIENVN]

What is it you're trying to say, Hienvn? I don't understand. This article is mostly about scientific cooperation between two projects, involving many scientists.

 

The concept that LIGO builds on is truly fascinating. Discovery of gravitational waves would be a real scientific breakthrough.

 

I am sorry, Tormod.

I would like to tell you: “the 1916’s Einstein’s prediction for gravitational waves in 1915’s general relativity theory” is not enough to discover gravitational waves on the earth.

Scientists and technologists throughout the word are still looking for the presence of gravitational waves on the earth, based on the Einstein’s famous prediction of gravitational waves in 1916. Einstein used his general relativity theory in 1915 to explain that gravitational waves are a consequence of the movement of an object’s constituent particles.

Until now, all studies of gravitational waves on the earth have failed, because they were based on the prediction found in Einstein’s general relativity theory. The prediction in Einstein’s general relativity theory suggests that gravitational waves are the waves of a certain motion. Scientists and technologists will never confirm the existence of these gravitational waves if their research is based only on Einstein’s general relativity theory.

[InfiniteNow]

I am sorry, Tormod.

I would like to tell you: “the 1916’s Einstein’s prediction for gravitational waves in 1915’s general relativity theory” is not enough to discover gravitational waves on the earth.

You're right, they will probably need some sort of detectors. The distances involved when triangulating this are vast, and we'd need three measuring sticks spaced very wide apart.

 

 

LIGO Press & Media Kit: Fact Sheet

When they pass through LIGO's L-shaped detector they will decrease the distance between the test masses in one arm of the L, while increasing it in the other. These changes are minute: just 10-16 centimeters, or one-hundred-millionth the diameter of a hydrogen atom over the 4 kilometer length of the arm. Such tiny changes can be detected only by isolating the test masses from all other disturbances, such as seismic vibrations of the earth and gas molecules in the air. The measurement is performed by bouncing high-power laser light beams back and forth between the test masses in each arm, and then interfering the two arms' beams with each other. The slight changes in test-mass distances throw the two arms' laser beams out of phase with each other, thereby disturbing their interference and revealing the form of the passing gravitational wave.

 

[HIENVN]

You're right, they will probably need some sort of detectors. The distances involved when triangulating this are vast, and we'd need three measuring sticks spaced very wide apart.

 

 

LIGO Press & Media Kit: Fact Sheet

 

 

You’re right. Despite their best efforts, the scientists of gravitational waves' centers have not yet been successful in finding gravitational waves on the earth. To expedite the process of finding gravitational waves, the European Space Agency ESA ESA Science & Technology: Home page and the National Aeronautics & Space Administration NASA NASA - Home decided to work cooperatively on a program that they named LISA [Home Page] Laser Interferometer Space Antenna , which stands for The Light Interferometer Space Antenna. Their plan is to launch three satellites into orbit around the sun in 2017. These satellites will keep a constant distance between them and will communicate with the gravitational wave centers in order to detect gravitational waves from the universe, ESA Science & Technology: LISA.

However, LISA would not need to launch three satellites into orbit around the sun in 2017 (to discover gravitational waves) if their scientists study more for Einstein’s unified field theory rather than his general relativity theory. The nature of unified field theory will confirm gravitational waves are an exclusive kind of energy that scientists can discover these waves in their laboratories instead of in the universe.