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What Are Gravitational Waves? Why Should We Care About Gravitational Waves? Gravitational Waves For Dummies

Above: What Are Gravitational Waves? Gravitational Waves For Dummies.

The very first gravitational wave has been detected by LIGO, proving Albert Einstein’s Theory of Relativity. Where did this gravitational wave come from and what does it mean for the future of space science and astronomy? This article discusses why this scientific discovery is so important, what it means for astronomy, and what’s next for the future of space science and astrophysics.

What Are Gravitational Waves?

Gravitational waves are ripples in the curvature of spacetime that propagate as waves, generated in certain gravitational interactions and traveling outward from their source. The possibility of gravitational waves was discussed in 1893 using the analogy between the inverse-square law in gravitation and electricity. Predicted in 1916 by Albert Einstein on the basis of his theory of general relativity, gravitational waves transport energy as gravitational radiation, a form of radiant energy similar to electromagnetic radiation. Gravitational waves cannot exist in the Newtonian theory of gravitation, since Newtonian theory postulates that physical interactions propagate at infinite speed.

Gravitational wave astronomy is an emerging branch of astronomy which aims to use gravitational waves to collect observational data about objects such as neutron stars and black holes, events such as supernovae, and processes including those of the early universe shortly after the Big Bang. Various gravitational-wave observatories (detectors) are under construction or in operation, such as the Advanced LIGO which began observations in September 2015.

Potential sources of detectable gravitational waves include binary star systems composed of white dwarfs, neutron stars, and black holes. On February 11, 2016 the LIGO Scientific Collaboration and Virgo Collaboration teams announced that they had made the first observation of gravitational waves, originating from a pair of merging black holes using the Advanced LIGO detectors.

Introduction To Gravitational Waves:

In Einstein’s theory of general relativity, gravity is treated as a phenomenon resulting from the curvature of spacetime. This curvature is caused by the presence of mass. Generally, the more mass that is contained within a given volume of space, the greater the curvature of spacetime will be at the boundary of its volume. As objects with mass move around in spacetime, the curvature changes to reflect the changed locations of those objects. In certain circumstances, accelerating objects generate changes in this curvature, which propagate outwards at the speed of light in a wave-like manner. These propagating phenomena are known as gravitational waves.

Gravitational waves can penetrate regions of space that electromagnetic waves cannot. They are able to allow the observation of the merger of black holes and possibly other exotic objects in the distant Universe. Such systems cannot be observed with more traditional means such as optical telescopes or radio telescopes, and so gravitational wave astronomy gives new insights into the workings of the Universe. In particular, gravitational waves could be of interest to cosmologists as they offer a possible way of observing the very early Universe. Precise measurements of gravitational waves will also allow scientists to more thoroughly test the general theory of relativity.

Albert Einstein And His Search For Gravitational Waves

In 1916 Albert Einstein predicted gravitational waves, ripples in the curvature of spacetime which propagate as waves, traveling outward from the source, transporting energy as gravitational radiation. The first indirect detection of gravitational waves came in the 1970’s through observation of a pair of closely orbiting neutron stars. The explanation of the decay in their orbital period was that they were emitting gravitational waves. Albert Einstein’s prediction was confirmed on February 11, 2016 when researchers at LIGO published direct observation on Earth of gravitational waves, exactly one hundred years after the prediction by Albert Einstein.

Above: What Are Gravitational Waves? Why Should We Care About Gravitational Waves?

On Feb 11, 2016 scientists at LIGO announced that they had detected gravitational waves for the first time. In the press conference heard around the world, the LIGO scientists explained that two black holes had merged 1.3 billion light years away and had created waves that passed by the LIGO detectors and were finally heard. Albert Einstein predicted the existence of these waves in his 1915 theory of general relativity, but it took a long time for us to come up with the technology to detect them. For one thing, we had to invent lasers, so just in case you can’t tell, we are very excited about this great scientific discovery in astronomy and astrophysics.

What Is LIGO And Why Is LIGO So Important In Astronomy And Space Exploration?

The Laser Interferometer Gravitational-Wave Observatory (LIGO) is a large-scale physics experiment and observatory that was created to detect gravitational waves. LIGO is a joint project among scientists from several colleges and universities. Scientists involved in the project and the analysis of the data for gravitational wave astronomy are organized by the LIGO Scientific Collaboration which includes more than 900 scientists from around the world.

LIGO is funded by the National Science Foundation (NSF), with important contributions from the United Kingdom Science and Technology Facilities Council, the Max Planck Society of Germany, and the Australian Research Council. LIGO is also the largest and most ambitious project ever funded by the National Science Foundation. Livingston Louisiana hosts one of the two LIGO gravitational wave detector sites, the other one being located in Hanford Washington. In September 2015, LIGO detected the first direct gravitational wave observation which was reported in February 2016.

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