background preloader

Gravitational waves

Facebook Twitter

In physics, gravitational waves are ripples in the curvature of spacetime which propagate as waves, travelling outward from the source. Predicted in 1916 by Albert Einstein on the basis of his theory of general relativity, gravitational waves transport energy as gravitational radiation.

The existence of gravitational waves is a consequence of the Lorentz invariance of general relativity since it brings the concept of a finite speed of propagation of the physical interactions with it. By contrast, gravitational waves cannot exist in the Newtonian theory of gravitation, since Newtonian theory postulates that physical interactions propagate at infinite speed.

Various gravitational-wave observatories (detectors) are under construction or in operation, such as Advanced LIGO which began observations in September 2015.

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

Gravitational wave. Introduction. Effects of passing.

Sources of signal interpretation

Properties and behavior. Astrophysics implications. Detection. Mathmatics. In fiction. Gravitational waves carry the vast energy generated by black-hole mergers, star explosions and other dramatic events across the universe at the speed of light. Paul Sutter is a visiting scholar at The Ohio State University’s Center for Cosmology and AstroParticle Physics (CCAPP).

Gravitational waves carry the vast energy generated by black-hole mergers, star explosions and other dramatic events across the universe at the speed of light.

Sutter is also host of the podcasts Ask a Spaceman and RealSpace, and the YouTube series Space In Your Face. Sutter contributed this article to's Expert Voices: Op-Ed & Insights. Have you ever wanted to reach out from far away and just … slap someone? Usually, it’s pretty difficult, but if you’re both standing in some water, it’s not so hard. You slap the water, the water makes a wave, the wave travels to your adversary and it does the slapping for you. It doesn't have to be water, either. And you can do it in a perfect vacuum.

The key here is the nature of space-time. In general relativity, space-time is dynamic. Space-time isn’t a wooden floor; it’s a trampoline. Just like any other dynamic stuff, like water or air, space-time allows waves to travel through it. Gravitational Waves Detected by LIGO: Complete Coverage. Astronomers have directly detected elusive gravitational waves, 100 years after the existence of these spacetime ripples was first proposed by Albert Einstein in his theory of general relativity.

Gravitational Waves Detected by LIGO: Complete Coverage

Scientists with the Laser Interferometer Gravitational-Wave Observatory (LIGO) announced the find in a news conference today (Feb. 11). DISCOVERY STORY: In Historic First, Einstein's Gravitational Waves Detected Directly / Video Explainer You can watch the gravitational waves science update live online here. Gravitational waves are generated by the acceleration (or deceleration) of massive objects in the cosmos. There's convincing indirect evidence that gravitational waves exist, but a direct detection had proven elusive, until now. Read more about LIGO, gravitational waves, and what a direct detection means for astronomy, in's complete coverage below.

Thursday, Feb. 11. Gravitational waves – your questions answered. The final piece of Einstein's general theory of relativity, which has stubbornly evaded detection since his predictions a century ago, has been detected.

Gravitational waves – your questions answered

Scientists announced today at a press conference they’ve successfully picked up gravitational waves, formed during the cataclysmic collision and fusion of two mammoth black holes 1.3 billion light-years away. Not only does this confirm Einstein’s predictions, it gives astronomers a new method of “seeing” the Universe.

Nailing down gravitational waves – ripples through the fabric of space-time – has not been an easy task. Even Einstein was pessimistic about finding the miniscule vibrations. Indeed, in 2014 the astrophysics world was elated with the announcement that the Background Imaging of Cosmic Extragalactic Polarisation (BICEP2) telescope at the South Pole had picked up faint echoes of the Big Bang, only to have those hopes dashed when the signal turned out to be dust in our own galaxy. Gravitational Waves: 6 Cosmic Questions They Can Tackle.

The first direct detection of gravitational waves is now widely expected to be announced on February 11 by the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO).

Gravitational Waves: 6 Cosmic Questions They Can Tackle

Using LIGO's twin giant detectors—one in Livingston, Louisiana, and the other in Hanford, Washington—researchers are said to have measured ripples in space-time produced by a collision between two black holes. Such an announcement would vindicate Albert Einstein’s prediction of gravitational waves, which he made almost exactly 100 years ago as part of his general theory of relativity—but it would also have much further significance.

As vibrations in the fabric of space-time, gravitational waves are often compared to sound, and have even been converted into sound snippets. In effect, gravitational-wave telescopes allow scientists to ‘hear’ phenomena at the same time as light-based telescopes ‘see’ them. Do black holes actually exist? Gravitational Waves Explained. THE 2016 PHD Comics Calendar is here!

Gravitational Waves Explained

- Adorn your dreary lab or desk with this fun calendar designed by Jorge himself: Watch the new movie!