Gravitational waves

http://www.technologyreview.com/blog/arxiv/24114/

So there have been a few of these proposed, and some have been built on earth... to my knowledge, none have been done in space yet. Ok, first things first; what are gravitational waves and why are they important?

Gravitational waves are ripples in the fabric of space and time produced by violent events in the distant universe, for example by the collision of two black holes or by the cores of supernova explosions.

Quoting from the article: "The team says the observations should help them understand how galaxies and supermassive black holes evolve together, shed light on the physics of the early universe such as inflation as well as probing the nature of space-time, perhaps revealing quantum gravity corrections to classical gravity. It may even throw up some new sources of gravitational waves."

The "this applies to everything" theory... and yeah, it kinda does. It would be great to see how one coudl unify classical gravity to quantum gravity. Moreover, Einstein predicted them in his theory of general relativity, they are potentially a source of energy (just as ocean waves are on earth), they mesh/work with multi-dimensional theories, and seem to be essential to the unification theory.

How to detect these waves: basically, shoot a light across a long distance and see if it ripples, or strains under 'gravity'..

How one of these wave detectors looks on earth - The LIGO detector can see ripples in space from neutron stars...

And future projects: have detectors calibrated in space over much larger distances for greater sensitivity.

The NANOGrav team estimates the cost of its project over ten years to be a mere $66 million.

It expects to be up and running by 2020 and at that price looks remarkably good value. Of course, this will not happen on time or budget.