gravitational waves tagged posts

The National Science Foundation (NSF) has announced the detection of gravitational waves by the Laser Interferometer Gravitational-Wave Observatory (LIGO), a pair of ground-based observatories in Hanford, Washington, and Livingston, Louisiana. Albert Einstein predicted the existence of gravitational waves in his general theory of relativity a century ago, and scientists have been attempting to detect them for 50 years. He pictured these waves as ripples in the fabric of space-time produced by massive, accelerating bodies, such as black holes orbiting each other.

Just as in other areas of astronomy, astronomers need both ground-based and space-based observatories to take full advantage of this new window...

Stick with me and I’ll show you the universe. Artist’s impression of LISA Pathfinder. ESA, CC BY-ND

LISA pathfinder mission will prepare the way for us to study violent events that we’ve never seen before – such as the creation of massive black holes. The probe is to test technology needed to launch another mission, eLISA, in 2034, which will aim to detect gravitational waves. Intriguingly, the project may also help us prove some of the most extreme aspects of 3Einstein’s theory of general relativity.

Defn: General relativity states that gravity is just a manifestation of the fact that mass causes the surrounding space to curve, and it is the curvature of space that dictates the path followed by any other object, or indeed by light...

Columbia researchers predict that a pair of converging supermassive black holes in the Virgo constellation will collide sooner than expected. Above, an artist’s conception of a merger. CREDIT (P. Marenfeld/NOAO/AURA/NSF)

Astronomers have provided additional evidence that a pair of closely orbiting black holes deep in the Virgo constellation is causing the rhythmic flashes of light coming from quasar PG 1302-102. Based on calculations of the pair’s mass – together, and relative to each other – the researchers go on to predict a smashup 100,000 years from now, far sooner than previously predicted. The collision will be so powerful it would send a burst of gravitational waves surging through the fabric of space-time itself.

Spiraling together 3...

Because quantum motion, or noise, is theoretically an intrinsic part of the motion of all objects, Schwab and his colleagues designed a device that would allow them to observe this noise and then manipulate it. The micrometer-scale device consists of a flexible aluminum plate that sits atop a silicon substrate. Credit: Chan Lei and Keith Schwab/Caltech

For the 1st time, Caltech and other researchers have found a way to observe and control quantum motion of an object that is large enough to see. Even large objects obey quantum physics, ie they are never quite at rest.
In classical physics, physical objects indeed can be motionless. Drop a ball into a bowl, and it will roll back and forth a few times, then gravity and friction will cause the ball to come to a stop.

“In the past couple of yea...