Spotting the quantum tracks of gravity waves

By Aussiegirl

Here's another interesting article about perhaps the weirdest part of modern science, quantum entanglement. Don't be upset that this concept is so hard to understand -- it comes straight out of the mathematics, and I doubt that even the most brilliant physicist can truly visualize how a photon can be both a wave and a particle at the same time.

New Scientist News - Spotting the quantum tracks of gravity waves

Spotting the quantum tracks of gravity waves
27 May 2006
NewScientist.com news service
Zeeya Merali

THE spooky link that can exist between quantum particles even when they are far part could provide an unexpected way to detect the ripples in space-time known as gravitational waves.

Gravitational waves are set off by extreme events, such as supernova explosions, but they are weak and notoriously difficult to detect. Now a group of physicists is suggesting that the waves could leave their signature on "entangled" quantum particles lying in their path.

Entanglement is a weird quantum effect through which particles become intimately linked, so that measuring a property on one instantaneously affects the others, no matter how far apart they are. It is a fragile property that is hard to produce and manipulate, but this fragility may make entangled states sensitive enough to pick up the weak gravitational waves that have so far eluded other methods of detection. [....]

“A set of such entangled particles, with precisely defined spins, could be used to detect gravity waves”However, Lloyd does not think that a gravitational detector based on entanglement is a realistic prospect, even after amplification. "It's a real effect, but an unbelievably small one," he says. "To get something observable you'd need a gravity field so large it would rip your lab apart."