Might be of some interest to some who enjoy slinkys... :-)

Original story at:

http://www.livescience.com/strangenews/090603-maco-entanglement.html

By Clara Moskowitz, LiveScience Staff Writer

Quantum entanglement is just spooky — even Einstein thought so. As if particles
(as in particle physics) have telepathic empathy.

The theory of quantum mechanics predicts that two or more particles can become
"entangled" so that even after they are separated in space, when an action is
performed on one particle, the other particle responds immediately. Scientists
still don't know how the particles send these instantaneous messages to each
other, but somehow, once they are entwined, they retain a fundamental
connection.

This bizarre idea riled Einstein so much he called it "spooky action at a
distance."

A new study found that this eerie quantum link can apply even to situations that
resemble the larger, everyday world. Scientists entangled two pairs of vibrating
particles separated in space, so that when one pair was forced to change its
movement, the other pair did as well.

"We've entangled something that has never been entangled before, and it's the
kind of physical, oscillating system you see in the classical world, just much
smaller," said John Jost, a physics graduate student at the University of
Colorado at Boulder, and a guest researcher at the National Institute of
Standards and Technology. Jost and team describe their findings in the June 4
issue of the journal Nature.

Previous experiments have entangled the internal properties of particles, such
as spin states, but this is the first time scientists have entangled the
particles' pattern of motion.

The breakthrough could help researchers build quantum computers, which could
theoretically make calculations much faster than existing technology.

"Apart from adding another toy to the quantum mechanic's playground, this is an
important tool for further developments in quantum-state engineering," wrote
physicist Rainer Blatt of the Austrian Academy of Sciences in a separate essay
in the June 4 issue of Nature. Blatt was not involved in the new study.

To achieve this feat of entanglement, Jost and colleagues set up two pairs of
ions (atoms with one electron removed, so that they have a positive charge).
Each pair included one beryllium and one magnesium ion, vibrating back and forth
toward and away from each other as if they were connected by an invisible
spring.

Using electric fields and lasers, the researchers herded the ions into separate
pairs and then entangled their motion. Then they separated the pairs by 240
micrometers (millionths of a meter), which is actually quite a span for an atom.
Even at this distance, when the researchers changed the motion of one pair —
stopped or started the vibrations — the other responded immediately, stopping or
starting in kind.

The experiment proved that this kind of everyday springy motion is
entangle-able, and blurred the boundary between the quantum world and the
regular macroscopic world we live in, where normal objects don't behave like
that.

As for why this entanglement, or any entanglement, is possible, physicists
aren't so sure.

"It's a very difficult question," Jost told LiveScience. "I would just have to
say that it stems from the laws and rules of quantum mechanics. There are a lot
of people trying to understand what it means."

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