Schrödinger’s cat saved from uncertain death -

Theoretical felines across the world breathed a sigh of relief with the news that Schrödinger’s cat has been given a reprieve from its nasty poisoning inside a box.

Scientists have discovered a method that will allow the extraction of information from quantum objects without destroying it upon detection, making new steps toward quantum computing.

Schrödinger’s test shows how atoms only take a definite quantum state once they have been detected, though once this happens the two simultaneously occurring states, called a superposition, collapse into just one definite value.

A team of researchers at the University of Massachusetts have proposed an experiment that would save one of the nine lives of the cat in Erwin Schrödinger’s famous thought test, by enabling scientists to detect the contents of the box without actually opening it.

A previous experiment saw a 40 micrometre long strip of piezoelectric material put into a superposition which responded to voltages to both contract and expand when a voltage is run through it.

The strip was forced into two states, enabling a superposition that was then destroyed upon inspection, something that the team is now trying to avoid.

They propose adding an electric charge to the wire to create an electromagnetic field around it, before plucking it two contrary directions.

This electromagnetic field can then be detected from outside the box, so to speak, by using an external sensor to work out how far the object is the wire is from its original position once it has been plucked.

This means that scientists would be able, for the first time, to gain a glimpse at Schrödinger’s kitty without having to call the theoretical RSPCA, as it does not involve direct detection and destruction of the simultaneously existing states.

"I extract information, but in a way that I don't learn too much," researcher Kurt Jacobs told the New Scientist.

"In our paper, the crucial thing is that the measurement does not destroy the coherence.”

What this means is that it offers a potential for quantum computing which would need to be able to detect the superposition states in order to open the exciting possibilities in this strange avenue of computer development.