Quantum computers could herald a new age in electronics and society in general, and now a team of scientists believe they have uncovered a new tool to make it possible - contextuality.
University of Waterloo researchers in Canada, working in the Institute for Quantum Computing (IQC), studied the odd aspect of this theoretical technology.
Computer designers striving for a universal quantum computer have several hurdles that have to be overcome in order to make the devices possible. Waterloo physicists believe the concept of contextuality may be the breakthrough developers have been seeking.
"Quantum computers promise dramatic advantages over their classical counterparts, but the source of the power in quantum computing has remained elusive," researchers wrote in a journal article, detailing their development.
Quantum mechanics is a bizarre field of science, where few things are familiar, and the laws of nature can appear far different than that to which we are accustomed. One of the strangest aspects of quantum mechanics is the concept of contextuality. In our day-to-day world, scientists can measure properties like color, size and shape. But, in the tiny scales of sub-atomic particles, these observations are affected by the method, or context, one uses to view them.
One of the challenges involved in building a quantum computer is the amount of noise, or erroneous data that develops in the processor. A practice called magic-state distillation has been developed that could shield the devices. The process would also require "fault-tolerant" circuits that would recognize and reject false data.
But, these magic states are also contextual, the team realized. This idea could radically change how different processes are developed to manage noise within quantum processors.
"The result gives us a deeper understanding of the nature of quantum computation and also clarifies the practical requirements for designing a realistic quantum computer," Joseph Emerson, IQC researcher and co-author of the article announcing the findings, said.
Traditional computers operate on a binary basis - using ones and zeros to perform calculations. Quantum computers will use the odd laws of subatomic physics to be in more than one state at a time, through a property called superposition. Two or more particles can even be connected to each other through entanglement. When one of the members is altered, the other changes instantly. This could, one day, provide instantaneous communication across the Universe.
Contextuality and the behavior of sub-atomic particles may seem strange. But, one of the developers of the atomic bomb also had his own trouble with some of the strange concepts.
"If you think you understand quantum mechanics, you don't understand quantum mechanics," Richard Feynman is often credited with saying.
Discovery of the role of contextuality in quantum computing was published in the journal Nature.
