Quantum computers are leaping ahead
The reality of the universe in which we live is an outrage to common sense. Over the past 100 years, scientists have been forced to abandon a theory in which the stuff of the universe constitutes a single, concrete reality in exchange for one in which a single particle can be in two (or more) places at the same time. This is the universe as revealed by the laws of quantum physics and it is a model we are forced to accept – we have been battered into it by the weight of the scientific evidence. Without it, we would not have discovered and exploited the tiny switches present in their billions on every microchip, in every mobile phone and computer around the world. The modern world is built using quantum physics: through its technological applications in medicine, global communications and scientific computing it has shaped the world in which we live.
Although modern computing relies on the fidelity of quantum physics, the action of those tiny switches remains firmly in the domain of everyday logic. Each switch can be either "on" or "off", and computer programs are implemented by controlling the flow of electricity through a network of wires and switches: the electricity flows through open switches and is blocked by closed switches. The result is a plethora of extremely useful devices that process information in a fantastic variety of ways.
Modern "classical" computers seem to have almost limitless potential – there is so much we can do with them. But there is an awful lot we cannot do with them too. There are problems in science that are of tremendous importance but which we have no hope of solving, not ever, using classical computers. The trouble is that some problems require so much information processing that there simply aren't enough atoms in the universe to build a switch-based computer to solve them. This isn't an esoteric matter of mere academic interest – classical computers can't ever hope to model the behaviour of some systems that contain even just a few tens of atoms. This is a serious obstacle to those who are trying to understand the way molecules behave or how certain materials work – without the possibility to build computer models they are hampered in their efforts. One example is the field of high-temperature superconductivity. Certain materials are able to conduct electricity "for free" at surprisingly high temperatures (still pretty cold, though, at well but still below -100 degrees celsius). The trouble is, nobody really knows how they work and that seriously hinders any attempt to make a commercially viable technology. The difficulty in simulating physical systems of this type arises whenever quantum effects are playing an important role and that is the clue we need to identify a possible way to make progress.
It was American physicist Richard Feynman who, in 1981, first recognised that nature evidently does not need to employ vast computing resources to manufacture complicated quantum systems...
http://www.guardian.co.uk/science/2012/may/06/quantum-computing-physics-jeff-forshaw
Although modern computing relies on the fidelity of quantum physics, the action of those tiny switches remains firmly in the domain of everyday logic. Each switch can be either "on" or "off", and computer programs are implemented by controlling the flow of electricity through a network of wires and switches: the electricity flows through open switches and is blocked by closed switches. The result is a plethora of extremely useful devices that process information in a fantastic variety of ways.
Modern "classical" computers seem to have almost limitless potential – there is so much we can do with them. But there is an awful lot we cannot do with them too. There are problems in science that are of tremendous importance but which we have no hope of solving, not ever, using classical computers. The trouble is that some problems require so much information processing that there simply aren't enough atoms in the universe to build a switch-based computer to solve them. This isn't an esoteric matter of mere academic interest – classical computers can't ever hope to model the behaviour of some systems that contain even just a few tens of atoms. This is a serious obstacle to those who are trying to understand the way molecules behave or how certain materials work – without the possibility to build computer models they are hampered in their efforts. One example is the field of high-temperature superconductivity. Certain materials are able to conduct electricity "for free" at surprisingly high temperatures (still pretty cold, though, at well but still below -100 degrees celsius). The trouble is, nobody really knows how they work and that seriously hinders any attempt to make a commercially viable technology. The difficulty in simulating physical systems of this type arises whenever quantum effects are playing an important role and that is the clue we need to identify a possible way to make progress.
It was American physicist Richard Feynman who, in 1981, first recognised that nature evidently does not need to employ vast computing resources to manufacture complicated quantum systems...
http://www.guardian.co.uk/science/2012/may/06/quantum-computing-physics-jeff-forshaw
