This is a guest article by Mike Woods. I am always a sucker for a good article on technology -Simon (editor).
Ever since American Physicist Richard Feynman proposed the concept of a quantum computer at an MIT conference in 1981, the field of quantum computation has been largely speculative, with sporadic advances in the ensuing 30 years, mostly of the proof-of-concept type. But a few key recent advances suggest that the possibility of practical, working quantum computers may not be as far off as once thought.
A Quick Primer on Quantum Computing
Unlike a classical, digital computer, which encodes data into binary bits of information, a quantum computer exploits various physical properties of matter to perform computations that, in theory, vastly exceed the capabilities of even the most powerful, classical computers of present day. This is made possible by two very strange and counter-intuitive phenomena known as entanglement and superposition.
Entanglement: Two electrons, for example, are said to be entangled when a change in the physical state of one produces a simultaneous change in the other, with no passage of time, regardless of how far apart the particles are from one another.
Superposition: Electrons possess the property of â€œspinâ€, which simply refers the direction in which the particle is spinning, either clockwise or counterclockwise. Superposition is a state where the electron spins in both a clockwise and counterclockwise direction at the same time. These entangled superposition states are encoded into â€œqubitsâ€, the quantum mechanical version of a classical bit. It is the ability of qubits to exist two mutually exclusive states that, in theory, underlies the incredible power of quantum computers.
A classical computer, which encodes information in the form of binary bits simply cannot compete with a quantum computer, which encodes information in superposed states. To illustrate, say you need to match a set of fingerprints against a vast database of fingerprints. A classical computer would attempt to match the subject prints against the first set of prints in the database. If no match, it then proceeds to the second set, and then to the third, and so on, until a match is made or all possibilities exhausted. A quantum computer, on the other and, would compare the subject prints to ALL possible matches in the database AT THE SAME TIME. This is an order of magnitude better than what is presently possible with classical computers.
One Recent Advance
While there are several challenges to making a working quantum computer, one of the biggest has to do with preventing degradation of the quantum information by environmental factors, a phenomenon known as â€œdecoherenceâ€.
A recent achievement by physicist Viatsheslav Dobrovitski of the U.S. Department of Energyâ€™s Ames Laboratory and including researchers at the Delft University of Technology promises to overcome this challenge. Â Essentially, the team successfully isolated the solid state system from environment forces and at the same time maintained quantum coherence between the nucleus and electron in the system. This is a major step forward in the field of quantum mechanics.
Threats Posed by Quantum Computing
Two methods, RSA and elliptic-curve cryptography (ECC), form the basis of modern data encryption. Essentially, these data encryption methods exploit certain types of math problems that are so difficult as to be practically impossible to solve by present-day classical computers, even given billions of years!
Cryptographic Threat: A quantum computer, on the other hand, would possess sufficient computational power to solve these problems in mere minutes. This would mean that the worldâ€™s banking and financial system would be vulnerable to quantum threats, as would all military computer systems. The entire software industry would be affected since the registration keys would be breakable. Anything requiring a digital signature would be compromised. With many experts predicting the emergence of working quantum computers in as few as 10 years it is essential to understand these risks, and lay the groundwork for an effective counter-cryptography.
Intelligence Explosion: The Holy Grail of quantum computers lies in the realization of a true artificial intelligence (AI) that is capable of passing the Turing Test. For those of you unfamiliar with the Turing Test, it is a test of a machine’s ability to exhibit intelligence. A machine can is said to have passed the Turing test as soon as it displays a level of intelligence that is indistinguishable from that of a human being. Were this ever to be achieved it would mark a turning point in human history. As soon as any computer becomes as smart as the smartest human being, the machine could quickly design an even smarter machine. Taken to its logical conclusion, it would lead to an intelligence explosion as described by Ray Kurzweil in his highly influential book, The Singularity is Near. If that day ever comes, human intelligence will be left in the dust. Steps would need to be taken to ensure a friendly AI that worked with humans rather than against them. In other words, we must be careful the genie does not get out of the bottle.
The Hope of Quantum Computing
Impenetrable Networks: Quantum cryptography holds the promises to make computer networks so secure that they are impenetrable by outside parties. One such cryptographic method is known as quantum key distribution (QKD). This method allows two separate users to generate a secret key that can be used to encrypt and decrypt information. One very important aspect of quantum systems has to do with their sensitivity to outside influences. It has long been known that the mere act of trying to measure any aspect of the quantum system results in changes to the system. In other words, it is impossible to measure the system without changing the system. This property is exploited in such a way that allows of these cryptographic systems to detect when someone is trying to figure out the quantum key. In this way, such systems can be made completely safe from outside intrusions.
Other ways in which quantum computers could be used are in the area of modeling natural phenomena, such as the human brain, weather systems, earthquakes, nuclear explosions, chemical reactions and even financial markets to name a few. Itâ€™s hard to say what possibilities could be realized by being able to solve computational problem that are intractable to present-day, classical computers.
Like most powerful tools, it is human nature that decides whether they are used for constructive or destructive purposes. Quantum computing holds enormous potential in both regards. The time is now to prepare. The quantum future is already dawning.
Mike Woods is a freelance authorÂ whose interests include technology, politics and business. He is also Â a Central Indiana real estate broker specializing in Carmel homes for sale and real estate.