The monstrous amount of processing power produced by computer manufacturers has not yet possessed the capacity to extinguish our hunger for computing speed and computing capacity. In 1947, American computer engineer Howard Aiken said that just six electronic digital computers would satisfy the computing needs of the United States. Others have made similar errant predictions about the amount of computing power that would support our growing technological needs. Of course, Aiken didn't count on the large amounts of data produced by scientific research, the growth and multiplication of personal computers or the emergence of the Internet, which have only fueled our need for more, more and more computing power.
Will we ever have the amount of computing power we need or want? In the event that, as Moore's Law states, the number of transistors on a microprocessor continues to double every 18 months, the year 2020 or 2030 will find the circuits on a microprocessor measured on an atomic scale. And the logical next step will be to create quantum computers and when possible, quantum computers for personal use, which will harness the power of particles to perform memory and processing tasks. Quantum computers have the potential to carry out specific calculations much faster than any silicon-based computer.
Scientists and researchers have already built fundamental quantum computers that can carry out certain calculations; but a practical quantum computer is still years away based on current developments. You don't have to go back much to discover the origins of quantum computing. While computers have been around for the majority of the 20th century, quantum computing was first hypothesized less than 30 years ago, by a physicist at the Argonne National Laboratory. Paul Benioff is credited with first applying quantum theory to computers in 1981. Benioff theorized about making a Quantum Turing machine. Most digital computers, such as the one you are using to read this article, are based upon the Turing Theory.
The Turing machine, developed by Alan Turing in the 1930s, is a hypothetical device that consists of a tape of unlimited length that is parted into little squares. Each square can either hold a symbol (1 or 0) or be simply blank. A read-write device reads these symbols and blanks, which gives the Turing machine instructions to carry out a specific task. Does this ring a bell? Well, in a Quantum Turing machine, the difference is that the tape exists in a quantum state, and so does the read-write device. This implies that the symbols on the tape can be either 0 or 1 or a superposition of 0 and 1; in other words the symbols are both 0 and 1 (and all points in between) at the same time. While a normal Turing machine can only perform one calculation or carry out one task at a time, a quantum Turing machine can perform many calculations and carry out many tasks at the same time.
Today's computers, like a Turing machine, function by controlling bits that exist in one of two states: a 0 or a 1. Quantum computers, however, aren't restricted to two states; they encode data as quantum bits, or qubits, which can exist in superposition (both 0 and 1). Qubits represent particles (atoms, ions, electrons or protons) and their respective control devices that are working in tandem to act as computer memory and a processor. Because a quantum computer can contain these different states simultaneously, it could possibly be millions of times more powerful than today's most powerful and fastest supercomputers. To give you an idea of how powerful that is, the world’s current fastest supercomputer is the Sunway TaihuLight, with a LINPACK benchmark score of 93.095 PetaFLOPS. One can only imagine how powerful quantum computers would be.
Quantum computers might one day be able to replace silicon chips, much the same as the transistor which once replaced the vacuum tube. Be that as it may, for the time being, the technology required for advancements and to develop such a quantum computer is beyond our reach. Most research in quantum computing is still exceptionally theoretical.
The most advanced quantum computers have not gone past controlling more than 16 qubits, proving that they are a far cry from practical application. Be that as it may, the potential remains that quantum computers could one day carry out, rapidly, easily and effectively, calculations and tasks that are unimaginably time-consuming and tedious in the case of conventional computers. A few key progressions have been made in quantum computing over the most recent couple of years. Let's take look at some of the quantum computers that have been developed so far.
1998: Los Alamos and MIT scientists figured out how to spread a single qubit across three nuclear spins in each molecule of a liquid solution of alanine (an amino acid used to analyze quantum state decay) or trichloroethylene (a chlorinated hydrocarbon used for quantum error correction) molecules. Spreading out the qubit made it more difficult to corrupt, enabling the scientists to use entanglement to observe and study interactions between states as an indirect method for examining the quantum information.
2001: Researchers and scientists from IBM and Stanford University successfully demonstrated Shor's Algorithm on a quantum computer. Shor's Algorithm is a way for finding the prime factors of numbers (which has an intrinsic part in cryptography). They used a 7-qubit computer to find the prime factors of 15. The computer correctly carried out the task and deduced that the prime factors were 3 and 5.
2005: The Institute of Quantum Optics and Quantum Information at the University of Innsbruck announced that scientists had made the first q-byte, or series of 8 qubits, using ion traps.
2007: Canadian startup company D-Wave showed a 16-qubit quantum computer. The computer solved a Sudoku puzzle and other such pattern matching problems. The company claimed it would produce practical quantum systems by 2008. Skeptics believe practical quantum computers are still a few decades away, that the system D-Wave has created isn't properly scalable, and that a lot of the claims made on D-Wave's Website are just impossible (or at least impossible to know for sure, given our understanding, so far, of quantum mechanics).
If practical quantum computers can be built, they will be extremely useful in factoring large numbers, and along these lines, important and valuable for decoding and encoding secret data. If a practical quantum computer was to be built today, none of the information that exists on the
Internet would be safe. Our current methods of encryption are as tiny as ants, compared to the complicated encryption methods possible in quantum computers. Quantum computers could also be utilized for easily searching large databases in a fraction of the time that it would take a conventional computer. Other applications could include using quantum computers to further study quantum mechanics, or even to help in designing other quantum computers. However, the fact that they could be so much powerful than modern supercomputers, they could turn out to be weapons of mass destruction. When practical quantum computers are close to being made possible, the data gathered from research and the developments at that time must be kept, to a particular extent, secret so that they might not fall into the wrong hands.
But quantum computing is still in its very early stages of development, and many computer scientists believe the technological advancements needed to create a practical quantum computer is years away. Quantum computers must have, at the very least, several dozen qubits to be able to take care of real-world issues, and thus serve as a very reasonable computing method.