How fast is your PC? May be 1.2 GHZ if you have the latest and fastest one. What about Supercomputers? How fast is world’s most powerful supercomputer? Capable to perform processing a couple of teraflops? Now let us take an example. If you are given a question- what times equals 21, then you probably answer the question that 7 times 3 or 3 times 7 equals 21 without blinking your eyes. But if you are given what times equal 617796 then to get correct answer, particularly if it is a combination of two unique numbers, you probably will forget to blink your eyes unless you posses super natural powers like Shakuntala Devi. It will take you about an hour or so to factor this 6-digit number. Now if you program your computer to factor these type of large numbers then what do you think it will take to factor say, a 125 digit number? Can you believe that our traditional network of fastest supercomputers performing only this dedicated factorization work may take months to get you right answer! You will also have to believe that to factorize a 1000 digit number, our most powerful supercomputer network will take Billions of years! This is where, our conventional computers gets defeated. Thanks to this deficiency of present day conventional computer, based on which, some security methods are devised and are being used presently in encryption techniques and file security systems. But when non-conventional computers such as Quantum computers are put for the same job (presently in theory), then the scenario will change dramatically and you have to throw away your existing security system involving cryptography in garbage can.
Need for non-conventional computers
What are non-conventional computers and why there is need for them? Well, no matter how fast conventional computers calculate, there will always be some calculations that are too large for them to complete in reasonable time. In fact, conventional computers cannot solve some certain types of problems in the lifetime of the universe. Secondly, they lack in field of Artificial Intelligent. Finally, the content of Internet is increasing exponentially, and one day it will be Impossible to get fairly accurate search results by conventional computers from Billions and Trillions of web pages as they will never be capable to perform full search at any given time duration no matter how fast they will be designed. To search an entry, conventional computer would take average n/2 tries whereas quantum computer will reduce the number of tries to the square root of n. Further; let us take an example of Amoeba. This single cell creature is fully capable to live and reproduce itself. In other words, this single cell has a computer with intelligent power built in that help this extremely small creature to live and reproduce even in very odd conditions. Scientist all over the universe are trying to devise Computers through chemical, biological or other means that can out smart the processing power of conventional computers, by all means i.e. in shape, size, power consumption and artificial intelligence. A Chemical computer is one that processes information by making and breaking chemical bonds and storing Logic states or information in the resulting chemical structures. Similarly, Biological Computers are possible as recent work proved that fragments of DNA could be used to compute the answer to complex graph theory problem. There are other possibilities in which Biochemical can be used in computing. A kind of light sensitive protein dye called Bacteriorhodopsin is said to be capable of providing very high density optical memory. This, if we can effectively integrate in our Electronic Computer in to a Hybrid circuit then we can build powerful computers having capacity many times more than our conventional computers.
Another area where Bio-Computing is seriously gaining momentum is Medicine. Efforts are on to synthesize drugs inside of cells. One day, the cells were made intelligent enough same as the case of Amoeba, that they will be capable to diagnose, travel to and treat the area of disease in your body. Imagine, with the help of new line of medicine, that are nothing but Bio-Computers, your headache will soon be a history.
Moor’s law is going to hit a size barrier in near future, when circuits cannot be devised beyond atomic level and thus more processing power cannot be obtained from conventional computers beyond a certain limit. The answer to those situations lies in non-conventional computers made by molecules. Molecular computers are constructed from molecular scale electronic devices that consist of only a few atoms and are constructed and interconnected by chemical means. The prototype of molecular computers are being devised on base of certain theory of Quantum Physics, hence are also known as Quantum Computers.
Working of Quantum Computer
In any matter, there are various particles such as electron, proton, neutron, positron etc. These particles moves or spins constantly in certain conditions. If the spins of these particles are controlled and if upward spin is treated as one and downward spin is treated as zero, then basic computing function can be carried over combinations of ones and zeros. As these very tiny particles spins at very high speed, the speed of computing also become very high. Practically, these particles can spin upward and downward at the same time, and hence are capable to solve the problems at the same time unlike the case with conventional computers that perform these operations in repeated cycle to solve these problems.
Our conventional computer use switches, gates and registers to manipulate and store binary digits 0 and 1, represented by ‘on’ and ‘off’ or ‘high’ and ‘low’ in electronic term. One bit of data is thus either 0 or 1. In Quantum computer, Quantum bits or ‘qubits’ is the superposition and entanglement, which is not limited to ‘0’ or ‘1’. Qubits, pronounced, as ‘cubits’ is the state of particle earlier shown as ‘on and off’ simultaneously. This simultaneous existence in many states is the power of quantum computer. How fast a quantum computer will be as compared to our traditional computer? Let us take an example. Our ordinary computer having say, 10 bits could exist in only one of 1024 states (that were formed by all the ten digit sequence made from 1 and 0) at each instant, means 1 calculation on one step. A quantum computer having 10 qubits could exist in all 1024 states at the same time. This means 1024 calculations at one step. In theory, a quantum computer can perform logic operations on 2n input in a single computational step. Whereas, to perform same task traditionally with our existing computers, either 2 n processors will have to work in parallel or the computation has to be repeated to 2 n times taking much more time. Now, we can imagine the power of quantum computer but only if it become reality in near future.
Hardware: the hardest part
Non-conventional computer in theory is possible and seems easy. But the practical part in devising hardware and designing them is really hard as of now. Input and output process and connecting to various devices electronically through hybrid means are really difficult and had to be addressed before thinking of any possibility in near future. For example, in quantum computing, it performs trillions of intermediate steps during computations. These steps can induce errors. Errors do occur in conventional computers, but reliable error correction technology is available here. But it is a long way to develop error correction technology to develop for quantum computers computing at tremendously high speed because they generate errors equally speedily and errors needed to be corrected at equal speed. You can imagine the difficulty in this example- presently on some prototype of quantum computer; researchers have to work on very delicate equipments where some of them are kept to nearly absolute zero temperature (several hundred below normal temperature)! In Bio-computers, technology to effectively connect living cells to electronic circuits is still in theoretical stage and is really the hardest part. However, in some areas, conceptual part has been cleared. For example, one research group has constructed a three qubits quantum system that has successfully executed the mathematical calculation 1+1=2. It will look ridiculous to you, but you have to start somewhere, and the point is, the quantum-computing concept has been proved experimentally.
Let us hope that if not in near future, than in a bit distant near future, we will have our non-conventional computer running in place of our desktop PC and Supercomputers. The real advantages of non-conventional computer will include-
- Dramatic reduction in size and power consumption in comparison to conventional ones.
- Super fast speed due to their smaller size and completely different computing technique.
- Possibility to surpass human body (parts of your body function without getting instructions from your brain, though connected through it) in storing data and computing capability.
- Building Artificial Intelligence comparable enough and may be better than human being.