Sophisticated computers created to process large amounts of power have not yet succeeded in quenching our thirst for speed and computational capacity, which has continued to be developed. But looking at the history of computers, it seems difficult to believe what we have achieved at this time.
In 1947, American computer engineer Howard Aiken said that America only needed six digital computer units to meet the country’s computing needs. Meanwhile, other experts have made false predictions about the amount of costs that will support our growing needs.
What is a quantum computer?
The Turing Machine, which was developed by Alan Turing in the 1930s, is a theoretical device consisting of a tape tape of unlimited length that is divided into small boxes. Each square can have a symbol (1 or 0) or be left blank. The current literacy device will read these symbols and emptiness, which give the machine instructions for carrying out certain programs.
Now, in a quantum Turing machine, the difference is that the tape is in quantum, like the approval of the head of a literacy device. This means that the symbols on the ribbon can consist of 0 or 1, or superpositions 0 and 1; in other words the symbols are 0 and 1 (and all the dots here) at the same time. While ordinary Turing machines can only do one calculation at a time, a quantum Turing machine can do many calculations at once.
Today's modern computers, like the Turing machine, work by manipulating bits that exist in one of these two states: 0 or 1. Quantum computers are not limited to two states. Quantum computers encode information as quantum bits, or qubits, commonly found in superpositions. Qubits represent atoms, ions, photons or electrons and control devices that work together as computer memory and processors. Because quantum computers can hold many of these conditions and calculations together, quantum computers have the potential to be millions of times more powerful than the most powerful supercomputers available today.
How quantum computers work
Until now, the two most promising uses for quantum computer devices were to conduct quantum searches and quantum factoring. To understand how quantum search works, imagine if you search for specific names and telephone numbers in the Yellow Pages or telephone book in the conventional way. If the telephone book has 10,000 entries, on average you need to see about half of that number, which is 5,000 entries, before you have the potential to find the name and number you are looking for. The quantum search algorithm only needs to guess 100 times. With 5,000 guesses, a quantum computer is able to find 25 million names in the telephone book.
Quantum computers that exist today
One day, experts believe that quantum computers will replace silicon chips, just as transistors have replaced vacuum tubes. But for now, the technology needed to develop such quantum computers is beyond our reach. Most research in quantum computing is still very theoretical.
At present, the most advanced quantum computer's capabilities do not go beyond manipulating more than 16 qubits. That is, its capabilities are far different from practical applications. However, the potential of quantum computers can one day work faster and easier to do calculations that take up a lot of time on conventional computers. Some important advances have been made in quantum computing in recent years.
In practice, classical computers depend on the final level of principles, as explained by Boolean Algebra. Data needs to be processed under exclusive binary conditions at each time point or bit. Whereas at that time each transistor or capacitor must be at a state of 0 or 1 before changing the current status measured in billion seconds.
Quantum computers are tools that use principles derived from quantum theory in processing information. A quantum computer can process all kinds of information following the laws of quantum physics so that it can perform tasks by using all possible permutations at the same time.
Now, imagine what if the information in bits that were only "0" or "1" can be both "0" and "1" at the same time. Quantum computers take advantage of phenomena called superpositions, namely quantum phenomena that allow two different states to occur at the same time.
In the microscopic world, molecules, atoms, or electrons can behave very strangely and are very different from the macroscopic world that we can observe without a microscope. Objects in the microscopic world can be in two different states at one time. This is hard to imagine for those of us who are used to sensing things around us that can only be in one of two conditions at a time.
As an illustration, we can liken a lamp as an electron, then life and death of our lamp is compared to two electron states. In the microscopic world we can find this "quantum lamp" on and off at the same time.
Austrian physicist Erwin Schrödinger has an interesting tale about the phenomenon of superposition. He imagined a cat in an isolated box and connected to the quantum world. This Schrödinger cat while in the box is in two different circumstances at one time, namely life and death. Isn't that very strange and impossible in the macroscopic world that we usually see? But that's what the quantum world is like.
Quantum computers utilize the phenomenon of superposition in the calculation process. Instead of counting bits by bits or combinations of bits by bits at a time, a quantum computer can count simultaneously against many bits or combinations of bits at a time.
Physically, the quantum state in a quantum computer can be realized by small objects the size of molecules (10-10 meters) or smaller. For example, electrons have intrinsic properties resembling magnetic rods called spins. Like a magnet, electrons can point in one particular direction, up or down. These two opposite electron spin directions are like the "0" and "1" bits in a classical computer.
The quantum state of an ordinary electron spin is written as | 0〉 when pointing down, | 1〉 when pointing up, or a | 0〉 + b | 1〉 when pointing up and down all at once. Signs | 〉 Called "ket", is a mathematical representation of a quantum state.