Physics of Quantum computing

Lets try to understand this together.

The physics of how a quantum computer works is complex and interesting. Before we go too far into detail about how it works, let’s discuss how we are pushing classical computers to their limit. In a classical computer there is something called a transistor. What a transistor does is control the flow of electrons. In this day in age there are companies working on 7 nanometer transistors. To put this in prospective a human hair is about 100,000 nanometers wide. . . that is .00007 percent of a human hair. As these transistors get smaller and smaller the electrons start pass through the transistor not caring if the light is red or green (example above), which is a small problem (pun intended). As transistors get smaller and smaller, they need to start following the rules of the quantum world, this entails the creation of quantum computers. As discussed, earlier quantum computers use something called a qubit. Qubits use any two-level quantum system. A qubit can be in either state of these two-level quantum systems (represented by 0 or 1) as we discussed earlier, this is called superposition. Once a qubit is measured it leaves the superposition state and becomes either a 0 or a 1. Superposition is powerful because the number of configurations grows exponentially compared to a classical bit. What I mean by this is if you had 8 bits there is only one possible outcome. In our case the outcome will be 00001111, where as a qubit can be all 256 of possibilities (click here). Fun fact, I wrote a program specifically to gather all possible states for a qubit. As you can see using quantum physics can increase our computing power exponentially.