## The Evolution of Human Technology

For a long time, human technology was limited to our brains, fire, and pointed sticks. However, as time went on, these crude tools evolved into nuclear power plants and atomic bombs. Our greatest creations have always come from our brains. Since the 1960s, the power of our computers has exponentially increased, allowing them to become smaller and more powerful. However, we are now reaching the physical limits of this technological progress. The components of computers are approaching the size of an atom, which poses a problem. To understand why this is a problem, let’s delve into some key points.

### The Basics of Computer Components

An ordinary computer is made up of very basic components that perform simple tasks. These components represent data, the reasons for manipulation, and control mechanisms. Electronic chips are made up of modules that consist of logic gates, which are made up of transistors. A transistor is the simplest form of data processing in a computer. It acts as a switch that can open or close access to the data passing through it. This data is made up of bits, which can be either 0 or 1. Groups of bits are used to represent more complex information. Transistors are combined to form logic gates that perform simple actions. For example, an AND gate sends a 1 if all of its inputs are 1, otherwise it sends a 0. By arranging logic gates, modules can be created that can add numbers. Once you can add, you can also multiply. And when you can multiply, you can do anything. When all basic operations are simpler than first-grade math, you can think of a computer as a group of 7-year-old children answering simple math questions. A sufficiently large number of them can solve anything from astrophysics to Zelda.

### The Challenge of Shrinking Components

As **computer components **become smaller and smaller, quantum physics comes into play. In simple terms, a transistor is just an electrical switch. Electricity is the movement of electrons from one point to another. Therefore, a switch is a pathway that can block electrons from moving in one direction. Today, the average size of a transistor is 14 nanometers, which is 8 times smaller than the diameter of the HIV virus and 500 times smaller than a red blood cell. As transistors shrink to the size of a few atoms, electrons transfer themselves to the other side of the blockage through quantum tunnels. In the quantum realm, physics works differently, and traditional computers are a bit lost… (well, a lot lost). We are facing a true physical barrier to technical progress.

### The Rise of Quantum Computers

To overcome this problem, scientists are attempting to harness the unusual quantum property by creating quantum computers. In conventional computers, bits are the smallest unit. Quantum computers use qubits, which can be both 0 and/or 1. A qubit can have any value in the quantum system as it rotates in a magnetic field or a photon. 0 and 1 are the possible values and are represented by the vertical or horizontal polarization of the photon. In the quantum world, a qubit may not be in just one state, but in any proportion of the 2 states at the same time. This is called superposition. However, as soon as you test its value by sending the photon through a filter, the photon must be polarized either horizontally or vertically. So, as long as it is unobserved, it is in a superposition of probabilities between 0 and 1, and we cannot predict the result. The moment you measure it, the state of the qubit is defined. Superposition changes everything.

### The Power of Quantum Superposition

Classical 4-bit computers have 2 to the power of 4 different configurations, which makes 16 possible configurations, of which only one can exist. With qubits, thanks to superposition, they can have all combinations at the same time! This number exponentially increases with each additional qubit. Just 20 qubits can already have over 1 million possibilities in parallel. One of the strange properties that qubits can have is quantum entanglement. This includes the ability of each qubit to change states simultaneously, regardless of distance. This means that measuring 1 entangled qubit allows you to deduce the state of its partner qubit without looking at it.

### Manipulating Quantum Qubits

Manipulating qubits is also somewhat perplexing. While a normal logic gate has a defined number of inputs and produces a definite output, a quantum gate computes a superposition input, a probability of rotation, and produces another superposition. Therefore, a quantum computer applies quantum gates to entangle and manipulate probabilities to measure the output, transforming the superposition into a sequence of 0s and 1s. This means that you get a whole bunch of possible results with your arrangement all at once. In reality, you can only measure one result at a time, so you will likely have to retry until you get the right one. But by cleverly harnessing superposition and entanglement, quantum computing would be exponentially more efficient than any traditional computer.

### The Applications of Quantum Computing

While quantum computers will not replace our current computers, they are superior in certain cases. One such case is database searching. In order to search for something, a normal computer has to search through each of its files. However, a quantum algorithm only takes the square root of the time required in the previous case. This makes a huge difference for large databases. The most well-known use of quantum computers is in the field of computer security. Currently, online banking information is secured by an encryption system where you provide a public key to encode the messages that only you can decode. The problem is that this public key can be used to calculate your private key. Fortunately, performing all the necessary calculations would take years of failure, but a quantum computer with its superior speed could do it in an instant. Another interesting application is simulation. Simulating quantum systems is very resource-intensive, and even for larger structures such as molecules, we often have very little precision. So why not simulate quantum physics with quantum physics itself? Quantum simulation could shed light on the functioning of proteins and assist in medical research.

#### The Future of Quantum Computing

Currently, we do not know if **quantum computers** will be highly specialized tools or a revolution for humanity. We do not know where the limits of this technology lie, and there is only one way to find out: exploration and experimentation.