## Computer History

For most of our history, human technology consisted of our brains fire and sharp sticks while fire and sharp sticks became power plants and nuclear weapons. The biggest upgrade has happened to our brains since the **1960s** the power of our brain machines has kept growing exponentially allowing computers to get smaller and more powerful at the same time. But this process is about to meet its physical limits computer parts are approaching the size of an atom to understand why this is a problem

## How does Traditional Computer work?

we have to clear up some basics a computer is made up of very simple components doing very simple things representing data.

The means of processing it and control mechanisms computer chips contain modules, which contain logic gates, which contain transistors, a transistor is the simplest form of a data processor.

in computers basically, a switch that can either block or open the way for information coming through this information. It is made up of bits which can be set to either 0 or 1 combinations of several bits are used to represent more complex information transistors are combined to create logic gates which still do very simple stuff

for example, an and gate sends an output of 1 if all of its inputs are 1 and an output of 0 otherwise combinations of logic gates finally form meaningful modules say for adding two numbers once you can add you can also multiply, and once you can multiply you can basically do anything.

Since all basic operations are literally simpler than first grade math you can imagine a computer as a group of 7 year olds answering ready basic math questions a large enough bunch of them could compute anything from** “Astrophysics to Zelda”**.

## What is the Transistor?

A transistor is just electric switch electricity is electrons moving from one place to another. So a switch is a passage that can block electrons from moving in one direction today a typical scale for transistors is 14 nanometers which are about eight times less than the **HIV virus** in diameter and **500 times** smaller than red blood cells. As transistors are shrinking to the size of only a few atoms electrons may just transfer themselves to the other side of a blocked passage via a process called **quantum tunneling**. In quantum real physics, works quite differently from the predictable ways we’re used to and traditional computers just stopped making sense.

## What is Quantum Computer and How is it works?

We are approaching a real physical barrier for our technological progress to solve this problem scientists are trying to use these unusual quantum properties to their advantage by building quantum computers in normal computers ** bits are the smallest units of information**. But

**which can also be set to one of two values a qubit can be any two-level quantum system such as a spin and a magnetic field or a single photon 0 and 1 of this systems possible states like the photons horizontal or vertical polarization in the quantum world the qubit doesn’t have to be in just one of those it can be in any proportions of both states at once this is called**

*quantum computers use qubits***superposition.**

But as soon as you test its value say by sending the photon through a filter it has to decide to be either vertically or horizontally polarized so as long as it’s unobserved the qubit is in a superposition of probabilities for 0 & 1 and you can’t predict which it will be but the instance you measure it.

It collapses into one of the definite States superposition is a game-changer for classical bits can be in one of two to the power of four different configurations at a time that’s * 16 possible combinations* out of which you can use just one for qubits in superposition. However, can be in all of those 16 combinations at once this number grows exponentially with each extra qubit twenty of them can already store a million values in parallel already weird and unintuitive property.

**Qubits **can have is entanglement a close connection that makes each of the qubits react to a change in the other state instantaneously no matter how far. apart this means that when measuring just one entangled qubit you can directly deduce the properties of its partners without having to look qubit.

Manipulation is a mind-bender as well a normal logic gate gets a simple set of inputs and produces one definite output a quantum gate manipulates an input of superpositions rotates probabilities and produces another superposition as its output. So a quantum computer sets up some qubits applies quantum gates to entangle them and manipulate probabilities and finally measures the outcome collapsing superpositions to an actual sequence of zeros and ones. What this means is that you get the entire lot of calculations that are possible with your setup all done at the same time ultimately you can only measure one of the results and it will only probably be the one you want. so you may have to double-check and try again. But by cleverly exploiting superposition and entanglement this can be exponentially more efficient than would ever be possible on a normal computer.

So while quantum computers will probably not replace our home computers in some areas they are vastly superior one of them is database searching to find something in a database a normal computer may have to test every single one of its entries quantum algorithms leads only the square root of that time which for large databases is a huge difference the most famous use of quantum computers is running IT security right now. you’re browsing email, and banking data is being kept secure by an encryption system in which you give everyone a public key to encode messages. Only you can decode the problem is that this public key can actually be used to calculate your secret private key luckily doing the necessary math on any normal computer would literally take years of trial and error, but a quantum computer with exponential speed-up could do it in a breeze another really exciting.

## Use of Quantum Computer in Daily life?

The new use is simulations of the quantum world are very intense on resources, and even for bigger structures such as molecules they often lack accuracy so why not simulate quantum physics with actual quantum physics quantum simulations could provide new insights on proteins that might revolutionize medicine right now we don’t know if quantum computers will be just a very specialized tool or a big revolution for Humanity we have no idea where the limits of technology.