Consumer or Home computers started to appear in the late seventies and became “common” in the early eighties.
Ever since then, scientists have been working on making computers smaller and more powerful at the same time. Logically, we would ask: aren’t computers bounded by the speed of electricity traveling through the circuits composing these computers? well kind of, yes. That’s why go smaller. a smaller size circuit would mean less traveling time. but how much can we keep improving?
First, I’ll describe on a low level how a computer computes and outputs instructions. If you’re familiar with this process, go ahead and skip the next section.
Computing Basics
A computer, although seem to be very complicated, is actually made of simple components that have simple basic tasks that will allow it to process, control and represent data. These components are modules in the computer’s circuit. Their most basic form is what is known as “transistors”.
A transistor acts like a gate that either allows the current to pass through or blocks it. This translates to what is known as binary language. If the transistor allows the current to pass, it’s a 1. Otherwise, if the current is blocked, it’s a 0.
For the passing and blocking to make sense, a collection of transistors are bundled together to form what we call Logic Gates. Logic Gates imitate the work of logical operators. For example, an OR gate outputs a 1 (allows the current to pass) if one of its input is a 1; while an AND gate outputs a 1 (allows the current to pass) only if all of its inputs are 1. Otherwise, it would output a 0.
A set of Logic Gates can finally represent a meaningful output that would represent meaningful data. This allows us to add numbers, thus allowing us to multiply numbers, which finally leads to the ability for us to do whatever we want, anything that we currently do on our computers.
So a set of Logic Gates (knowing that each of them is a set of transistors) do the calculations of any required operation. This means the more Logic Gates we have, the more information the computer can process. That’s why scientists try to make smaller transistors every year. It is an attempt to fit more of them in the circuit and thus making computers faster.
According to Moore’s (co-founder of Intel) law, the number of transistors on a circuit doubles every two years. However, this law, knowing that it’s been “kinda” valid for the past years, is based on observations and predictions, but not on real science. We could be witnessing its end because until the day of me writing this post, the scale of a transistor has reached 5nm. To put this in perspective, the average size of an atom is 0.3nm. If the transistor size is to go smaller and smaller, at some point, we would reach a phenomenon called Quantum Tunneling. In other words, we would reach a phase where the current becomes irresponsive to the transistor and bypass it, even if the transistor is trying to block it. If that happens, computers won’t have the correct desired output of the logic gates and will stop being logical / stop making sense. This creates a physical barrier for Moore’s law and for the technological progress in computing.
To overcome such limitations, scientists are trying to exploit this quantum phenomenon in order to turn it from a limitation to a huge advantage. As a result, we were introduced to Quantum Computing.
Quantum Computing
Naturally, media and scientists talk about the amazing things that computers can do such as opening information to the world and making it searchable and easy to access, connecting people from across the globe, creating virtual realities, etc…
But what computers can’t do is rarely mentioned. We don’t mention how incapable they become when it comes to crunching big numbers that grow exponentially. An example of such problems: Imagine a classroom that contains 8 tables for 8 students and you have to assign a table for each student. Although the number of students is small, the number of possible configurations you have is 8! (eight factorial). That is 40,320 possible configurations!. Now if the principal comes and adds another table for one extra student, the number of possible configurations is now 9! (nine factorial) which equals to 362,880 possible configurations. 12 students? 479,001,600 possible configurations… Well, that escalated quickly! with every single addition, the number will grow in a remarkably huge way. This makes it really hard for a computer to process such tasks. For example, generating all the possible configurations for a class of 100…
Software engineers and mathematicians always try to find algorithmic tricks and shortcuts to make such calculations possible and more efficient. But the limitations still exist and will continue to exist. So… Quantum Computers to the rescue!
Unlike normal computers which usually transfer information in bits (either 0 or 1), Quantum Computers use Qubits (quantum bits) which can be a 0, a 1, or a superposition of a 0 and a 1 at the same time! This is extremely powerful because the ability to hold information can now grow exponentially as well! One Qubit can hold a superposition of two states (0 and 1) while two Qubits can hold a superposition of four states (00, 01, 10 and 11). 3 Qubits? 8 states, etc… A small show of perspective, 30 Qubits can store 1,073,741,824 values.
Not only Quantum Computers can transfer information in many forms at the same time, but it can as well process it simultaneously. To clarify that, let’s take an example of a problem composed of 4 bits. let’s pretend that its solution is 1011. An ordinary computer would have to try 24 combinations, turn by turn, such as:
0000 -> then, 0010 -> then, 0011 –> … etc until it reaches 1011.
On the other hand, a Quantum Computer would superposition 4 Qubits of 0’s and 1’s at the same time and tries all of the possibilities at the same time. Once it obtains a correct answer, a Grover operator sweeps away all the wrong answers and leaves us with the correct one.
Why should you care?
Quantum computing will impact every major industry: Finance, Logistics, Heath, literally every industry that has a significant amount of data that needs to be processed and / or searched through or needs information to be extracted from.
On its good side, Quantum Computing would be able to optimize any business by helping them explore and calculate new options and methodologies and workflows that they couldn’t previously decide on. It can also help the medical field by simulating DNA, enzymes, and molecules which is currently a huge limitation due to the limited processing power. If we could simulate them, it would help scientists and doctors understand our biology better, simulate experiments and come up with big advancements in the field!
However, on its evil side, Quantum Computing would be able to break all of the current internet’s security in seconds. This is achieved by the Quantum Computing’s parallel processing power and its efficiency in decrypting any encryption that uses any of today’s encryption algorithms. This would put all of the banking security and transactions, all of the sensitive information and social media accounts, pretty much everything at risk!
Conclusion
Quantum computers take advantage of Quantum Physics’ superposition property to calculate data at an exponentially growing rate and the entanglement property to calculate answers in a parallel mode. This makes quantum computers able to calculate problems that would take our current computers thousands of years to compute.
This gives Quantum Computing the power to change how many businesses and industries function. But the power given is greater than just that as Quantum Computing could bring all of our current security systems and measures to its knees, destroying every encryption algorithm created (at least until the day of writing this post).
Quantum Computing is still theoretical and is still in an early research state (again, at list till the day of writing this post). But big companies such as Microsoft, IBM, Google, Alibaba and others are heavily investing in this field to make Quantum Computing happen. We might see a fully operational quantum computing in our lifetime, but it won’t replace our current computers anytime soon.
Feel free to send a message if you had any thoughts, or questions regarding this topic, or share your thoughts by leaving a comment below.