You've probably heard the term "Quantum Computing" while scrolling LinkedIn, listening to a podcast, or watching a YouTube video. But when you think about it, it might not be very clear what it actually means. What capabilities can it provide in reality, and when will it be here?

To be honest, it'll take more than one blog post to go through each of these questions in detail (since the deeper you dive, the more questions you’ll have), but I'll try to give you some idea in this post.

Let's talk about a regular computer first. A computer, at its core, is a machine that’s really good at storing information and following a sequence of instructions. In our silicon based processors, we use transistors to store and process information in terms of 0s and 1s, where these values correspond to an actual physical state (like a switch being off or on). As part of the processing, the computer reads, writes, and performs operations, such as addition or multiplication, on the data to carry out tasks. Modern microprocessors provides us the capabilities to do these computations incredibly fast, allowing us to do amazing things in our day to day lives.

However, there are certain problems where the number of required bits increases considerably with the size of the problem. This results in an exponential increase in total possible states (there are $2^n$ possible states for $n$ bits). That means when we try to simulate something complex, like the behavior of molecules for drug discovery or new materials, the amount of memory and computation needed becomes enormous. This is one of the main reasons why simulating nature is so difficult for even our most powerful supercomputers.

Back in the mid 20th century, scientists realized that if we observe the microscopic world, the physics we knew couldn't explain what was happening (the dual nature of matter, the uncertainty principle, etc.). This is when Quantum Mechanics was developed. It is now considered one of the fundamental theories that describe our world, defining the structure, behavior, and interaction of atoms.

Later, scientists had the idea to use this theory to create systems that could exploit the "quantumness" of matter to achieve superior computational capabilities. In the following posts we'll talk more about "what these problems are" and "how we use them." But to give you an idea: certain specific problems can be solved exponentially faster on a quantum computer than on a classical computer. Active research in the field is currently focused on finding real world problems that could be solved faster using quantum computers. Simultaneously, researchers are figuring out how to build stable hardware, how to encode and decode information reliably, and much more.

I hope you enjoyed reading! It would be helpful to hear your feedback and, most importantly, what you would like to read about next.

If you want to learn more about this, you can listen to this podcast episode or read this article.