Chapter 7: Quantum Computing
Welcome to Chapter 7 of our Quantum Explainers Series! If you are inspired dive deeper into this topic, check out the Quantum Shorts Contest. You can take inspiration from this article (we will even hint at potential topics that you can make your video about) and provide your own take on quantum computing for the contest! Quantum research has many possible applications and quantum computing is one of them. Read about it below to learn more.
By Danilo Shchepanovich
April 14, 2024
Quantum computation is undoubtedly a large driver of interest for both fundamental and practical research in quantum science in the recent decades. How does a quantum computer work and how is it different than a classical computer? Will a quantum computers soon replace all classical computers? To answer this question, we’ll have to take a step back and delve into the basics of quantum computing.
Think of the device you're reading this on. It's powered by a classical computer, which uses countless tiny switches called transistors. These switches can either be on or off, representing the 0s and 1s of binary code. By flipping these switches through basic commands like NOT, AND, OR, and XOR, your device can perform calculations and run all the apps and programs you're used to.
Classical computers are great at breaking down complex problems into simple steps that involve shuffling these 1s and 0s around. By writing algorithms that take advantage of this binary logic, we can program computers to do just about anything from browsing the internet to playing video games.
Quantum computing takes the foundational principles of classical computing and extends them incorporate rules of quantum mechanics. Instead of the simple on/off switch, quantum computers use quantum bits, or 'qubits.' A qubit is simply a quantum object with two distinct quantum states. Because the state of the qubit is quantum, it exhibits phenomena such as quantum superposition and entanglement (see previous chapters).
If we take advantage of quantum superposition and entanglement in the algorithms we run on a computer that obeys quantum dynamics, it is possible to perform calculations exponentially faster than a classical computer could manage. For example, Shor's algorithm could theoretically crack the encryption codes that keep our digital lives secure while Grover's algorithm could search databases with a quadratic speedup. However, it is not easy to find clever algorithms where there is a quantum speedup and there is extremely active research in the field of quantum information science to invent and characterized such quantum algorithms.
Quantum information is also incredibly delicate. Any disturbance from the outside world can cause a qubit to lose its quantum properties, a problem known as 'decoherence.' It's like trying to balance a pencil on its tip; the slightest nudge can make it topple over. Despite these challenges, researchers are tirelessly working on ways to make quantum computers more robust. They're exploring new materials, error-correcting codes, and even entirely different models of quantum computing.
So will quantum computers replace your laptop? Not quite. Quantum computers aren't great at everything. They're specialized machines designed for specific tasks that classical computers struggle with. So, for the foreseeable future, quantum computers will work alongside classical ones, each playing to their strengths. As we continue to explore the quantum landscape, who knows what mysteries we'll unlock?