I recently heard about the future of computational power – quantum computing. I was instantly intrigued but also intimidated and confused. In this post, I will do my best to make this fantastic technological advancement easier to understand. Please forgive me if I struggle to explain quantum computing in layman’s terms; I’m neither a physicist nor a computer scientist.
What is quantum computing?
Quantum computers are programmed with different algorithms and require entirely different hardware than traditional computers. Instead of binary code, bits, and transistors, Quantum computers make calculations using quantum mechanics principles to process information. Uh oh, that didn’t explain anything at all. To understand that definition, it’s helpful to know what quantum mechanics is and its principles. ChatGPT says, “Quantum mechanics is a fundamental theory in physics that describes the behavior of particles at the smallest scales, such as atoms, electrons, and photons.” The three principles that I found most important to understanding quantum computing are qubits, superposition, and entanglement.
* Qubits: essentially the quantum version of a binary bit
* Superposition: the phenomenon that a qubit can exist in two states at the same time (both a 0 and a 1)
* Entanglement: when the state of one qubit correlates with the position of another (if you flip two coins, they will always land on the same side)
Instead of using traditional bits, quantum computers use qubits. For a basic understanding of quantum computing, you need to know that qubits are like bits but smaller and can encode more information. MIT clarified that qubits are subatomic particles, such as photons or electrons. The Department of Energy says about qubits “The laws of quantum mechanics allow qubits to encode exponentially more information than bits. By manipulating information stored in these qubits, scientists can quickly produce high-quality solutions to difficult problems.”
There is a phenomenon in quantum mechanics called superposition, where a qubit can exist in two states at the same time. This helps solve a limitation of our current computers, where a bit can only exist as a 0 or a 1. Instead of either being a 0 or 1, a qubit can be both at the same time; however once they “pick” a state once they are observed and measured. allowing the computers to solve multiple problems at the same time. The ability to make multiple calculations simultaneously speeds up the computational process exponentially. To get a final calculation, the qubits are measured, where they choose a state, either a 0 or 1.
ChatGPT explains entanglement as, “When qubits are entangled, the state of one qubit becomes correlated with the state of another, regardless of the distance between them.” This phenomenon confuses even the smartest of us, famously causing Einstein to say that it is “spooky action at a distance”. What we do know about it is that adding qubits increases its capabilities exponentially.
Why is this advancement even needed?
Traditional computers and even supercomputers can only solve problems up to a certain level of complexity. Quantum computing calculates problems that are too complex for our traditional computers. Older computers rely on transistor technology, meaning their total computational power correlates to the number of transistors used. Since we are approaching a minimum transistor size, we will eventually stop being able to improve computers be adding more transistors.
How will it be used?
To be clear, in 20 years, you probably will not be using a quantum computer. Traditional computers will have their place in our lives, as they’re relatively cheap, work for everything most people need, and are fairly simple machines. MIT says, “Using a classical machine will still be the easiest and most economical solution for tackling most problems.” However, for those who will be studying some of the world’s most complex problems, quantum computing may become a prominent factor in your life. Quantum computing will be crucial to gaining a better understanding of quantum mechanics itself. Still, more broadly, it can be applied to any physical systems that are quantum mechanical. These computers will be significantly better at solving optimization problems or picking the best option from a large set of options.
Here are the citations for the provided links:
1. IBM. (n.d.). Quantum Computing. Retrieved from [https://www.ibm.com/topics/quantum-computing](https://www.ibm.com/topics/quantum-computing)
2. SecurityWeek. (2024, February 7). Cyber Insights 2024: Quantum and the Cryptopocalypse. Retrieved from [https://www.securityweek.com/cyber-insights-2024-quantum-and-the-cryptopocalypse/#:~:text=Quantum%20computers%20use%20the%20additional,to%20provide%20their%20computing%20power](https://www.securityweek.com/cyber-insights-2024-quantum-and-the-cryptopocalypse/#:~:text=Quantum%20computers%20use%20the%20additional,to%20provide%20their%20computing%20power.)
3. U.S. Department of Energy. (n.d.). DOE Explains Quantum Computing. Retrieved from [https://www.energy.gov/science/doe-explainsquantum-computing](https://www.energy.gov/science/doe-explainsquantum-computing)
4. ASCR Discovery. (2023, April 1). Quantum Evolution. Retrieved from [https://ascr-discovery.org/2023/04/quantum-evolution/](https://ascr-discovery.org/2023/04/quantum-evolution/)
5. MIT Technology Review. (2019, January 29). What Is Quantum Computing? Retrieved from [https://www.technologyreview.com/2019/01/29/66141/what-is-quantum-computing/](https://www.technologyreview.com/2019/01/29/66141/what-is-quantum-computing/)
6. OpenAI. (n.d.). ChatGPT 3.5. Retrieved from [OpenAI’s website or relevant source].