Quantum Entanglement Explained: (Part I) Superposition and Cats

Hi there. I’m assuming you’re reading this article because you want to know more about quantum entanglement. Recently, the Nobel Prize in Physics of 2022 got awarded to scientists who did research in this field, which is complicated but also very interesting if you ask me. So let’s dive right in!

Before we talk about quantum entanglement, here’s some more information about the Nobel Prize and the laureates of this year’s Physics Prize. The Nobel Prize is a global award given to those who have made achievements for humankind. It was proposed by Alfred Nobel in his 1885 will, with different categories, some of which got added later. These include the Nobel Peace Prize, the Nobel Prize in Physics, Nobel Prize in Chemistry, and the Nobel Prize in Physiology or Medicine, to name a few. The 2022 Nobel Physics Prize got given to Alain Aspect (France), John Clauser (U.S.A.), and Anton Zeilinger (Austria) for their work in quantum information science. The laureates of these prizes get a medal and a big paycheck, but more importantly, their work gets shared with the public and could inspire new ideas. So what are quantum information science and quantum entanglement?

The field known as quantum information science seeks to understand information transmission, processing, and analysis using quantum mechanics principles. Quantum entanglement, a fancy term sometimes known as “Spooky Action at a Distance,” would be crucial to having a much more efficient computer if scientists get it right. However, do be aware that it could also get quite confusing.

To further understand quantum entanglement and its benefits, you need to understand something else: How computers work. Generally, our computers and laptops use a system containing bits to store our information. A bit can be 1 or 0, and putting enough of them together would give you information. However, currently, we need to use transistors, or tiny on-or-off switches, to store that information as binary bits. Since we have a lot of information to store, scientists started making the transistor smaller and smaller, making hard drives more data-efficient. But even though we can make a transistor very small, it still takes up space, putting a physical limit on the capacity of information we can effectively store in an electronic device.

And then scientists discovered the “quantum bit,” or “qubit,” opening the door to new possibilities. The qubit could be an electron or particle and uses the system of 1s and 0s, but with a surprising benefit. At the quantum level, a qubit could theoretically exist as a “1” and a “0” simultaneously. That is known as a superposition. So you could have two outcomes of one qubit.

A famous example of quantum superposition is Schrödinger’s Cat, a thought experiment proposed by Erwin Schrödinger in 1935. It got made up of these parts: A radioactive element, a detector, a cat, and some poison, all put in a box. After you close the lid, there’s a 50% chance the element decays and gets detected, releasing the poison and killing the poor cat. However, there’s an equal chance all that wouldn’t happen, and when you open the box, you’ll see the cat still alive. Considering enough time has passed since you closed the box, the cat and all of this process get entangled together, known as quantum entanglement. Opening the box is like measuring the state of a qubit. Before seeing whether the cat is alive or dead, the cat would essentially be a zombie, with equal chances of both. That implies a superposition of the cat, the detector, and whether the poison got released.

Okay, so back to our quantum bits. Because qubits can be in a superposition, we can use them to our advantage. Quantum entanglement unlocks new possibilities for our computing methods since if two electrons get entangled into one, measuring the state of one also determines the state of the second electron, which would always be opposite the first. Since quantum entanglement reduces the steps needed to run an operation, it would mean faster computing methods for future quantum computers.

Next time, in Part II of this series, we’ll be looking at whether quantum entanglement enables multiple parallel universes to exist and more secrets of the universe. That’s the end of this production from the New News Newsminute. Thank you for reading, and please subscribe to not miss out on future updates.