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What’s all this buzz about quantum? Maybe you’ve heard it in science class or maybe in a sci-fi movie! No matter where you’ve come across it, you probably know it’s a bit strange, maybe confusing but also possibly an important part of the future. And all these things are true!

Physics is about using numbers to predict how things will move and interact. Just by going about your day, you have a sense of how balls will bounce or even how the Earth orbits the Sun. This kind of physics is called “classical”.

Quantum physics looks at the tiniest particles. At these scales our familiar classical physics breaks down and new effects pop up instead. These strange quantum effects tell us more about how nature works… and could help us invent new, powerful technologies – like quantum computers.

We think everyone can get their head around quantum, so we created a contest for adults to explain their favourite quantum effect using everyday language. Our expert judges picked the top 5 entries and this story from Nathan K. Long is one of them. Here he talks about “superposition” or how quantum particles can act like they are in two places at once:

Imagine a bee, we’ll call it a classical bee. The bee’s wings flap up and down, up and down, up and down. We know that the bee’s wings are either up or they’re down, or they’re somewhere in between. If you could slow down their motion and looked closely, you could see the wings rotating between the up and down position.

Now imagine a real bee. Can you tell if its wings are up or down? You can’t right? The wings almost seem like they’re both up and down at the same time! Hold that memory.

Now, let’s shrink the bee down so that it’s a tiny bee, we’ll call it a quantum bee. In the quantum world, the bee is still flapping its wings, but now we don’t know whether the bee’s wings are up or down (just like our memory). In this world, the wings are both up and down at the same time!

In the quantum world, we would say that the bee’s wings are in a superposition of being up and down. However, if we take a picture of the bee’s wings using a high-resolution camera, the picture will show the wings being either up or down!

When we observe the wings, their superposition collapses into either up or down in the quantum world. But if the bee’s flying around in the quantum world without being observed, then the wings are in that strange state between up and down, just like in our memory.

Did you know that the United Nations has declared 2025 as the International Year of Quantum Science and Technology? To celebrate, the Australian Institute of Physics, Cosmos and Double Helix Extra put on the Quantum Explained Challenge. We will be sharing more of the top entries from Challenge in the year to come. Stay tuned!