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7 things you’ve got wrong about quantum physics

I have been popularizing quantum physics, my area of research, for many years now. The general public finds the topic fascinating and covers of books and magazines often draw on its mystery. A number of misconceptions have arisen in this area of physics and my purpose here is to look at the facts to debunk seven of these myths.

Don’t worry, you don’t need to know much about quantum physics to read this article. I will mostly be explaining what quantum physics isn’t, rather than what it is…

1. “Quantum physics is all about uncertainty”

Wrong! Quantum physics is probably the most precise scientific discipline ever devised by humankind. It can predict certain properties with extreme accuracy, to 10 decimal places, which later experiments confirm exactly.

This myth originated partly in Werner Heisenberg’s “uncertainty principle”. He showed that there is a limit to how accurately two quantities – for instance, a particle’s speed and its position – can be measured simultaneously. When quantum physics is used to calculate other quantities, such as the energy, or the magnetic property of atoms, it is astounding in its precision.

2. “Quantum physics can’t be visualized.”

Quantum physics describes objects that are often “strange” and difficult to put into pictures: wave functions, superimposed states, probability amplitude, complex numbers to name but a few. People often say that they can only be understood with mathematical equations and symbols. And yet we physicists are always making representations of it when we teach and popularise it. We use graphs, drawings, metaphors, projections, and many other devices. This is just as well, because students and even veteran quantum physicists like us need a mental image of the objects being manipulated. The contentious part is the accuracy of these images, as it is difficult to represent a quantum object accurately.

Working together with designers, illustrators, and video makers, the Physics Reimagined research team seeks to “draw” quantum physics in all its forms: folding activities, graphic novels, sculptures, 3D animations, and on and on.