The doodles that changed the world

Scientific illustration: Copernicus and Galileo did it. Charles Darwin had someone else do it. Leonardo DaVinci, known primarily as an artist, also dabbled in it. Images have always been an important part of scientific understanding.

But in 1948, a simple doodle revolutionized theoretical physics. Around this time, physicists were struggling to understand quantum electrodynamics (QED) via calculations. Too often, their calculations gave 'infinity' as an answer, which wasn't useful. It felt like a dead end.

Richard Feynman used sketches to show concepts that didn't work as calculations alone, in a way that made it easier to understand. Feynman Diagrams, as they became known, show elements of space and time, and they allowed scientists to attach calculations to the elements of the image.

By giving us a storytelling format for the subatomic level, these diagrams helped change the way scientists saw fundamental interactions. From this, entirely new ways of exploring physics became possible.

How to read a Feynman Diagram

Even if you don't know much about physics, you can learn to read a Feynman Diagram. The two most important things to know are that you read them from left to right, and that in the diagram, time moves upward (think of an airplane taking off).

In the diagram below, you'll see two straight lines, representing electrons, and a squiggly line, which represents a photon, the smallest unit of electromagnetic radiation.

To read it, start at the bottom left, where the electron on the left releases a photon, and then follow it up and to the right. The photon is released and is received by the electron on the right, creating repulsion. And that's it.

Feynman Diagrams in the wild

Science requires imagination and creativity as much as any of the mathematical and scientific skills you're used to. And that's what Feynman diagrams capture so well.

They've inspired people like Edward Tufte, an artist and a pioneer in information visualization, whose admiration for their beautiful simplicity inspired a series of sculptures based on the diagrams. magination and creativity as much as any of the mathematical and scientific skills you're used to. And that's what Feynman diagrams capture so well.

Flyingvan Image byEdward Tufte via [www.edwardtufte.com]

Feynman was so excited about his diagrams that his own family van, a 1975 Dodge Tradesman Maxivan, was covered in them. That van was purchased by gaming entrepreneur Seamus Blackley in 2012, who set about restoring it. You might have seen the Feynman van in an episode of the Big Bang Theory.

Feynman van Image by Seamus Blackley via [www.symmetrymagazine.org/article/may-2014/saving-the-feynman-van]

You'll even see Feynman diagrams on things like t-shirts, mugs, and tote bags, where each doodle tells its tiny story. And these stories help us connect with the universe, from the very small to the very far away.