If you've seen an animated movie in the last five years, you know that they are no longer the hand-drawn beauties of years past; they have a new beauty that's more diverse in style and tone, that's more precise and realistic and less painterly. That's because they're made on computers, using algorthims and physics, not sketches and painting. 

So if you've noticed that the way water moves or light travels, how a tree branches upward realistically, or snow falls as if it's real life, it's thanks to the incredible digital effects now available to animators. But as talented as anyone may be creating images for a film, there were still missing pieces to the creation process — until the scientists were called in. 

"The physics behind what's happening in these movies is incredibly complicated," Paul Debevec, a computer scientist and chief visual officer at the USC Institute for Creative Technologies," told the LA Times. "You need real scientists to understand what's going on."

And that's exactly what's happened. Over the last decade, leading researchers in biology, math and physics, former employees of NASA and other experts in fields far from the entertainment sphere have begun working with animation companies in Hollywood. Want to make animated fire look real? And make it look believable with characters moving in-between the flames or trying to douse them? Call a physicist.

Some of the scientists have gotten flak for leaving academia or research; but many of them are drawn by the interesting and specific challenges of working with visual media. And the paychecks are better too. 

Ron Henderson is a great example. A former high school math-whiz-turned-engineer trained at Princeton who spent years working on fluid dynamics, he left his job at CalTech and eventually became the director of the DreamWorks research and development team. He recently received an Academy Award for developing Flux, a fluid-simulation system, which creates high-resolution effects 100 times faster than in the past.

Other scientists are brought in to do what amounts to educational sessions with the animators — teaching the basics of the three laws of thermodynamics, showing them how bubbles work in 3D, how to draw a tree that looks like a real baobob (even if it talks in the movie), or designing imaginary vehicles. But it takes a physicist to make something fake seem real.

And that's what movies are all about. 

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Starre Vartan ( @ecochickie ) covers conscious consumption, health and science as she travels the world exploring new cultures and ideas.

Science goes Hollywood to make our movies more fantastic
Physicists work with animators to make what we see believable — and beautiful.