‘Science Friday’ asks: What happens when science and Hollywood collide?

What’s better than “Science Friday,” the public radio call-in program that explores the microbiome, paleoforensics and comets, to name a few recent topics? How about a live show recorded at Caltech’s Beckman Auditorium with host Ira Flatow?

“If your’e looking for the other Ira, you’re in the wrong place,” Flatow warned the audience members before the tape started rolling.

They weren’t. These had turned out to watch Flatow investigate what happens when science and Hollywood collide. (If you’re going to do a live show in the Los Angeles area, odds are it will have something to do with the entertainment industry.)

Flatow talked with a veteran animator about how sophisticated computer graphics have revolutionized the movies. He moderated a panel with the writers behind the TV hits “The Big Bang Theory” and “Grey’s Anatomy” and the 2011 big-screen thriller “Contagion.” He asked one of the stars of “Avatar” how it felt to create a virtual version of himself. He reality-checked scenes from box office blockbusters. He even performed a stint as a game show host.

One of the guests was Sean M. Carroll, a theoretical physicist at Caltech. In his day job, he studies dark matter, dark energy and the origins of the universe. On the side, he also works as a consultant for movies and TV shows that want to make the science they portray seem realistic, if not 100% accurate.

Carroll shared a story about his work for “Thor,” a superhero movie from Marvel Studios. Thor’s home planet (Asgard) is flat, and the director envisioned a battle near the planet’s edge that would have sent at least one character plummeting over it to his death.

But Carroll objected. The only force that should have been acting on the unlucky character was the force of Asgard’s gravity – and that would pull a potential victim inward toward the planet, not push him away. Carroll made his concerns known to the studio’s top brass. The executives overruled the director and proclaimed that characters could not simply fall off the edge of their disk-shaped planet.

The movies don’t always get it right, of course. Even “Gravity,” which Carroll lauded for being “largely accurate,” got the physics wrong in one crucial scene.

After initially surviving a devastating impact with space junk, two astronauts (played by Sandra Bullock and George Clooney) had made their way to the International Space Station. They were connected by a parachute cord, but it was slowly unwinding itself from Bullock’s leg and the pair were drifting apart. Clooney urged Bullock to let him go – without his weight, he said, she would stand a better chance of making it back to the safety of the ISS. When she refused, Clooney unhooked his tether and floated away.

That would not happen in real life, Carroll said. In fact, since the pair were barely moving when he unclipped himself, Clooney should have simply stayed floating next to Bullock.

In Carroll’s view, the real shame wasn’t that the movie got it wrong, it’s that it missed a chance to do something that was both dramatic and scientifically accurate. Here’s how Carroll would have scripted the scene: Have Clooney shove Bullock toward the space station. Newton’s laws of motion would have handled the rest.

Earlier in the evening, Flatow and Dr. Zoanne Clack discussed a case in which a TV show was used to conduct a research experiment. The show was a 2008 episode of “Grey’s Anatomy” in which a pregnant woman with HIV learns that, with proper medical care, the chances of her transmitting the virus to her baby are only 2%.

That was a fact the Kaiser Family Foundation wanted to publicize, and it worked with the show’s writers to develop the plot line, said Clack, a writer and producer for the show. (She is also a trained emergency room physician and holds a master’s degree in public health.)

Before the episode aired, the foundation commissioned a survey of “Grey’s Anatomy” viewers and found that only 15% were aware that the risk of a mother passing HIV to her baby was so low. One week after the broadcast, that figure jumped to 61%. In a final survey six weeks after the show aired, 45% of viewers still retained the information, according to a Kaiser Family Foundation report. Considering that 17.5 million people watched the episode, about 5.25 million people learned something about HIV by watching the medical drama.

In another segment, Flatow spoke with USC computer graphics impresario Paul Debevec about the contraption he invented to convert real actors – like “Avatar” co-star and “Science Friday” guest Stephen Lang – into fully digital creations. Lang told Flatow that he liked his digital replica so much that he put it on his Twitter profile.

“I look much better digitally than I do in real life,” he said. Another upside is that he could dispatch his digital twin to make “Avatar” sequels while he did some television shows. But there is something about the computer-generated Stephen Lang that troubles the real Stephen Lang, and that is “the idea that I could do films 10 years after I’m dead,” he said. “I may actually go into porno, depending on who controls my rights.”

Segments featuring Flatow’s conversations about computer-generated imagery, writing about science for TV and film, and using technology to make digital doubles can be heard on this weekend’s “Science Friday” broadcasts. (You can also hear them on the show’s website.)

The entire production, including the quiz, is on this video – fast-forward to 1:40 (and keep an eye out for JPL’s Mohawk Guy, who volunteered to be one of the contestants). You can also watch KPCC’s Sanden Totten recount the ways in which Hollywood sci-fi writers anticipated the invention of flip phones, iPads and other real-world technology (that starts about 49 minutes in).

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