Shell CEO: Resource Overload, Earth’s Challenges in 2050 from The Aspen Institute and The Atlantic on FORA.tv

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Toward the end of "The Amazing Spider-Man", Peter Parker saves a small child trapped in a car as the car is tossed from New York City's Williamsburg Bridge by the movie's villain, the Lizard. He does this by shooting a web of spider silk from a gadget on his wrist, catching the car mid-air and eventually, using the spider silk to reel the child back to safety.

To work, this technique relies on the strength of spider silk. And in mass quantities, spider silk is extraordinarily strong, stretchier than nylon and, pound for pound, stronger than steel cable. In other words, produced in mass quantities, it could, plausibly, dangle a car and child from a New York City bridge. That's according to Jim Kakalios, physics professor at the University of Minnesota and a science consultant for the film, which was released July 2012.

It's the elasticity of spider silk that makes this scene even more plausible, said Skip Garibaldi, professor of mathematics at Emory University. Elasticity means there's less "jerk" on the cars and the passengers trapped inside when they come to a stop. Of course, this all depends on Spider-Man bringing enough silk for the job.

"He needs a backpack of silk to do it," Garibaldi said.

When it comes to the science behind the fantasy, some superhero scenes fall shorter than others. Batman's cape, for example, lacks the wingspan to set the Dark Knight gently on the ground after leaping off a Gotham skyscraper. His hang glider cape would in reality shatter his knees, Kakalios said.

Sure, comic book superheroes have powers that transcend science. That's part of the fantasy. But Kakalios is committed to bringing science fiction closer to science fact. He volunteers through a program run by the National Academy of Sciences called the Science and Entertainment Exchange. The program helps match filmmakers with scientists on an as-needed basis. In July 2012, the group celebrated its 500th consult.

Some consultants are tapped for quick fact checks; others are part of the creative process from the beginning, like Kakalios and Spider-Man. Kakalios, for example, wrote the "Decay Rate Algorithm" equation for the filmmakers, who needed an identifiable formula to explain the research of scientist-turned-giant lizard Dr. Connors in the movie.

Kakalios has also turned his love of comic books into an introductory physics course called the Physics of Superheroes and has written two books on the subject. Watch Hari Sreenivasan's interview with him in the video above.

In the 1960's, writers began weaving more science into the story lines of comic books, after comics were accused of being too violent and lacking educational value.

When the Flash from the 1960's comic of the same name catches a bullet, he is operating under Einstein's Special Theory of Relativity, for example. Namely, by running the same speed in the same direction as the bullet, the flying bullet appears stationary to him, and he is thus able to grab it.

Superheroes get their facts wrong more often than right, Kakalios said. In "The Amazing Spider-Man" No. 9, Spider-Man calculates his centripetal forces correctly when swinging from building to building. But in the same comic, his understanding of physics lapses when he throws metal chairs into the air to "attract" the lightning produced by the villain of that comic, Electro. While metal is a good conductor, that doesn't mean it attracts electricity.

"That's as ridiculous as saying that water is attracted to drains," Kakalios said.

Here are some examples from Kakalios' book of other superheroes who got their science right, or close to it:

How the Invisible Woman Disappears

After a brush with cosmic rays, The Fantastic Four's Sue Storm develops the ability to turn transparent at will. Molecules in most of our cells absorb and re-emit light in the visible end of the spectrum. But there are cells in our bodies that are transparent to visible light, such as the lens of our eyes. Sunlight also contains light at shorter wavelengths, like ultra violet rays, that our eyes can't see. So the idea is that if Storm can change her cells so they absorb and reflect ultra-violet light while letting visible light pass through them, she would appear invisible to the naked eye, while she would still be able to see in the ultraviolet region of the spectrum.

Superman Knows His Electrical Currents

Superman didn't always have to fly or use his superhuman strength to intimidate his enemies. In his very first appearance in "Action Comics" No. 1, Superman attempts to scare information out of a crooked lobbyist by slinging the man over his shoulder and running across a telephone line and hopping over the grounded poles. The lobbyist protests that Superman will electrocute them both, but Superman knows that as long as he avoids making a connection to the ground, that they are in no more danger than the birds resting on the same wire. In order for an electrical current to move through the wires it needs to flow to a place with lower voltage -- like the ground. If Superman was touching the wire and the pole simultaneously, he and the lobbyist would complete the electrical circuit and all that current would certainly kill the lobbyist, if not the Man of Steel as well.

Catching Bullets is Easy if You're the Flash

The Flash can catch a speeding bullet by moving at the bullet's speed, Kakalios said. By increasing his velocity to match that of the oncoming bullet, it's reasonable that he could snatch it out of the air. It's the same reason you can pick up a ginger ale that's moving at 500 miles per hour -- when it's on an airplane. The relative velocity between the airline passenger and the beverage is zero, making pouring easy.

The Conservation of Momentum Kills Spider-Man's Girlfriend

In "The Amazing Spider-Man" No. 121, the Green Goblin knocks Spider-Man's girlfriend Gwen Stacy off of a bridge. Spider-Man catches her mid-fall with his web, but when he pulls her to safety she is dead. Kakalios says her death was the result of the conservation of momentum. When she is thrown from the bridge, her velocity increases due to gravity. By the time Spider-Man catches her 300 feet down, Kakalios estimates she is traveling at 95 miles per hour. That velocity goes from 95 miles per hour to 0 in the short time the webbing catches Stacy, creating the same results as a high-speed car crash -- too much force is needed to bring the 110-pound girl to a stop. If Spider-Man had slowed her deceleration gradually, the way a car's airbag slows you down over several milliseconds during a crash, she might have survived.

연설문 전문: 

Bill Clinton_State of the Union Address (February 4, 1997).txt

Walter Isaacson on Einstein from The Aspen Institute on FORA.tv

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Watch Tuesday, October 9, 2012 on PBS. See more from PBS NewsHour.

Adam Savage Presents Problem Solving: How I Do It from Maker Faire on FORA.tv

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Watch Monday, October 8, 2012 on PBS. See more from PBS NewsHour.

The bickering over islands is a serious threat to the region’s peace and prosperity

THE countries of Asia do not exactly see the world in a grain of sand, but they have identified grave threats to the national interest in the tiny outcrops and shoals scattered off their coasts. The summer has seen a succession of maritime disputes involving China, Japan, South Korea, Vietnam, Taiwan and the Philippines. This week there were more anti-Japanese riots in cities across China because of a dispute over a group of uninhabited islands known to the Japanese as the Senkakus and to the Chinese as the Diaoyus. Toyota and Honda closed down their factories. Amid heated rhetoric on both sides, one Chinese newspaper has helpfully suggested skipping the pointless diplomacy and moving straight to the main course by serving up Japan with an atom bomb.

That, thank goodness, is grotesque hyperbole: the government in Beijing is belatedly trying to play down the dispute, aware of the economic interests in keeping the peace. Which all sounds very rational, until you consider history—especially the parallel between China’s rise and that of imperial Germany over a century ago. Back then nobody in Europe had an economic interest in conflict; but Germany felt that the world was too slow to accommodate its growing power, and crude, irrational passions like nationalism took hold. China is re-emerging after what it sees as 150 years of humiliation, surrounded by anxious neighbours, many of them allied to America. In that context, disputes about clumps of rock could become as significant as the assassination of an archduke.

One mountain, two tigers

Optimists point out that the latest scuffle is mainly a piece of political theatre—the product of elections in Japan and a leadership transition in China. The Senkakus row has boiled over now because the Japanese government is buying some of the islands from a private Japanese owner. The aim was to keep them out of the mischievous hands of Tokyo’s China-bashing governor, who wanted to buy them himself. China, though, was affronted. It strengthened its own claim and repeatedly sent patrol boats to encroach on Japanese waters. That bolstered the leadership’s image, just before Xi Jinping takes over.

More generally, argue the optimists, Asia is too busy making money to have time for making war. China is now Japan’s biggest trading partner. Chinese tourists flock to Tokyo to snap up bags and designer dresses on display in the shop windows on Omotesando. China is not interested in territorial expansion. Anyway, the Chinese government has enough problems at home: why would it look for trouble abroad?

Asia does indeed have reasons to keep relations good, and this latest squabble will probably die down, just as others have in the past. But each time an island row flares up, attitudes harden and trust erodes. Two years ago, when Japan arrested the skipper of a Chinese fishing boat for ramming a vessel just off the islands, it detected retaliation when China blocked the sale of rare earths essential to Japanese industry.

Growing nationalism in Asia, especially China, aggravates the threat (see article). Whatever the legality of Japan’s claim to the islands, its roots lie in brutal empire-building. The media of all countries play on prejudice that has often been inculcated in schools. Having helped create nationalism and exploited it when it suited them, China’s leaders now face vitriolic criticism if they do not fight their country’s corner. A recent poll suggested that just over half of China’s citizens thought the next few years would see a “military dispute” with Japan.

The islands matter, therefore, less because of fishing, oil or gas than as counters in the high-stakes game for Asia’s future. Every incident, however small, risks setting a precedent. Japan, Vietnam and the Philippines fear that if they make concessions, China will sense weakness and prepare the next demand. China fears that if it fails to press its case, America and others will conclude that they are free to scheme against it.

Co-operation and deterrence

Asia’s inability to deal with the islands raises doubts about how it would cope with a genuine crisis, on the Korean peninsula, say, or across the Strait of Taiwan. China’s growing taste for throwing its weight around feeds deep-seated insecurities about the way it will behave as a dominant power. And the tendency for the slightest tiff to escalate into a full-blown row presents problems for America, which both aims to reassure China that it welcomes its rise, and also uses the threat of military force to guarantee that the Pacific is worthy of the name.

Some of the solutions will take a generation. Asian politicians have to start defanging the nationalist serpents they have nursed; honest textbooks would help a lot. For decades to come, China’s rise will be the main focus of American foreign policy. Barack Obama’s “pivot” towards Asia is a useful start in showing America’s commitment to its allies. But China needs reassuring that, rather than seeking to contain it as Britain did 19th-century Germany, America wants a responsible China to realise its potential as a world power. A crudely political WTO complaint will add to Chinese worries (see article).

Given the tensions over the islands (and Asia’s irreconcilable versions of history), three immediate safeguards are needed. One is to limit the scope for mishaps to escalate into crises. A collision at sea would be less awkward if a code of conduct set out how vessels should behave and what to do after an accident. Governments would find it easier to work together in emergencies if they routinely worked together in regional bodies. Yet, Asia’s many talking shops lack clout because no country has been ready to cede authority to them.

A second safeguard is to rediscover ways to shelve disputes over sovereignty, without prejudice. The incoming President Xi should look at the success of his predecessor, Hu Jintao, who put the “Taiwan issue” to one side. With the Senkakus (which Taiwan also claims), both Mao Zedong and Deng Xiaoping were happy to leave sovereignty to a later generation to decide. That makes even more sense if the islands’ resources are worth something: even state-owned companies would hesitate to put their oil platforms at risk of a military strike. Once sovereignty claims have been shelved, countries can start to share out the resources—or better still, declare the islands and their waters a marine nature reserve.

But not everything can be solved by co-operation, and so the third safeguard is to bolster deterrence. With the Senkakus, America has been unambiguous: although it takes no position on sovereignty, they are administered by Japan and hence fall under its protection. This has enhanced stability, because America will use its diplomatic prestige to stop the dispute escalating and China knows it cannot invade. Mr Obama’s commitment to other Asian islands, however, is unclear.

The role of China is even more central. Its leaders insist that its growing power represents no threat to its neighbours. They also claim to understand history. A century ago in Europe, years of peace and globalisation tempted leaders into thinking that they could afford to play with nationalist fires without the risk of conflagration. After this summer, Mr Xi and his neighbours need to grasp how much damage the islands are in fact causing. Asia needs to escape from a descent into corrosive mistrust. What better way for China to show that it is sincere about its peaceful rise than to take the lead?

Mark Greenblatt discusses the cover-up of inappropriate high school relationships.

Smile or Die: The Tyranny of Positive Thinking from The RSA on FORA.tv

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