Physics flies off the rails in 'Unstoppable'

It’s a gripping premise: “1 million tons of steel. 100,000 lives. 100 miles to impact.”

The new movie “Unstoppable,” features a runaway train, loaded with toxic chemicals, speeding towards a town with a bend in the tracks. It’s actually loosely based on a 2001 incident when a renegade locomotive was halted just short of Kenton, Ohio.

But is the science in “Unstoppable” accurate? Could the train’s impact decimate a town?

Emory physicist Sidney Perkowitz applies the basic formula of kinetic energy – one-half the mass times the speed squared – to compare the impact of the “Unstoppable” train to nuclear bombs and an asteroid.

A hydrogen bomb carries energy equivalent to 20 million tons of TNT. A train weighing one million tons, traveling at 50 miles per hour, as the movie’s publicity describes it, would carry the equivalent of 60 tons of TNT. “That would be a major explosion,” Perkowitz says.

But can a train really weigh 1 million tons?

“I think whoever wrote the publicity forgot the difference between tons and pounds,” Perkowitz says. If the train had a weight of 1 million pounds, then it would only have the energy of 60 pounds of TNT.

“That’s certainly enough to take out a building,” he says. “It would turn an SUV into molecules and it would be a terrible crash, but not enough to take out a whole city block.”

Interesting science, but not likely to stop movie goers in their tracks. “It sounds like a fun film,” Perkowitz says. “I would sit back and munch some popcorn and let the train run over me, and not worry too much about the math.”

Check out this video of Perkowitz talking about the physics in the movie “Iron Man,” and how it has some basis for reality in the U.S. military.

Sound too far-fetched? Watch this news video from CNN, below, about a half-man, half-robot contraption developed by the defense contractor Raytheon:

Are astronauts at risk for lung cancer?

NASA photo

Researchers from Emory's Winship Cancer Institute and the Medical College of Georgia are launching a new cancer research initiative – into space.

NASA awarded a team of investigators from both institutions $7.6 million to study how space radiation may induce lung cancer. The award establishes a NASA Specialized Center of Research (NSCOR), consisting of a team of scientists with complementary skills.

Interplanetary space travel could expose astronauts to conditions where they are chronically exposed to types of radiation not normally encountered on earth. One of these is high energy charged particles (HZE), which results in complex damage to DNA and a broader stress response by the affected cells and tissues.

There is no epidemiological data for human exposure to HZE particles, although some estimates have been made studying uranium miners and Japanese atomic bomb survivors, says Ya Wang, a radiation oncologist and director of the NSCOR at Emory.

Animal experiments show that HZE particle exposure induces more tumors than other forms of radiation such as X-rays or gamma rays. Because it is a leading form of cancer, lung cancer can be expected to be prominent among increased risks from radiation even though astronauts do not smoke. However, the risk for astronauts remains unclear because the dose of HZE astronauts are expected to receive is very low, Wang says.

Read more in this Winship news release.

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Ditch the guilt and be happy

Mary Loftus, associate editor of Emory Magazine, describes the top 10 things that religious leaders say about happiness in the Huffington Post:

One of the things that most irritated me about Sunday school -- and there were many, including the fact that I had to wear tights, keep quiet and not ask why God wasn't a girl -- is that we were told, however covertly, that happiness was selfish.

Religion, I came to believe, was all about self-sacrifice. How could we be happy when babies in Angola were starving (or being sent to purgatory by the Pope)? How could we be happy when already we bent so readily toward sin? How could we be happy when we had to constantly be on guard against greed, pride, sloth, lust and gluttony (i.e., cool stuff, bragging, hanging around, casual sex and cookies)?

Come to find out at a recent "Summit on Happiness," hosted by Emory University's Center for the Study of Law and Religion, many of the world's religions have nothing against humans seeking to be happy.

Can I really ditch the guilt and go for the gusto?

According to spiritual leaders from the Christian, Muslim, Jewish and Buddhist traditions, the answer is yes -- with a few conditions.

His Holiness the XIV Dalai Lama, the star of the show, has said that the very purpose of life is to be happy, so long as "one person or group does not seek happiness or glory at the expense of others." He didn't disappoint at the summit, sticking up for happiness as well as world peace at every opportunity, and laughing or chuckling fairly consistently throughout the event.

The Dalai Lama was joined on the panel by Rev. Katharine Jefferts Schori, presiding bishop of the Episcopal Church, Chief Rabbi Lord Jonathan Sacks of the United Hebrew Congregations of the Commonwealth and Islamic scholar Professor Seyyed Hossein Nasr of George Washington University.

They agreed wholeheartedly that faithfulness and happiness were not mutually exclusive.

Click here to read the top 10 things she learned about spiritual happiness.

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Brain trumps hand in Stone Age tool study

By Carol Clark

Was it the evolution of the hand, or of the brain, that enabled prehistoric toolmakers to make the leap from simple flakes of rock to a sophisticated hand axe?

A new study finds that the ability to plan complex tasks was key. The research, published today in the Public Library of Science journal PLoS ONE, is the first to use a cyber data glove to precisely measure the hand movements of stone tool making, and compare the results to brain activation.

“Making a hand axe appears to require higher-order cognition in a part of the brain commonly known as Broca’s area,” said Emory anthropologist Dietrich Stout, co-author of the study. It’s an area associated with hierarchical planning and language processing, he noted, further suggesting links between tool-making and language evolution.

“The leap from stone flakes to intentionally shaped hand axes has been seen as a watershed in human prehistory, providing our first evidence for the imposition of preconceived, human designs on the natural world,” he said.
"For the past two million years, stone tool making has been the most common and consistent human technology," Stout says. Photo by Carol Clark.

Stout is an experimental archeologist who recreates prehistoric tool making to study the evolution of the human brain and mind. Subjects actually knap tools from stone as activity in their brains is recorded. (Watch the video, above, to see how Stone Age tools were made.)

“Changes in the hand and grip were probably what made it possible to make the first stone tools,” Stout said. “Increasingly we’re finding that the earliest tools required visual and motor skills, but were conceptually simple.”

For this study, Stout used a data glove to record the exact hand postures of the research subject across a range of prehistoric technologies. He teamed with Aldo Faisal, a neuroscientist at Imperial College London, and archeologists Jan Apel of Gotland University College in Sweden and Bruce Bradley of Exeter University in Devon, England.

The researchers compared the manual dexterity for the tasks involved in making two types of tools: Oldowan flakes and Late Acheulean hand axes. Simple Oldowan stone flakes are the earliest known tools, dating back 2.6 million years. The Late Acheulean hand axe, going back 500,000 years, embodies a higher level of refinement and standardization.

“I assumed that the manual dexterity was going to be greater for making the hand axe,” Stout said. “But we found that the hand gestures were so similar that we couldn’t distinguish them.”
The leap from stone flakes to a hand axe was "a watershed in human prehistory," Stout says. Photo by Carol Clark.

A previous study by Stout found differences in the brain activation associated with Oldowan versus Acheulean technologies. It was unclear, however, whether the difference was due to higher-level behavior organization or lower-level differences in manipulative complexity.

The results of the data glove study point to higher cognition. “The advances of Late Acheulean technology were not about increased dexterity. They were about the ability to plan complex action sequences,” Stout said.

A hand axe requires the maker to begin with a precise, symmetrical end in mind. A variety of tools are involved, from a large rock to rough out the basic shape of the axe, to a softer implement, such as an antler billet, to thin and sharpen the edges.

The ongoing research could lead to new understanding of the modern human brain. “For the past two million years, stone tool-making has been the most common and consistent human technology, done by virtually every society,” Stout said. "It’s an important human behavior that probably helped shape our brains.”

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Tracing our origins to the stars

The color mosaic of the Orion Nebula and nearby star-forming region. Credit: NASA, ESA, M. Robberto (Space telescope Science Institute) and the Hubble Space Telescope Orion Treasury Project Team.

Discover Magazine writes about how scientists are searching for the origins of life in deep space by teasing out different strands of the story of prebiotic chemistry:

Carbon, hydrogen, oxygen and other atoms knock about in nebulas, sometimes freely and sometimes bound up with ice and dust. They arrange themselves into elaborate molecular structures. Meteorites abound with organic compounds, which rain down on any nearby planets.

Helping to weave all those strands into a single, elegant narrative is an Emory University astrochemist with a providential name: Susanna Widicus Weaver. Through a series of models and experiments, she has demonstrated that ultraviolet radiation can break chemical bonds and split molecules into highly reactive fragments called radicals. It is difficult for radicals to do much at -440 degrees F, but when the temperature warms even slightly (as when a star begins to form), the radicals merge to form larger molecules …. In a major 2008 paper, Weaver predicted an abundance of such radicals in dust clouds. A thorough search of interstellar ice grains by infrared astronomers should determine whether radicals indeed play a primary role in constructing prebiotic molecules. …

We know that meteorites contain amino acids and even nucleobases, but not whether they scooped up those molecules from dust clouds or created them later, on their interplanetary course. “We really don’t know where the chemistry in the dust cloud stops and where the chemistry in meteorites starts up,” Weaver says. She notes that the answer has tremendous implications for one of science’s most fundamental questions: How common is life throughout the universe?

Read the full article in Discover.

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