Scientific American - December 2010

Anxiety

Psychedelic Cures Dinosaurs

Blood from Stone

Physics

December 2010 ScientificAmerican.com

Gas from Garbage

Robot ts Power Plan

The Universe’s Hidden Geometry

ving Better Li h throug Gaming

Nanotech Water Filters The DNAr Transisto

© 2010 Scientific American

HOW A PLAN TO HELP A RENEWABLE ENERGY COMPANY GROW

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on the cover This year’s edition of World Changing Ideas explores the leading ways that technology and innovation can create a healthier, cleaner, smarter world, from bio­log­ ically inspired algorithms to vegetarian robots to a cheap nanotech-based water filter. Photograph by Mark Hooper.

December 2010 Volume 303, Number 6

62

feature s

decades to achieve on a therapist’s couch. By Ro­land R. Griffiths and Charles S. Grob

INNOVATION

42 World Changing Ideas A special report on thoughts, trends and technologies that have the power to change our lives. PHYSICS

54 A Geometric Theory of Everything Deep down, the particles and forces of the universe are a manifestation of exquisite geometry. By A. Garrett Lisi and James Owen Weatherall PALEONTOLOGY

62 Blood from Stone Mounting evidence from dinosaur bones (such as “Big Mike’s,” shown above) shows that, contrary to common belief, soft tissue can survive in fossils for millions of years. By Mary H. Schweitzer BIOLOGY

70 Life Unseen The biological world reveals microscopic landscapes of surprising beauty. By Davide Castelvecchi

INFORMATION SCIENCE

80 Long Live the Web In an exclusive essay, the Web’s inventor argues that protecting the Web is critical not merely to the digital revolution but to our continued prosperity—and even our liberty. By Tim Berners-Lee LIFE SCIENCE

86 Jane of the Jungle Primatologist Jane Goodall shares insights from her 50 years among the chimpanzees of Gombe.  Interview by Kate Wong SPACE EXPLOR ATION

88 Jump-Starting the Orbital Economy For the first time in five decades, NASA will soon be out of the astronaut-launching business. The only way to save manned spaceflight may be to outsource it to private companies. By David H. Freedman ROBOTICS

94 Cyborg Beetles

HEALTH

76 Hallucinogens as Medicine In a matter of hours, mind-altering substances may induce the profound psychological realignments that can take

Tiny flying robots that are part machine and part insect may one day save lives in wars and disasters. By Michel M. Maharbiz and Hirotaka Sato

4  Scientific American, December 2010

Photograph by David Liittschwager

© 2010 Scientific American

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Producing TV programs to improve children’s health

thinking. The five winners all have a healthy dissatisfaction with the status quo and an infinite capacity to reinvent the world. These five outstanding Laureates each receive $50,000 to implement and expand their projects. And invent a better future for all of us in the process. Nnaemeka Ikegwuonu – Nigeria Developing interactive radio to promote sustainable farming

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Piyush Tewari – India Training volunteers to provide rapid care to road accident victims

Reese Fernandez – Philippines Enabling impoverished women to create eco-ethical fashion goods

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Department s

10 From the Editor 12 Letters 16 Science Agenda The laws of physics are the least of NASA’s challenges. By the Editors 16

18 Forum Truth, witnesses and brain scans. By Hank Greely

20 Advances Exoplanetary life. Malaria genetics. Beer foam math. Proving Hawking right. Wireless body armor. Science books and toys for kids. Jellyfish propulsion.

36 The Science of Health Do exercising and quitting smoking delay the onset of dementia? By Christine Gorman

40 TechnoFiles Speech-recognition software has quietly grown tendrils into every corner of our lives. By David Pogue

100 Recommended Eye-catching books for holiday gift-giving. By Kate Wong 18

102 Skeptic The difference between true and false conspiracy theories. By Michael Shermer

104 Anti Gravity A mind is a terrible thing to your waist. By Steve Mirsky

106 50, 100 & 150 Years Ago 108 Graphic Science Smart controls can rebuild collapsed fisheries.  By Mark Fischetti on the web

Tour Seven Amazing Exoplanets

Scientific American (ISSN 0036-8733), Volume 303, Number 6, December 2010 published monthly by Scientific American, a trading name of Nature America, Inc., 75 Varick Street, 9th Floor, New York, N.Y. 10013-1917. Periodicals postage paid at New York, N.Y., and at additional mailing offices. Canada Post International Publications Mail (Canadian Distribution) Sales Agreement No. 40012504. Canadian BN No. 127387652RT; QST No. Q1015332537. Publication Mail Agreement #40012504. Return undeliverable mail to Scientific American, P.O. Box 819, Stn Main, Markham, ON L3P 8A2. Individual Subscription rates: 1 year $39.97 (USD), Canada $49.97 (USD), International $61 (USD). Institutional Subscription rates: Schools and Public Libraries: 1 year $69 (USD), Canada $74 (USD), International $81 (USD). Businesses and Colleges/Universities: 1 year $299 (USD), Canada $304 (USD), International $311 (USD). Postmaster: Send address changes to Scientific American, Box 3187, Harlan, Iowa 51537. Reprints available: write Reprint Department, Scientific American, 75 Varick Street, 9th Floor, New York, N.Y. 10013-1917; fax: 646-563-7138; [email protected]. Subscription inquiries: U.S. and Canada (800) 333-1199; other (515) 248-7684. Send e-mail to [email protected]. Printed in U.S.A. Copyright © 2010 by Scientific American, a division of Nature America, Inc. All rights reserved.

8  Scientific American, December 2010

© 2010 Scientific American

Courtesy of NASA (rocket)

104

Astronomers are turning up exoplanets in droves, but what do these distant worlds look like? Hugo Award–winning artist Ron Miller interprets the data to give us a glimpse. Go to www.ScientificAmerican.com/dec2010

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From the Editor Mariette DiChristina is editor in chief of Scientific American.

Science That Matters

“I

s what you’re doing going to use of biological models. Turn to page 42. change the world?” asked LarWhile I’m writing, I’d like to propose ry Page, Google’s co-founder. two more potential world changers. First, “If not, maybe you should do what if we stopped feeling frozen by unsomething else.” certainties associated with climate change I was at the annual Sci Foo Camp host- and—at least for starters—simply began aped by Nature Publishing Group (Scientific plying good resources management withAmerican’s parent), the O’Reilly Media in existing human experience? Water manGroup and Google on its Mountain View, Calif., campus. At this “unconference,” attendees—scien­ tists and those with connections to science—created sessions on the spot, making for an energizing and free­wheeling exchange over a weekend. But I have found myself reflecting most often on Page’s words since. Scientific American itself regularly features advances that can shape our future for the better, Fun with science: Seventh graders got a sampling and we focus on a select list in at a U.S. Science & Engineering Festival event. the cover story, our second annual “World Changing Ideas.” Among the 10 agers have to plan anyway for year-to-year innovations are veggie-eating robots that variations—the 10-year flood, the 100-year produce electricity, a DNA transistor and drought, and so on—and it is not insurbioinspired algorithms. In fact, threading mountable to factor in additional adaptthrough the section are two themes: man- ability when making infrastructure adjustaging information and benefiting from the ments. I didn’t make that up: I learned that

lesson while moderating a panel of expert water managers during an all-day symposium on “The Climate Challenge” held by the Earth Institute’s Columbia Climate Center and the Danish Consulate General. (Watch the panel video at www.earth. columbia.edu/videos/watch/260.) And here’s another way to improve at least our corner of the world: What if U.S. culture finally started admiring and participating in science as an engine of our modern prosperity, instead of holding it on a pedestal apart? Scientific American recently served as a sponsor for the first national U.S. Science & Engineering Festival in Washington, D.C., and we’ve been media partners with the World Science Festival in New York City and others in the past. What if parents took kids to such festivals and museums as often as they went to ballgames or concerts? Maybe ultimately we could stop bemoaning the drop in science and math scores by U.S. students and our loss in global competitiveness, because we’d all appreciate those topics as much as we do fine literature, art and the latest action movie. I’d like to see us, in the near future, facing our problems by saying: “We’ll have to science that.” 

board of advisers President, Wenner-Gren Foundation for Anthropological Research

Roger Bingham

Co-Founder and Director, The Science Network

G. Steven Burrill

CEO, Burrill & Company

Arthur Caplan

Emanuel and Robert Hart Professor of Bioethics, University of Pennsylvania

George M. Church

Director, Center for Computational Genetics, Harvard Medical School

Rita Colwell

Distinguished Professor, University of Maryland College Park and Johns Hopkins Bloomberg School of Public Health

Drew Endy

Professor of Bioengineering, Stanford University

Ed Felten

Director, Center for Information Technology Policy, Princeton University

Michael S. Gazzaniga

Director, Sage Center for the Study of Mind, University of California, Santa Barbara

David Gross

Frederick W. Gluck Professor of Theoretical Physics, University of California, Santa Barbara (Nobel Prize in Physics, 2004)

Lene Vestergaard Hau

Mallinckrodt Professor of Physics and of Applied Physics, Harvard University

Danny Hillis

Co-chairman, Applied Minds

Daniel M. Kammen

Director, Renewable and Appropriate Energy Laboratory, University of California, Berkeley

Vinod Khosla

Founder, Khosla Ventures

Christof Koch

Lois and Victor Troendle Professor of Cognitive and Behavioral Biology, California Institute of Technology

Lawrence M. Krauss

Director, Origins Initiative, Arizona State University

Morten L. Kringelbach

Director, Hedonia: TrygFonden Research Group, University of Oxford and University of Aarhus

Steven Kyle

Professor of Applied Economics and Management, Cornell University

Robert S. Langer

David H. Koch Institute Professor, Massachusetts Institute of Technology

Lawrence Lessig

Professor, Harvard Law School

Ernest J. Moniz

Cecil and Ida Green Distinguished Professor, Massachusetts Institute of Technology

John P. Moore

Professor of Microbiology and Immunology, Weill Medical College of Cornell University

M. Granger Morgan

Professor and Head of Engineering and Public Policy, Carnegie Mellon University

Miguel Nicolelis

Co-director, Center for Neuroengineering, Duke University

Martin Nowak

Director, Program for Evolutionary Dynamics, Harvard University

Robert Palazzo

Provost and Professor of Biology, Rensselaer Polytechnic Institute

10  Scientific American, December 2010

Carolyn Porco

Leader, Cassini Imaging Science Team, and Director, CICLOPS, Space Science Institute

Vilayanur S. Ramachandran Director, Center for Brain and Cognition, University of California, San Diego

Lisa Randall

Professor of Physics, Harvard University

Martin Rees

Professor of Cosmology and Astrophysics, University of Cambridge

John Reganold

Regents Professor of Soil Science, Washington State University

Jeffrey D. Sachs

Director, The Earth Institute, Columbia University

Eugenie Scott

Executive Director, National Center for Science Education

Terry Sejnowski

Professor and Laboratory Head of Computational Neurobiology Laboratory, Salk Institute for Biological Studies

Michael Shermer

Publisher, Skeptic magazine

Michael Snyder

Professor of Genetics, Stanford University School of Medicine

Michael E. Webber

Associate Director, Center for International Energy & Environmental Policy, University of Texas at Austin

Steven Weinberg

Director, Theory Research Group, Department of Physics, University of Texas at Austin (Nobel Prize in Physics, 1979)

George M. Whitesides

Professor of Chemistry and Chemical Biology, Harvard University

Nathan Wolfe

Director, Global Viral Forecasting Initiative

R. James Woolsey, Jr.

Venture Partner, VantagePoint Venture Partners

Anton Zeilinger

Professor of Quantum Optics, Quantum Nanophysics, Quantum Information, University of Vienna

Jonathan Zittrain

Professor, Harvard Law School

Illustration by Nick Higgins

© 2010 Scientific American

Courtesy of colellaphoto.com

Leslie C. Aiello

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Letters [email protected]

“When whistle­ blowers speak truth to power, they could finally hold employers accountable.” RICHARD R. RENNER NATIONAL WHISTLEBLOWERS CENTER

August 2010 Blowing the Whistle In “Danger in School Labs” [News Scan], Beryl Lieff Benderly lists four fatalities from lab accidents. She notes that the Protecting America’s Workers Act would expand the jurisdiction of the Occupational Safety and Health Act of 1970 to include state employees, in particular those of state colleges and universities. Whistleblower protections would also improve. Sadly, 5,000 Americans die every year from workplace hazards. Sadder still, although dead bodies usually get Congress to pass better protections, opposition from the U.S. Chamber of Commerce has mired the bill in committees. Under the 1970 act, whistleblowers can file a complaint with the Occupational Safety and Health Administration, but if OSHA decides not to take any further action in the case, the whistleblower has no further rights to any hearing or appeal. This dependence on OSHA has been devastating for the vast majority of workers who face retaliation after raising safety concerns. In certain facilities, such as nuclear power plants, strong whistleblower protections already give workers in environmentally sensitive jobs meaningful legal remedies when they face retaliation for raising safety and compliance concerns. The new act would establish similar protections for all the employees OSHA covers in both the public and private sectors. When whistleblowers speak truth to pow-

er, they could finally hold employers accountable when they choose to retaliate. Our legislators need to know that lives are more important than Chamber of Commerce opposition. Richard R. Renner Legal director National Whistleblowers Center Washington, D.C. Human Bottleneck In “When the Sea Saved Humanity,” Curtis W. Marean mentions that everyone alive today descended from a group of people from a single region who survived a cold, dry spell that went on between 195,000 and 123,000 years ago. But in the same issue, in Michael Shermer’s Skeptic column “Our Neandertal Brethren,” we learn that we are the descendants of a population of hominids that migrated into Europe some 400,000 years ago and another population from Africa that migrated between 80,000 and 50,000 years ago. How can one reconcile both theories? Lionel Lecoq Basel, Switzerland MAREAN REPLIES:  In my article I described how, between roughly 190,000 and 130,000 years ago, the modern human lineage (at that time restricted to Africa) was bottlenecked to a small breeding population, apparently during a strong glacial phase. When that glacial phase ameliorated at about 125,000 years ago, this small population expanded and spread throughout Africa. A subgroup of this expanding population eventually squeezed its way out of Africa into the Middle East, and from there those immigrants went on to Europe and East Asia. As Shermer describes, Neandertal genome studies suggest that when this intrepid group of modern humans dispersed

12  Scientific American, December 2010

© 2010 Scientific American

from Africa they encountered Neandertals in an intimate manner. The result was genetic leakage from the Neandertal line into the modern human genome, and this was carried throughout the non-African lineages and maintained, perhaps because it carried with it adaptive advantages. All modern humans descend from the small group that survived the bottleneck; however, in the case of people of European and Asian background, that lineage is not “pure,” because our ancestors interbred with Neandertals. The Nean­der­ tal results highlight how scientists’ strict definitions of fossil and living species do not always fit together well. Marean describes his and his colleagues’ investigation at Pinnacle Point, South Africa, and notes that the current vegetation of the region is highly diverse and includes a large number of species that are characterized by edible root tubers and bulbs, that is, geophytes. The vegetation in any area on earth is dynamic, not static. It changes as the climate changes and as other factors that we do not understand change. Why, knowing the dynamic nature of vegetation, would one expect an abundance of geophytes so long ago? Frank Reichenbacher Scottsdale, Ariz. MAREAN REPLIES: The presence of a geo­ phyte plant part is often associated with an adaptation to hot, dry summers and arid climates, and that is the case for most of the geophytes in the Cape region, because the heartland of the Cape is dominated by winter rainfall. The entire Cape, including the fynbos and the interior Karoo, are superrich in geophyte diversity. Using other proxies such as large mammal fauna, micromammals and spel­ eo­thems, we can confidently state that through­­out the past 200,000 years the climates of the Cape were favorable to geo­ phytes, even during maximum glacial conditions. In fact, the Cape was probably drier during glacials, and thus geophytes were even more favored than they are today. Science and Fiction Michael Shermer’s “Our Neandertal Brethren” [Skeptic] ends with, “Now that is a

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Letters

tale worthy of a romantic novel, brought to you by science.” I believe this is exactly the plot of Jean M. Auel’s 1980 novel Clan of the Cave Bear. Once again, science follows science fiction. Rick Rantilla Bluffton, S.C. Faith and Foolishness Thanks to Lawrence M. Krauss for writing “Faith and Foolishness” [Critical Mass] and thanks to the editors of Scientific American for publishing it. Many of us who agree wholeheartedly with what Krauss has to say are all too familiar with the wrath visited on nonbelievers by those who proclaim themselves believers in a religion of peace and love. Dianne Wood Halfway, Ore. Krauss should be advised that most Americans who would describe themselves as Christian do not literally believe the world was created in six days a mere 6,000 years ago. Nor do any of the major Christian religions require their members to believe such a literal interpretation of the story of the origin of the world found in the Old Testament. Krauss’s commentary seems more an attack on some religions than an attack on ignorance. Rick Stager Birchrunville, Pa. Errata Ronald Wallenfels, a historian at New York University, alerted us to a few inaccuracies in Brendan Borrell’s “The First Humvee” [Origins]: “The Standard of Ur was certainly not a container; it may have been the decorated sound box of a large lyre. And its dimensions (20 by 47 centimeters) make it considerably larger than any ordinary ‘shoe­box,’ unless of course, it held a pair of sandals belonging to Gilgamesh, the mythical semidivine king of Uruk. The animals drawing these wagons are not horses, which did not make their appearance in any significant numbers in the Near East until they arrived from Central Asia in the early second millennium B.C.; rather they are a type of wild ass. The ‘poor foot soldiers . . . squirming to avoid [the] horses’ hooves’ are in fact dead enemy soldiers depicted nude as was the contemporary artistic convention.”

letters to t h e editor ®

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14  Scientific American, December 2010

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Letters may be edited for length and clarity. We regret that we cannot answer each one. Post a comment on any article at ScientificAmerican.com/dec2010

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Science Agenda by the Editors Opinion and analysis from Scientific American’s Board of Editors

Defying Politics The laws of physics are the least of NASA’s challenges

Orbital: NASA may send astronauts aloft in commercially owned rockets like SpaceX’s Falcon 9, which was test-fired in March.

specifications of orbital launches and leave the details to private enterprise. It will be able to spread its eggs among many baskets rather than putting them in one. The plan thus fights the political pressures with the only force that might be more powerful: the profit motive. Space businesses have a strong incentive to buy equipment and hire people for their technical merit rather than because their congressional representative was able to bring home the bacon. That’s one reason why Obama’s plan met with so much opposition. Still, Congress ended up mostly going along with it—and that will help to let NASA be NASA. Bush’s plan failed for lack of follow-through, and if Obama’s is not to do the same, he must keep pushing for more reforms. The first goal should be to fix the flaws in the plan that Congress has enacted, beginning with the lack of sufficient funds for technology development. If NASA were more consistent about investing in new technology, future missions could pull what they need off the shelf and would have a fighting chance of staying on budget. More broadly, Congress must find a way to give NASA some stability of funding and purpose. The Augustine commission pointed out that NASA has been hobbled by “recurring budget ambiguities” and congressional micromanagement. The agency needs greater autonomy, perhaps even a dedicated funding stream. The specific plan—be it Bush’s, Obama’s or whoever’s—doesn’t matter. Where politicians have failed NASA is in not letting it do its job. Engineers will make mistakes, but engineers learn from their mistakes. It is time for politicians to do the same.  Comment on this article   www.ScientificAmerican.com/dec2010

16  Scientific American, December 2010

© 2010 Scientific American

Courtesy of Chris Thompson SpaceX

A crisis at NASA forces a new president to take action. A panel issues a report. The president gives a speech. He directs NASA to find a better way to get astronauts into orbit and to encourage private companies to enter the space taxi business. The plan promises to be the biggest shake-up of the space program since the glory days of the moon landings. Some embrace it; others take a dislike. So it was with President George W. Bush’s vision for NASA in 2004, which sought to rekindle the agency’s exploratory spirit after the space shuttle Columbia disaster. The plan, though, fell apart when Bush failed to come through with the money to implement it. And so President Barack Obama came into office, found NASA in dire straits, commissioned a panel, led by aerospace veteran Norman Augustine, to work the problem, and made a big speech in April. How will the story end this time? Only strong presidential follow-through can keep NASA on course. Obama proposed jettisoning much of the Constellation program, which Bush set up to build rockets and Apollo-like capsules to replace the space shuttle, and instead paying private companies such as Elon Musk’s SpaceX to launch astronauts into orbit. He also relaxed Bush’s deadlines to return to the moon, refocusing on what the Augustine commission called a “flexible path” of incrementally more difficult missions to asteroids and ultimately Mars [see “Jump-Starting the Orbital Economy,” by David H. Freedman, on page 88]. For supporters of Constellation, the proposal was a call to arms. Even the reclusive Neil Armstrong came out to question it, and over the summer Congress tore it apart. The Senate agreed to a stripped-down version; the House of Representatives rejected it altogether. As an end-of-September fiscal deadline loomed, the House caved in and went along with the Senate. Leaving aside the politics, the disagreement hinged on a genuine dilemma. Skeptics of the plan say that private companies are unproven. Proponents worry that keeping Constellation alive would be throwing good money after bad. Better to fund entrepreneurs who can drive down the cost of orbital launches. Both sides have a point, but what tilts the balance in favor of Obama’s plan is that we can’t really “leave aside the politics.” For Congress, NASA is not solely—or even primarily—a space agency. It is also a jobs agency, an industrial-policy agency and a foreign-policy agency. These ulterior motives keep getting in the way of good engineering. For instance, Obama had proposed undertaking basic technology development and only then deciding on the design for a new heavy-lift rocket, but the Senate insisted that NASA build the rocket with existing technology—which preserves jobs, even if it raises costs and hampers innovation in the long term. The charm of Obama’s plan is that it seeks to disentangle NASA from these vested interests. NASA will set the price and technical

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To Tell the Truth Brain scans should not be used for lie detection unless their reliability is proven Neuroscientists have been using brain scans to learn how to read minds. This research is increasing our basic understanding of the human brain and offering hope for medical breakthroughs. We should all applaud this work. Commercial firms, however, are beginning to apply this research to lie detection, selling their services. The technology is tempting, but before we accept it, we need to think hard about it—and go slow. The trouble is not with the pace of research. Neuroscientists have been publishing articles about detecting lies with functional magnetic resonance imaging (fMRI) for nearly 10 years. About 25 published studies have found correlations between when experimental subjects were telling a lie and the pattern of blood flow in their brains. The trouble is that different studies, using different methods, have drawn conclusions based on the activity of different brain regions. And all the studies so far have taken place in the artificial environment of the laboratory, using people who knew they were taking part in an experiment and who were following instructions to lie. None of the studies examined lie detection in real-world situations. No government agency has found that this method works; no independent bodies have tested the approach. Yet people are buying lie-detection

reports, wrapped in the glamour of science, to try to prove their honesty. In May two separate cases wound up in the courts. One case hinged on whether the technology works. In a federal district court in Tennessee, the defendant in a Medicare fraud case wanted to introduce an fMRI lie-detection report into evidence to prove that he had not intended to commit fraud. After more than 12 hours of expert testimony, the judge concluded that the evidence should not be admitted. He found, correctly, that the accuracy of the method was unknown in real-world settings, that there were no standards for how the method should be applied, and that the scientific community did not generally accept this application of the technology. The other case turned on the question of whether we should use the technology, even if it worked. The plaintiff in a state court civil case in Brooklyn, N.Y., wanted to introduce an fMRI report to show that her main witness was telling the truth. The judge in that case ruled that the credibility of a fact witness was solely a question for the jury; expert testimony about the witness’s credibility was inadmissible, whether or not it was reliable. These judges made good decisions, but tens of thousands of trial judges in America may have to rule on this technology, sometimes after hearing from good lawyers and expert witnesses and sometimes not. More important, millions of lives may be affected by the use of these lie-detection reports outside the courtroom—in criminal investigations, in business deals, perhaps in the military or the intelligence community, even in love and marriage. Before the technology gets a foothold in society, we must answer, more broadly, the questions these judges confronted. We should ban nonresearch use of neuroimaging for lie detection until the method has been proved effective by rigorous, independent, scientific testing. Otherwise we risk hurting people and tarnishing the good name of neuroscience. I don’t know if fMRI will ever pass that test. If it does, when and how would we use it? Would we force defendants to submit to it? What about suspects, terrorists, misbehaving students, unruly passengers in airport security lines, or teenage children? Lie detection isn’t the only mind-reading use of brain scans that the legal profession could use—scientists are working on detecting pain, biases and memories. We may ultimately decide to reject or accept these technologies. Either way, we must prepare for them.  Comment on this article   www.ScientificAmerican.com/dec2010

18  Scientific American, December 2010

© 2010 Scientific American

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Hank Greely is Deane F. and Kate Edelman Johnson Professor of Law and professor of genetics at Stanford University. He specializes in ethical, legal and social issues arising from advances in the biosciences.

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Understanding the Universe: An Introduction to Astronomy, 2nd Edition Taught by Professor Alex Filippenko, University of California, Berkeley Lecture Titles 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48.

A Grand Tour of the Cosmos The Rainbow Connection Sunrise, Sunset Bright Objects in the Night Sky Fainter Phenomena in the Night Sky Our Sky through Binoculars and Telescopes The Celestial Sphere The Reason for the Seasons Lunar Phases and Eerie Lunar Eclipses Glorious Total Solar Eclipses More Eclipse Tales Early Studies of the Solar System The Geocentric Universe Galileo and the Copernican Revolution Refinements to the Heliocentric Model On the Shoulders of Giants Surveying Space and Time Scale Models of the Universe Light—The Supreme Informant The Wave-Particle Duality of Light The Colors of Stars The Fingerprints of Atoms Modern Telescopes A Better Set of Eyes Our Sun, the Nearest Star The Earth, Third Rock from the Sun Our Moon, Earth’s Nearest Neighbor Mercury and Venus Of Mars and Martians Jupiter and Its Amazing Moons Magnificent Saturn Uranus and Neptune, the Small Giants Pluto and Its Cousins Asteroids and Dwarf Planets Comets—Gorgeous Primordial Snowballs Catastrophic Collisions The Formation of Planetary Systems The Quest for Other Planetary Systems Extra-Solar Planets Galore! Life Beyond the Earth The Search for Extraterrestrials Special Relativity and Interstellar Travel Stars—Distant Suns The Intrinsic Brightnesses of Stars The Diverse Sizes of Stars Binary Stars and Stellar Masses Star Clusters, Ages, and Remote Distances How Stars Shine—Nature’s Nuclear Reactors

49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70. 71. 72. 73. 74. 75. 76. 77. 78. 79. 80. 81. 82. 83. 84. 85. 86. 87. 88. 89. 90. 91. 92. 93. 94. 95. 96.

Solar Neutrinos—Probes of the Sun’s Core Brown Dwarfs and Free-Floating Planets Our Sun’s Brilliant Future White Dwarfs and Nova Eruptions Exploding Stars—Celestial Fireworks! White Dwarf Supernovae— Stealing to Explode Core-Collapse Supernovae—Gravity Wins The Brightest Supernova in Nearly 400 Years The Corpses of Massive Stars Einstein’s General Theory of Relativity Warping of Space and Time Black Holes—Abandon Hope, Ye Who Enter The Quest for Black Holes Imagining the Journey to a Black Hole Wormholes—Gateways to Other Universes? Quantum Physics and Black-Hole Evaporation Enigmatic Gamma-Ray Bursts Birth Cries of Black Holes Our Home—The Milky Way Galaxy Structure of the Milky Way Galaxy Other Galaxies—”Island Universes” The Dark Side of Matter Cosmology—The Really Big Picture Expansion of the Universe and the Big Bang Searching for Distant Galaxies The Evolution of Galaxies Active Galaxies and Quasars Cosmic Powerhouses of the Distant Past Supermassive Black Holes Feeding the Monster The Paradox of the Dark Night Sky The Age of the Universe When Geometry Is Destiny The Mass Density of the Universe Einstein’s Biggest Blunder? The Afterglow of the Big Bang Ripples in the Cosmic Background Radiation The Stuff of the Cosmos Dark Energy—Quantum Fluctuations? Dark Energy—Quintessence? Grand Unification & Theories of Everything Searching for Hidden Dimensions The Shape, Size, and Fate of the Universe In the Beginning The Inflationary Universe The Ultimate Free Lunch? A Universe of Universes Reflections on Life and the Cosmos

10/22/10 4:15:55 PM

Advances Top developments in science, technology and medicine

A day in the life: An artist’s rendering of Gliese 581g.

Black Plants and Twilight Zones Discoveries of distant planets are challenging theorists to think deeply about extraterrestrial life Astronomers have long searched for a planet that could harbor life outside our solar system. When reports came in earlier this fall of the not too hot, not too cold exoplanet Gliese 581g, it was like the answer to a dream. “If it’s confirmed, I think it’s definitely the planet we’ve been waiting for, for a long time,” says Rory Barnes, an astrobiologist at the University of Washington who wasn’t involved in the research. The wait may continue for a while. Soon after University of California, Santa Cruz, astronomer Steven Vogt and his collaborators reported the “Goldilocks” exoplanet, a rival Swiss group said it could not find evidence for Gliese 581g in its own data set. Confirming the new find, based on 11 years of subtle and indirect telescope-based measurements, could require several more years. The tantalizing data, though, have already galvanized astronomers to step up their research on the conditions necessary for extraterrestrial life. The possibility that Gliese 581g may exist, they say, has added a new urgency for more sophisticated supercomputer models of life on other Earth-size planets. Scientists, theoretical astrophysicists among them, combine

astronomical observations with what they know about life on Earth to build simulations of exoplanet environments. Amid a recent surge of detected planets, realistic models could provide critical guidance for future missions seeking out signs of life in the universe. Recently Gliese 581g has become a focal point for this research. Its nearly circular orbit around a red dwarf star would position it at the optimal distance for temperatures permitting liquid water on the surface—an essential feature for life. The red dwarf, though, emits only 1 percent of the light from our sun. Photosynthetic organisms on the planet would likely absorb as much of the weaker starlight as possible, making them appear black, according to modeling by Nancy Kiang of the NASA Goddard Institute for Space Studies in New York City and collaborators at the University of Washington–based Virtual Planetary Laboratory. Preliminary calculations also support the idea that one side of Gliese 581g always faces its star and roasts in temperatures up to 64 degrees Celsius, whereas the planet’s dark side sees relentless North Pole–like winters. This positioning, still a matter of debate, might leave a more livable zone awash in a “perpetual sunset,” as Vogt calls it. If such a hypothesis proves correct, Kiang says the specific wavelengths of light reaching each longitude could even prompt a rainbowlike gradient of plant colors with pigments adapted to absorb the light streaming across the surface. Beyond energizing theorists, Gliese 581g has whet astronomers’ appetites for what many expect to be hundreds of similar discoveries outside our solar system. “Either we’ve been very lucky and we won’t find another one again for a long time,” Vogt says, “or there’s a lot of them out there.” —Bryn Nelson

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20  Scientific American, December 2010

© 2010 Scientific American

Ron Miller

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© 2010 Scientific American

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The Incredible, Incredible, The Edible Foam Foam Edible If you you sometimes sometimes start start your morning with with aa If your morning frothy cappuccino and finish off the evening �߸î�ā`DÇÇø``�³¸D³l�³�ä�¸�î�xxþx³�³� with D a �xDlā heady �§Dää glass ¸� of Uxxßj beer, î�x³ then ā¸øß your lDā day ÿ�î� opens and closes with one of the most scien¸Çx³äD³l`§¸äxäÿ�î�¸³x¸�î�x­¸äîä`�x³tifically �³îß��ø�³� intriguing ¦�³lä kinds ¸� of �¸¸li food: î�x the xl�U§x edible î��`D§§ā foam. There are deep mathematical myster�¸D­Í5�xßxDßxlxxÇ­Dî�x­Dî�`D§­āäîxßies in these interlocked bubbles, and recently �xä�³î�xäx�³îxߧ¸`¦xlUøUU§xäjD³lßx`x³î§ā they have also become one of the most fertile î�xā�DþxD§ä¸Ux`¸­x¸³x¸�î�x­¸äî�xßî�§x areas for culinary innovation. DßxDä�¸ß`ø§�³Dßā�³³¸þDî�¸³Í Top-ranked `�x� chef xßßD³ Ferran lß�K Adrià ¸� of x§ ø§§� elBulli 5¸Ç�ßD³¦xl in DîD§¸³�Dj Catalonia, 3ÇD�³j Spain, Ux�D³ began xĀÇxß�­x³î�³� experimenting �³ with `ø§�³Dßā culinary �¸D­ä foams �³ in î�x the ­�l�¿´´ćä mid-1990s �³ in ��ä his ÿ�î� quest to present diners Ôøxäîî¸Çßxäx³îl�³xßä with ³xÿ new D³l and ø³xĀunexÿ�î� pected culinary experiÇx`îxl`ø§�³DßāxĀÇxß�ences. lß�K Adrià øäxl used ø³unx³`xäÍ conventional �¸D­�³� foaming `¸³þx³î�¸³D§ agents äø`� such Dä as �x§Dî�³ gelatin D�x³îä or §x`�î��³ lecithin ßDî�xß rather î�D³ than ¸ß eggs or cream. He used x��ä¸ß`ßxD­Íxøäxl whipping siphons pow­ ÿ��ÇÇ�³�ä�Ç�¸³äǸÿ� ered by pressurized nixßxlUāÇßxääøß�ąxl³�trous oxide—much like î߸øä¸Ā�lx­ø`�§�¦x cans ¸� of 2xll��ÿ�Ç Reddi-wip Uøî but `D³ä sturdier—to create eth­ äîøßl�xßî¸`ßxDîxxî�� er­xD§�¸D­ä�߸­�¸¸lä eal foams from foods xß as l�þxßäx diverse Dä as `¸lj cod, �¸�x foie Dä gras, ­øä�߸¸­ä mushrooms D³l and �ßDäj potatoes. 5�Dî That äîDßîxl started ǸîDî¸xäÍ a ßxþ¸§øî�¸³ revolution �³ in �¸D­äj foams, D as `�x�äj chefs, D­¸³� among î�x­ them Dä Hes­î¸³ ton §ø­x³î�D§ Blumenthal ¸� of ßDāj Bray, ³�§D³lj England, %xÿ New xä York �îāÜä City’s =ā§�x Wylie ø�ßxä³xj Dufresne, D³l and ��`D�¸Üä Chicago’s ?¸ß¦ Grant Achatz, have taken to foaming all manßD³î `�Dîąj�DþxîD¦x³î¸�¸D­�³�D§§­D³ner of savory foods. ³x߸�äDþ¸ßā�¸¸läÍ These l�ä�xä dishes �Dþx have D³ an DøßD aura ¸� of ­āäî�Ôøx mystique 5�xäx about them and not just for their novel texDU¸øîî�x­D³l³¸î¥øäî�¸ßî�x�ß³¸þx§îxĀture. Although �¸D­ä foams ­Dā may §¸¸¦ look §�¦x like ßD³l¸­ random îøßxÍ §î�¸ø�� jumbles, the bubbles within all foams seem to ¥ø­U§xäjî�xUøUU§xäÿ�î��³D§§�¸D­ääxx­î¸ self-organize î¸ to ¸Uxā obey î�ßxx three ø³�þxßäD§ universal ßø§xä rules äx§��¸ß�D³�ąx first observed by Belgian physicist Joseph Pla�ßäî¸UäxßþxlUā x§��D³Ç�āä�`�äî ¸äxÇ�0§Dteau �³ in ¿}èðÍ 1873. 5�xäx These ßø§xä rules Dßx are ä�­Ç§x simple î¸ to lxdeîxDø scribe but have been remarkably hard to exä`ß�UxUøî�DþxUxx³ßx­DߦDU§ā�Dßlî¸xĀplain. The first rule is that whenever bubbles ǧD�³Í5�x�ßäîßø§x�äî�Dîÿ�x³xþxßUøUU§xä join, î�ßxx three �§­ film äøß�D`xä surfaces �³îxßäx`î intersect Dî at xþxßā every ¥¸�³j edge. %¸î Not îÿ¸ç two; ³xþxß never �¸øßD§ÿDāä four—always î�ßxxÍ three. xl�xÍ Second, each pair of intersecting films, once 3x`¸³ljxD`�ÇD�߸��³îxßäx`î�³��§­äj¸³`x they have stabilized, forms an angle of exactly î�xā�DþxäîDU�§�ąxlj�¸ß­äD³D³�§x¸�xĀD`î§ā

22  Scientific American, December 2010

© 2010 Scientific American

120 degrees. Finally, wherever edges meet at ¿öćlx�ßxxäÍ�³D§§ājÿ�xßxþxßxl�xä­xxîDî a Ǹ�³îj point, î�x the xl�xä edges D§ÿDāä always ³ø­Uxß number xĀD`î§ā exactly D four, and the angle is always the inverse co�¸øßjD³lî�xD³�§x�äD§ÿDāäî�x�³þxßäx`¸(about 109.5 degrees). sine of –11//33ÉDU¸øî¿ć´Í�lx�ßxxäÊÍ ä�³x¸�� Only a century later, in 1976, did Rutgers '³§āD`x³îøßā§Dîxßj�³¿´èéjl�l2øî�xßä University mathematician Jean Taylor prove 7³�þxßä�îā­Dî�x­Dî�`�D³ xD³5Dā§¸ßÇ߸þx that, at least in the case of two joined bubî�DîjDî§xDäî�³î�x`Däx¸�îÿ¸¥¸�³xlUøUbles, Plateau’s rules derive from the action of U§xäj0§DîxDøÜäßø§xälxß�þx�߸­î�xD`î�¸³¸� surface tension, which forces the bubbles to äøß�D`xîx³ä�¸³jÿ��`��¸ß`xäî�xUøUU§xäî¸ adopt the most stable configuration. MatheDl¸Çîî�x­¸äîäîDU§x`¸³��øßDî�¸³Í$Dî�xmaticians Dßx are äî�§§ still Dîîx­Çî�³� attempting î¸ to ³D�§ nail l¸ÿ³ down ­Dî�`�D³ä exactly what happens in a froth of three or xĀD`î§āÿ�Dî�DÇÇx³ä�³D�߸î�¸�î�ßxx¸ß more bubbles, as well ­¸ßxUøUU§xäjDäÿx§§ as the unsolved quesDäî�xø³ä¸§þxlÔøxätion ¸� of ÿ�Dî what DßßD³�xarrangeî�¸³ ment of bubble shapes ­x³î¸�UøUU§xä�DÇxä in a foam will fill a con�³D�¸D­ÿ�§§�§§D`¸³tainer while using the îD�³xßÿ��§xøä�³�î�x least surface area (and §xDäîäøß�D`xDßxDÉD³l thus the least energy). î�øäî�x§xDäîx³xß�āÊÍ In 1887 Lord Kelvin had ³¿}}è"¸ßl!x§þ�³�Dl proposed î�Dî that D a �¸³honÇ߸Ǹäxl eycomb ¸� of îxîßD tetra­lx` dec­a� a­ xā`¸­U hedrons, xD`� each ÿ�î� with ä�Ā six �xl߸³äj square D³l and x���î eight �xĀhexäÔøDßx agonal faces, is the anD�¸³D§�D`xäj�äî�xD³swer. But in 1994 phys­i� i­ äÿxßÍ øî�³¿´´�Ç�āä cists Dennis Weaire and `�äîäx³³�ä=xD�ßxD³l Robert Phel­D³¸�5ß�³�îā an of Trinity 2¸Uxßî0�x§ College in Dublin pub¸§§x�x�³øU§�³ÇøUlished an even better— §�ä�xlD³xþx³Uxîîxß though ³¸î not ³x`xä neces­äDß sar­�§ā ily ¸Çî�­D§丧øî�¸³i optimal—solution: D a î�¸ø�� foam ¸� of îÿ¸ two ¦�³lä kinds ¸� of `x§§äj cells, ¸³x one ­Dlx made 丧x§ā solely �¸D­ from 12 pentagons and the other constructed �߸­¿öÇx³îD�¸³äD³lî�x¸î�xß`¸³äîßø`îxl from two hexagons and 10 pentagons. �߸­îÿ¸�xĀD�¸³äD³l¿ćÇx³îD�¸³äÍ In foamy foods, bubbles that do not fol³�¸D­ā�¸¸läjUøUU§xäî�Dîl¸³¸î�¸§low 0§DîxDøÜä Plateau’s ßø§xä rules Ôø�`¦§ā quickly ǸÇÍ pop. 5�x The äD­x same §¸ÿ fate occurs to bubbles that are too small: sur�Dîx¸``øßäî¸UøUU§xäî�DîDßxä­D§§iäøßface tension raises the pressure inside them �D`xîx³ä�¸³ßD�äxäî�xÇßxääøßx�³ä�lxî�x­ beyond the breaking point. That is one reaUxā¸³lî�xUßxD¦�³�Ǹ�³îÍ5�Dî�丳xßxDson that liquid foams become coarser as they 丳î�Dî§�Ôø�l�¸D­äUx`¸­x`¸DßäxßDäî�xā age—and why it is best to sip your cappucciD�xD³lÿ�ā�î�äUxäîî¸ä�Çā¸øß`DÇÇø``�no while it is fresh. ³¸ÿ��§x�î�ä�ßxä�Í  —W. Wayt Wayt Gibbs Gibbs and and Nathan Nathan Myhrvold Myhrvold —W. Myhrvold �ä is Døî�¸ß author D³l and �UUä Gibbs �ä is xl�î¸ß editor ¸� of $ā�ßþ¸§l Modernist Cuisine: Cuisine: The The Art Art and and Science Science of of CookCookModernist ing, ä`�xlø§xl�¸ßÇøU§�`Dî�¸³�³$Dß`�öć¿¿Í scheduled for publication in March 2011. ing,

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Advances P HYSICS

Hawking Was Right (Probably) In 1974 Stephen Hawking Hawking  '&*+,#+
postulated +that +
#"
&#*
*should &,#
!-
&7

+)!"#
&
black holes give off a trickle of ')+!#*
!)
&,+)
particles, &)
or )!+!&%
radiation, )&$
from +their outer &,%)!*
 
." boundaries. The
3%!%
*+#!* finding established Hawk­
!­i%*
)',++!&%
*

)!##!%+
*!%+!*+
%
ng’s reputation as a brilliant scientist and *+
+ !*
highly ! #0
-!*!#
',#!
set the
*+
&)
stage for his visible public ')&3#
!
!%#,*
profile, . which includes ')&-&+!-
provocative *+ best*##!%
selling &&"*
books %
and ,*+
guest '')%*
appearances &%
on

%
+ The Simpsons. In the
$!*+
&
##
+ midst of all the
 ce­ #)!+0
+ &)0
&
."!%
) lebrity, the
&)!!%#
+ original theory of Hawking ra­ !+!&%
*
+ &#
' %&$%&%
!*
diation, as the
#"
black hole phenomenon is "%&.%
*
#$&*+
%
&)&++%
+
#*+
known, has almost been forgotten, at least 0
+ by the
%)#
',#!
 general public. The
!%+
$!**!&%
faint emission *
%-)
%
++
)&$

)#
#"
has never been detected from a real black &#
%
)*) )*
have -
%&+
%
#
hole, and researchers not been able +&
')&,
+ to produce the
7+
!%
+ effect in the
#
lab.


.
0)*
&

)&,'
&
*!%+!*+*
!%
A few years ago a group of scientists in +#0
!
+&
+)0

%.
'')& Italy decided to try a new approach
+&
+*+
to test

."!%*
*!*
 0
,*
Hawking’s +thesis. They used 
a '!
piece &
of #**
glass +&
to ))+
re-create 
a #"
&#*
2-%+
&)!1&%56 black hole’s “event horizon”— +the
'&!%+
point &
of %&
no )+,)%
return 0&%
beyond . !
-%
#! which even light+
!*
+&&
*#&.
+&
is too slow to *'
. )
."
escape, where Hawk­!i%
#!-*
ng believes +the
)!+!&%
radiation .&,#
would )!*
arise.

#&%*!
&)!%)0
$++)
%
Alongside ordinary matter and #! &#
he
) light+
##!%
falling !%+&
into 
a #"
black hole, rea­ *&%
soned, &, ought+
+&
to 
be ')+!#*
particles '&''!%
popping !%
in %
&,+
&
/!*+%
,%+,$
$ %!*
and out of existence. Quantum mechanics !++*
+
*, &)+#!-
')+!#
dictates +that such
*short-lived particle '!)*
)!*
-%
)&$
$'+0
*'
!%
$&*+
pairs arise even from empty space; in most &)%)*
&
+ &*
'!)*
(,!"#0
corners of the
&*$&*
+ cosmos, those pairs quickly !*'')
+&+ )
"
!%+&
+ disappear together back into the
-,,$
vacuum. ,+
+
%
-%+
&)!1&%
&%
')+!#
$0
But at an event horizon, one particle may 
'+,)
0
+ &#
#-!%
+ be captured by the
#"
black hole, leaving the
&+ )
)
+&
*'
*
)!+!&% other free to escape as radiation.

24  Scientific

!%+!3
$)!%
$)
 American, December 2010

© 2010 Scientific American

%!#
!&
&
+ Daniele Faccio of the
%!-)*!+0
&
% University of In­ *,)!
%
!*
&##,*
)+
+ subria and his colleagues created the
-%+
event &)!1&%
!%

*+!&%
&
,*
*!#!
#**

horizon in a section of fused silica glass, a $!,$
!%
. !
!%+%*
#*)
',#**
%
medium in which intense laser pulses can #&##0
perturb ')+,)
the + 
speed *'
at +
which . !
light #! +
locally '***
through + )&,
the + 
glass. #**
That  +
perturba­ ')+,) passes +!&%
&)$*

$&-!%
-%+
&)!1&%
#&" tion forms a moving event horizon, block­ !%
' &+&%*
)&$
&-)
"!%
!+


'!)
&
ing photons from over­t+aking it. If a pair of ' &+&%*
!*
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photons is produced close enough
+&
+ to that -%+
horizon, &)!1&%
+they 0
.!##
&$
*')+ event will become separat­ 
%
.!##

,%#
+&
)+,)%
+&
+ ed and will be unable to return to the
-,,$
The  
researchers )*) )*
recorded )&)
vacuum. ' &+&%*
*+)"!%
&,+.)
)&$
+ photons streaking outward from the
#**
&,+
&%
' &+&%
')

#*)
glass, about one photon per 100 laser ',#**
with .!+
all ##
the + 
traits +)!+*
they + 0
had 
pulses, ')!+
for &)
Hawking ."!%
radiation. )!+!&%
predicted  0
)%+#0
',#!* 
+their !)
)*,#+*
They recently published results !%
  
  
   in Physical Review Letters.  0*!!*+*
!*)
Physicists disagree &,+
about /+#0
exactly . +
+the
&*)-+!&%
$%*
#
 what observation means. Ulf Le­ &% )+
of &
the + 
University %!-)*!+0
of &
St. +
An­

% onhardt ).*
in !%
Scotland &+#%
says *0*
the + 
new %.
re­ ) drews *)
!%
)')*%+*
+ search indeed represents the
3)*+
& first ob­ *)-+!&%
&
."!%
)!+!&%
+ )*
servation of Hawking radiation. Others )
%&+
*
*,)
 &&)

&*&%
are not as sure. Theodore A. Jacobson &
+the
%!-)*!+0
&
)0#%
*0*
of University of Maryland says he
!*
$&)
&%-!%
0
%&+ )
)&,'*
is more convinced by another group’s )%+
paper '')
on &%
a
nonquantum %&%(,%+,$
ana­ % recent #&,
&
."!%
)!+!&%
!%
4&.!%
logue of Hawking radiation in flowing .+)
He 
points '&!%+*
out &,+
that + +
Faccio’s

!&*
water. )&,'
cannot %%&+
verify -)!0
that + +
photons ' &+&%*
ap­ ' group ')
!%
'!)*
+
+ &)!1&%
2%
pear in pairs at the
-%+
event horizon. “In &,)
!
'!
&
#**
.
-
%&
.0
our big piece of glass we have no way &
*0!%
. )
+the
&+ )
' &+&%
.!##
of saying where other photon will %
,'5
!&
%&+*
,+
&% )+
end up,” Faccio notes. But Leonhardt, . &
')&'&*
+ &)! who proposed the
)+!3!#
-%+
artificial event hori­ 1&%
scheme * $
and %
is !*
investigating !%-*+!+!%
the + 
zon ' %&$%&%
in !%
optical &'+!#
fibers, 3)*
could &,#
phenomenon ++
both &+
photons ' &+&%*
and %
show * &.
their + !)
detect &$$&%
&)!!%
2%
+

common origin. “Once he
&*
+ does that, I + !%"
!+
.!##
#&*
##
+ think it will close all the
!*,**!&%*5
discussions,”

!&
*0*
 
 
Faccio says. —John Matson

Matt ZANG MATT Zang

Researchers may have re-created an elusive black hole phenomenon in the lab

Pat  e n t 
wat  c h  PAT PATEENT NT NO. NO. 7,805,767 7,805,767

u.s. PATENT Patent AND and TRADEMARK trademark OFFICE office U.S.

Body BODY Armor ARMOR with WITH BATTERIES BATTERIES You’d ugging around You’d never never catch catch Iron Iron Man Man llugging around seven seven kinds kinds of of batteries. batteries. But But that’s that’s exactly exactly what what U.S. U.S. Army Army squad squad leaders leaders are are required required to to do do on on 72-hour 72-hour missions. missions. The The batteries, batteries, which which can can weigh weigh aa total total of of 16 16 pounds, pounds, are are used used to to power power radios, radios, GPS GPS syssystems tems and and night-vision night-vision goggles. goggles. One One of of the the goals goals of of aa newly newly patpatented ented variety variety of of body body armor, armor, which which has has circuits circuits and and aa power power supply supply built built into into it, it, is is to to lighten lighten the the load load that that soldiers soldiers have have to to carry. carry. “This “This is is all all part part of of aa program program leading leading to to our our own own Iron Iron Man,” Man,” says says Val Val Horvatich, Horvatich, aa program program director director at at BAE, BAE, which which is is based based in in Arlington, Va. He keeps a life-size cutout of the film and comicĈÞ¦�²�í·²i;CÌw¥wwÆãC¦��w�ã�Ąw_÷í·÷í·�í�w�¦¬C²k_·¬�_� book character in his office for inspiration. T··¥_�CÞC_íwÞ�²��ã·�_w�·Þ�²ãÆ�ÞCí�·²Ì B ĈÛã�²ýw²í�·²�ã·²w·�í�w�Þãíí·�²íw�ÞCíww¦w_íÞ�_C¦_CÆCAE’s invention is one of the first to integrate electrical capabilities bilities and and aa power power supply supply directly directly into into body body armor. armor. Horvatich Horvatich says says the the built-in built-in battery battery can can power power all all the the gadgets gadgets aa soldier soldier or or police officer must carry, saving 20 to 60 percent of equipment Æ·¦�_w·�_wÞ¬÷ãí_CÞÞĀiãCý�²�õĆí·èĆÆwÞ_w²í·�wÓ÷�Ƭw²í weight. weight. The The new new technology, technology, which which is is scheduled scheduled for for release release in in December, December, also also has has sensors sensors and and wireless wireless capabilities capabilities that that will will automatically automatically notify notify aa soldier’s soldier’s team team in in the the event event of of an an attack. attack. L!�¥wC²C�ÞƦC²wí�Cí_C²_·²í�²÷w�Ā�²�þ�í�·²wkC¬C�wk ike an airplane that can continue flying with one damaged engine, engine, the the body body armor armor is is designed designed to to function function even even ifif part part of of itit is is destroyed. destroyed. A A microprocessor microprocessor built built into into the the device device will will detect detect the the hit hit and and shut shut down down the the damaged damaged quadrant quadrant but but keep keep the the others others operational. operational. “We “We call call that that ‘graceful ‘graceful degradation,’” degradation,’” Horvatich Horvatich says. says. He hopes this new armor will help troops enter and exit a field of w�·Æwãí��ã²wþCÞ¬·Þþ�¦¦�w¦ÆíÞ··Æãw²íwÞC²kwÿ�íC�w¦k·� battle —Anna battle the the same same way: way: gracefully. gracefully. —Anna Kuchment Kuchment

© 2010 Scientific American

December 2010, ScientificAmerican.com  25

© 2010 Scientific American

Advances A ARC RCHA HAEOLOGY EOLOGY

Out with a Bang Volcanic eruptions may have wiped out the Neandertals 02&&$01
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to 1-
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Courtesy OF of PIOTR Piotr NASKRECKI Naskrecki COURTESY

w h  at 
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Preppy Preppy in in Papua: This Papua: This pinkpinkand-green and-green katydid, katydid, aa large large grasshopper, grasshopper, isis one one of of 200 200 new new species species that that scientists scientists recently recently discovered discovered in in Papua Papua New New Guinea. Guinea. About About three three inches inches long, long, itit lives lives in in the the forest forest canopy canopy of of the the rugged rugged Muller Muller Range Range in in the the central-western central-western part part of of the the country. country. Harvard Harvard University’s University’s Piotr Piotr Naskrecki, Naskrecki, who who found found the the katydid katydid on on an an expedition expedition for for Conservation Conservation International, International, says says itit probably probably evolved evolved its its pink pink eyes as a form of camouflage. wĀwãCãC�·Þ¬·�_C¬·÷�C�wÌ “Leaves “Leaves in in tropical tropical forests forests are are often often dotted dotted with with fungi fungi and and epiphytes epiphytes [plants [plants that that grow grow on on other other plants], plants],”” he he says. says. ““Although Although these these eyes eyes may may look look striking striking to to us, us, when when the the katydid katydid sits sits motionless, motionless, they they help help with with the the illusion illusion that that itit isis just just aa leaf. leaf.”” Fortunately, Fortunately, they they didn’t didn’t fool fool Naskrecki. Naskrecki.  —Anna —Anna Kuchment Kuchment © 2010 Scientific American

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PUBL PUBL IC IC HEA HEA LTH LTH

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