A conventional maze is a set of walls or hedges enclosing a roughly rectangular plot of space. One enters from outside of the rectangle and the goal is to exit somewhere else. A well-known strategy for defeating such a maze is to put your left hand on the wall and walk forward, always touching the wall with your left hand. Eventually you will reach the exit. For example consider this simple maze:...
The following essay is reprinted with permission from The Conversation, an online publication covering the latest research. On May 7, France will choose its next president. In the first round of voting on April 23, voters rejected candidates from the country’s established parties, lifting former investment banker Emmanuel Macron and nationalist Marine Le Pen to the runoff. The vote capped a swift rise for Le Pen’s National Front party, whose anti-immigrant views had long interfered with its general success....
Editor’s Note: This story was originally published in the May 2007 issue of Scientific American; we’re posting it now due to new findings released today pinpointing methane sources on Mars. Of all the planets in the solar system other than Earth, Mars has arguably the greatest potential for life, either extinct or extant. It resembles Earth in so many ways: its formation process, its early climate history, its reservoirs of water, its volcanoes and other geologic processes....
Scientific truths are always provisional at some level. We once believed that the continents were fixed on the surface of Earth; now we know they move. We thought the universe was static; now we know it is expanding. We thought margarine was healthier than butter and that hormone-replacement therapy was the right treatment for vast numbers of postmenopausal women; now we know better. But while scientists do not know everything, there is plenty they do know....
The sage-green, waist-high shrub guayule might look like just one of the many scraggly bushes that dot the hills and valleys of the Chihuahuan Desert in Mexico and the southwestern U.S. But its nondescript stalks and leaves harbor a panoply of botanical treasures, including rubber that Indigenous people used hundreds of years ago to make balls for games. For decades, researchers have been investigating guayule (Parthenium argentatum) as a potential commercial source of natural rubber....
Four hundred years ago this year, two events marked what scientists and historians today regard as the birth of modern astronomy. The first of them, the beginning of Galileo’s telescopic observations, has been immortalized by playwrights and authors and widely publicized as the cornerstone anniversary for the International Year of Astronomy. Through his looking glass, the Italian astronomer saw the mountains and valleys of the moon, the satellites of Jupiter, and sunspots—observations that would play a huge role in discrediting the prevailing, church-endorsed view of an Earth-centered cosmos....
Trial and error, followed by fast-tracked adjustments, best describes Singapore’s business plan. In the late 1960s, the country’s fledgling government pursued industrialization through importation—positioning itself as a supportive base camp for multinational corporations and value-added manufacturing. Singapore’s newly formed business-courting apparatus, the Economic Development Board (EDB), created an enticing environment for foreign business, and Western companies—including Texas Instruments, Hewlett-Packard and General Electric—started pouring in. This fueled huge business and economic growth, until difficult times drove that to a halt early in this century....
Click here for a full list of our coverage of the 2008 Consumer Electronics Show. LAS VEGAS—Bill Gates, the co-founder and current chairman of software powerhouse Microsoft, has given a keynote lecture at the Consumer Electronics Show for eight years in a row, or 11 times in total. For his final turn at the lectern, he chose to emphasize his vision of what he referred to as “the second digital decade....
One of the biggest challenges of learning a new language is hearing and reproducing unfamiliar sounds. Often teachers focus on vocabulary and practicing simple sentences. But new research suggests people could master languages more rapidly by practicing pronunciation first. This strategy can help in identifying the subtle distinctions between similar phonemes, or speech sounds, across languages. For example, below are 10 sibilant (sounds such as s, sh, ch, zh) syllables from English, French, Russian and Hungarian....
IN THE PAST FEW YEARS, much has been written about ways to foster creativity in individuals. But groups of people—at the office, in church committees, among volunteer organizations—may need just as much help finding a collective spark. Here are some tricks, beginning with a word of caution. Forbid criticism. No group will generate brilliant insights if participants are hostile to crazy ideas. Collective imagination can flourish only if everyone feels free of anxiety and full of trust....
Classification is never easy. Whether it’s monkey species, astronomical objects or elementary particles, there are seemingly endless ways to organize and group things. For centuries biologists have used “family tree” diagrams as their approach of choice for tracing living organisms’ lineages. And now astronomers are borrowing from biology to classify stars this way, too. DNA can reveal how organisms are related, and the chemical makeup of a star can similarly be used to determine its ancestry....
Tobacco plants produce abundant biomass in more than 100 countries and could – with certain genetic modifications – be used to produce abundant biofuels, researchers say. Researchers at the Biotechnology Foundation Laboratories of Thomas Jefferson University in Philadelphia, have successfully tested genetic manipulations to increase oil accumulation in the leaves of tobacco plants, according to a paper published online in Plant Biotechnology Journal. “In the search for alternative biofuel plant resources, tobacco has been largely overlooked as it is considered primarily as an expensive crop grown for smoking,” researchers Vyacheslav Andrianov and Nikolai Borisjuk wrote....
In the winter of 1994, a young man in his early twenties named Tim was a patient in a London psychiatric hospital. Despite a happy and energetic demeanor, Tim had bipolar disorder and had recently attempted suicide. During his stay, he became close with a visiting U.S. undergraduate psychology student called Matt. The two quickly bonded over their love of early-nineties hip-hop and, just before being discharged, Tim surprised his friend with a portrait that he had painted of him....
The U.S. covers a vast array of ecosystems, from Alaska’s Arctic tundra to Florida’s tropical swamps, with prairies, snow-capped peaks and deserts in between. Like the rest of the planet, humans are putting those ecosystems under enormous strain as we convert land to agriculture and urban development, release myriad pollutants and burn fossil fuels that spew heat-trapping greenhouse gases. But fast action can stem the resulting loss of biodiversity and give animals, plants and the ecosystems they make up the best possible chance to adapt....
Imagine you’re standing on a footbridge over some trolley tracks. Below you, an out-of-control trolley is bearing down on five unaware individuals standing on the track. Standing next to you is a large man. You realize that the only way to prevent the five people from being killed by the trolley is to push the man off the bridge, into the path of the trolley. His body would stop the trolley, saving the lives of the five people further down the track....
“In the past few years both the methods of ‘lie detection’ and the polygraph itself have been subjected to increasing scrutiny. Although the polygraph was developed as an aid in police work, enterprising practitioners have long since discovered new applications for the device, and since about 1950 the polygraph has become firmly established in industry and government. There are some 500 commercial polygraph firms. Many companies retain polygraph examiners not only to investigate specific losses but also to conduct routine preemployment interviews in an attempt to identify applicants who are likely to be disloyal to the company....
Mice are at their best at night. But a new analysis suggests researchers often test the nocturnal creatures during the day—which could alter results and create variability across studies—if they record time-of-day information at all. Of the 200 papers examined in the new study, more than half either failed to report the timing of behavioral testing or did so ambiguously. Only 20 percent reported nighttime testing. The analysis was published in Neuroscience & Biobehavioral Reviews....
Just how many individuals on death row are incorrectly convicted? The question has dogged attorneys and civil rights advocates for years, but a simple answer is almost impossible because few wrongful cases are ever overturned. A new analysis is adding a level of much-needed detail, and it concludes that more than twice as many inmates were wrongly convicted and sentenced to death than have been exonerated and freed. Borrowing a statistical method often used to evaluate whether new medical therapies help patients survive, a team of researchers has concluded that about 4....
The following essay is reprinted with permission from The Conversation, an online publication covering the latest research. In the wake of car- and truck-based attacks around the world, most recently in New York City, cities are scrambling to protect busy pedestrian areas and popular events. It’s extremely difficult to prevent vehicles from being used as weapons, but technology can help. Right now, cities are trying to determine where and how to place statues, spike strip nets and other barriers to protect crowds....
This years Nobel Prize in physics is split between three scientists in the field of optics. They are Roy Glauber of Harvard University in Cambridge, Mass., John Hall of the University of Colorado and National Institute of Standards and Technology in Boulder, Colo., and Theodor Hnsch of the Ludwig Maximilian University in Munich and the Max Planck Institute for Quantum Optics in Garching, Germany. Glauber received the award for his theoretical description of the behavior of light particles; Hall and Hnsch used that theory to develop a precision laser than can measure the color of the light of atoms and molecules, which can help identify the composition of materials....
