The Malaysian Insider :: Features
The Malaysian Insider :: Features |
| Success or failure: For Einstein, it’s all relative Posted: 30 Sep 2011 01:50 AM PDT  Einstein pioneered the theory of relativity. — AFP pic The finding was a shock. The speed of light was enshrined in 1905 by Einstein as the Universe's speed limit. Today, physicists almost everywhere accept it as such. Could the great man have got it terribly wrong? But soon after this shadow fell across Einstein's reputation, another experiment came along which has validated — magnificently and on a cosmological scale — another of his landmark ideas. According to Einstein's general theory of relativity, light emitted from stars and galaxies is slightly tugged by gravity from celestial bodies. Danish astronomers have put the theory to the test in measuring light emitted by galactic "clusters." These are sectors of deep space which are packed with thousands of galaxies, held together by their own gravity. Their density and mass should thus have a perceptible gravitational effect on the light they emit. University of Copenhagen cosmologist Radek Wojtak and colleagues analysed light from around 8,000 of these clusters. They were looking for variations in "redshift," a measurement of the shift in light. As the Universe expands, light from a star becomes slightly redder as its wavelength lengthens, indicating a widening distance between the star and Earth. Wojtak's team measured the wavelength of light from galaxies lying in the middle of the galactic clusters, where the densest gravitational pull prevailed, and those lying on the more sparsely-populated periphery. "We could measure small differences in the redshift of the galaxies and see that the light from galaxies in the middle of a cluster had to 'crawl' out through the gravitational field, while it was easier for the light from the outlying galaxies," said Wojtak. They then measured the galaxy cluster's total mass to get a fix on its gravitational potential. "The redshift of light is proportionately offset in relation to the gravitational influence from the galaxy cluster's gravity," said Wojtak. "In that way, our observations confirm the theory of relativity." The findings do not negate popular theories about dark matter and dark energy, the enigmatic phenomena that account for almost all over the matter in the Universe. Until now, Einstein's theory of the impact of gravity on light had only been tested from within the Solar System itself — essentially by measuring light from the Sun that was "redshifted" by the gravitational pull of Mercury. On September 22, physicists reported that neutrinos can travel faster than light, a finding that — if verified — would blast a hole in Einstein's theory of special relativity. In experiments conducted between the European Centre for Nuclear Research (CERN) in Switzerland and a laboratory in Italy, the particles were clocked at 300,006 km per second, about six km/sec faster than the speed of light, the researchers said. The physicists themselves admitted they were quite flummoxed by the findings and other experts are sceptical, suggesting a problem in measurement techniques or equipment. Wojtak's research is released on Wednesday by Nature, the British scientific journal. — AFP/Relaxnews |
| Wasabi alarm, beetle sex win Ig Nobel spoof prizes Posted: 29 Sep 2011 07:37 PM PDT CHICAGO, Sept 30 — Prognosticators who predicted the end of the world and got it wrong, scientists who built a wasabi fire alarm, and researchers who studied how the urge to urinate affects decision-making were among the winners of spoof Ig Nobel prizes yesterday. The annual prizes, meant to entertain and encourage scientific research, are awarded by the Journal of Improbable Research as a whimsical counterpart to the Nobel Prizes, which will be announced next week.  Ig Nobel in years past: Dr Elena Bodnar demonstrates her brassiere that can quickly convert into a pair of protective face masks, helped by Nobel laureates Wolfgang Ketterle (left), Orhan Pamuk, and Paul Krugman (right). Former winners of the real Nobel prizes hand out the prizes at a ceremony held at Harvard University in Massachusetts. A personal favourite of Marc Abrahams, editor of the Annals and architect of the Ig Nobels, is this year's winner for the Public Safety Prize, which went to John Senders of the University of Toronto, Canada. Senders and colleagues conducted experiments to see how distractions — in this case a helmet with a visor that repeatedly flaps over a person's face — affects attention during highway driving. "They put this on someone while this visor is flapping and blinding them," Abrahams said. Remarkably, the driver fared quite well, he said. Peter Snyder, a professor of neurology at Brown University in Providence, Rhode Island, was part of two research teams who won the Medicine Prize for studying how the urge to urinate affects decision-making. Snyder's team set up an experiment in which volunteers did computer tests and then periodically drank 250ml of water as the scientists measured the effects of the volunteers' gradually swelling bladders on attention and working memory. The aim was to see who could last the longest before bolting for the toilet. The study found that attention and working memory suffer when you are so focused on having to pee. "When you gotta go, you gotta go," Snyder said. Abrahams said Ig Nobel judges spent much of the year sifting through piles of nominations, and the selection process could become heated. "We have a devil of a time picking them. I have to step in and remind them what prize it is we are arguing about." Other winners: — Arturas Zuokas, the mayor of Vilnius, Lithuania, winner of the Peace Prize for showing that the problem of illegally parked luxury cars can be solved by running them over with an armoured tank. — John Perry of Stanford University for his Theory of Structured Procrastination, which holds that procrastinators can be motivated to do important things as long as they are doing them as a way of avoiding something even more important. — Anna Wilkinson of the University of Lincoln in the United Kingdom, Natalie Sebanz of Radboud University Nijmegen in the Netherlands and others, for their study that found no evidence of contagious yawning in red-footed turtles. — Makoto Imai, Naoki Urushihata, Hideki Tanemura, Yukinobu Tajima, Hideaki Goto, Koichiro Mizoguchi and Junichi Murakami of Japan for determining the ideal density of airborne wasabi — a pungent horseradish — to awaken sleeping people and for applying this knowledge to invent a wasabi fire alarm. — Karl Halvor Teigen of the University of Oslo, Norway, for trying to understand why, in everyday life, people sigh. — Americans Dorothy Martin, who predicted the world would end in 1954; Pat Robertson, who predicted the world would end in 1982; Elizabeth Clare Prophet, who predicted the world would end in 1990; and Harold Camping, who predicted the world would end on September 6, 1994, and on October 21, 2011; Lee Jang Rim of Korea, who predicted the world would end in 1992; Shoko Asahara of Japan. who predicted the world would end in 1997; Credonia Mwerinde of Uganda, who predicted the world would end in 1999 — for teaching the world to be careful when making mathematical assumptions and calculations. A replay of the awards ceremony can be seen here. — Reuters |
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