Wednesday, December 21, 2011
The Welcome Song
Saturday, November 19, 2011
Lightest Material !
A team of engineers claims to have created the world's lightest material.
The substance is made out of tiny hollow metallic tubes arranged into a micro-lattice - a criss-crossing diagonal pattern with small open spaces between the tubes.
The researchers say the material is 100 times lighter than Styrofoam and has "extraordinarily high energy absorption" properties.
Potential uses include next-generation batteries and shock absorbers.
The research was carried out at the University of California, Irvine, HRL Laboratories and the California Institute of Technology and is published in the latest edition of Science.
"The trick is to fabricate a lattice of interconnected hollow tubes with a wall thickness 1,000 times thinner than a human hair," said lead author Dr Tobias Schaedler.
Low-density
The resulting material has a density of 0.9 milligrams per cubic centimetre.
By comparison the density of silica aerogels - the world's lightest solid materials - is only as low as 1.0mg per cubic cm.
The metallic micro-lattices have the edge because they consist of 99.99% air and of 0.01% solids.
The engineers say the material's strength derives from the ordered nature of its lattice design.
By contrast, other ultralight substances, including aerogels and metallic foams, have random cellular structures. This means they are less stiff, strong, energy absorptive or conductive than the bulk of the raw materials that they are made out of.
William Carter, manager of architected materials at HRL, compared the new material to larger low-density structures.
"Modern buildings, exemplified by the Eiffel Tower or the Golden Gate Bridge are incredibly light and weight-efficient by virtue of their architecture," he said.
"We are revolutionising lightweight materials by bringing this concept to the nano and micro scales."
Robust
To study the strength of the metallic micro-lattices the team compressed them until they were half as thick.
After removing the load the substance recovered 98% of its original height and resumed its original shape.
The first time the stress test was carried out and repeated the material became less stiff and strong, but the team says that further compressions made very little difference.
"Materials actually get stronger as the dimensions are reduced to the nanoscale," said team member Lorenzo Valdevit.
"Combine this with the possibility of tailoring the architecture of the micro-lattice and you have a unique cellular material."
The engineers suggest practical uses for the substance include thermal insulation, battery electrodes and products that need to dampen sound, vibration and shock energy.
Neutrinos beat light yet again!!!
The team which found that neutrinos may travel faster than light has carried out an improved version of their experiment - and confirmed the result. If confirmed by other experiments, the find could undermine one of the basic principles of modern physics.
Nothing's changed about the neutrinos, of course. But the Italian Institute for Nuclear Physics (INFN) researchers who shocked the world in September with a claim that they'd measured particles traveling faster than the speed of light now say a potential flaw in their experiment has been ruled out.
"New tests conducted at the Gran Sasso National Laboratory of INFN by the OPERA Collaboration, with a specially set up neutrino beam from CERN, confirm so far the previous results on the measurement of the neutrino velocity," the INFN team said in a statement released Friday. "The new tests seem to exclude part of potential systematic effects that could have affected the original measurement."
In September, an international team of scientists led by Dr. Sergio Bertolucci reported that particles they had been firing for several years from the CERN particle accelerator in Switzerland at detectors at the OPERA facility in Gran Sasso, Italy located about 450 miles away appeared to be arriving at their destination a fraction of a second earlier than the time it would take light to get there.
The particles, traveling through air, water, and rock, shouldn't have hit the Gran Sasso detectors any sooner than about 2.4 thousandths of a second after being fired, which is the time it would take light to travel the distance between the two points. Yet the CERN researchers reported that their neutrinos were getting to the target 64 nanoseconds faster—meaning that they were traveling faster than light, supposedly impossible according to Albert Einstein's Special Theory of Relativity.
That news sent the scientific community into an uproar, spawned breathless headlines questioning whether E still equaled MC squared, and gave new hope to anyone who has dreamt of faster-than-light travel to distant stars and planets.
The report also kick-started a movement to show that the results were somehow flawed—in short, science started doing what it's supposed to do when surprising and potentially groundbreaking results are published.
Among the possible flaws in the OPERA team's experiment pointed out by other scientists was the absence of energy loss by the neutrinos, which a pair of Boston University physicists argued would be detectable if the particles had traveled faster than light. Other scientists questioned whether the team had correctly accounted for the effects of relativity on the GPS satellites they used to measure the amount of time it took for the neutrinos to travel from point A to point B in their experiment.
The INFN team set out to re-run the neutrino experiment late last month. While results are not yet conclusive, the team says it's now ruled out a possible error in the measurement of the starting time for the neutrinos as they were fired from an accelerator in Geneva to the OPERA facility in Switzerland.
"A measurement so delicate and carrying a profound implication on physics requires an extraordinary level of scrutiny," said INFN president Fernando Ferroni. "The experiment OPERA, thanks to a specially adapted CERN beam, has made an important test of consistency of its result. The positive outcome of the test makes us more confident in the result, although a final word can only be said by analogous measurements performed elsewhere in the world."
Jacques Martino, director of the National Institute of Nuclear and Particle Physics of French CNRS, added that the team was re-checking other potential flaws in the original experiment.
"One of the eventual systematic errors is now out of the way, but the search is not over," Martino said. "There are more checks of systematics currently under discussion, one of them could be a synchronization of the time reference at CERN and Gran Sasso independently from the GPS.
Friday, November 18, 2011
Vatican miffed with Pope Kissing Imam (Ads)
The Vatican says it is taking legal action over the use of an ad showing Pope Benedict kissing a leading imam as part of a Benetton advertising campaign.
The Vatican move comes despite an announcement by the Italian clothing company that it was pulling the ad.
The ad, with its doctored image, is part of a global advertising campaign.
It consists of photo montages of political and religious leaders kissing each other on the mouth.
A statement said the Vatican had told its lawyers in Italy and around the world to "take the proper legal measures" to stop the use of the photo, even in the media.
It was not clear from the statement if the Vatican intended to sue Benetton directly for damages.
'Absurd'
The Vatican statement said the ad was "damaging to not only to dignity of the pope and the Catholic Church but also to the feelings of believers".
A spokesman for Egypt's al-Azhar institute, whose grand imam was pictured kissing the pope, described the advertisement as "irresponsible and absurd".
The spokesman, Mahmud Azab, told the French news agency AFP that the ad was so absurd that the institution was "still hesitating as to whether it should issue a response".
On Wednesday, Benetton pulled the ad showing Pope Benedict XVI kissing Egypt's Ahmed el Tayyeb, imam of the al-Azhar mosque in Cairo, after the Vatican launched a strong protest.
Other ads in the campaign feature US President Barack Obama kissing Chinese President Hu Jintao, and French President Nicolas Sarkozy with German Chancellor Angela Merkel.
In an initial protest on Wednesday, Vatican spokesman Federico Lombardi called the Benetton ad an "absolutely unacceptable use of the image of the Holy Father, manipulated and exploited in a publicity campaign with commercial ends.
"This shows a grave lack of respect for the pope, an offence to the feelings of believers, a clear demonstration of how publicity can violate the basic rules of respect for people by attracting attention with provocation," his statement said.
Shock ads
A large banner of the image showing the pope kissing the imam was hung from a bridge near the Vatican on Wednesday morning but later removed.
But on Thursday morning the picture was still in the window of a shop near Rome's Trevi Fountain, one of the most popular tourist sites in Rome.
The photo montage was still widely available on the internet on Thursday morning.
"We are sorry that the use of an image of the pontiff and the imam should have offended the sensibilities of the faithful in this way," Benetton said in a statement.
The purpose of the ad campaign, Benetton said in a statement, "was solely to battle the culture of hate in all its forms".
Benetton is no stranger to shock ad campaigns.
Previous controversial images it has used include death row inmates, a nun kissing a priest and a man dying of Aids.
Source: BBC
Saturday, October 8, 2011
Ozone in Venus?
Scientists have discovered that Venus has an ozone layer.
The thin layer, which is hundred of times less dense than the Earth's, was discovered by the European Space Agency's Venus Express craft,researchers report in the journal Icarus.
Until now, ozone layers have only been detected in the atmospheres of Earth and Mars.
The find could help astronomers refine their hunt for life on other planets.
The European spacecraft spied the ozone layer when focusing on stars through Venus' atmosphere.
The distant stars appeared fainter than expected, because the ozone layer absorbed some of their ultraviolet light.
The paper's lead author Franck Montmessin, of the LATMOS atmospheric research centre in France, explained that Venus' ozone layer sits 100km up; about three times the height of our own.
The ozone - a molecule containing three oxygen atoms - formed when sunlight broke down carbon dioxide in the Venusian atmosphere to form oxygen molecules.
On Earth, ozone, which absorbs much of the Sun's harmful UV-rays preventing them reaching the surface, is formed in a similar way.
However, this process is supplemented by oxygen released by carbon dioxide-munching microbes.
Ozoning in
Speaking of the international team's find, Hakan Svedhem, ESA project scientist for the Venus Express mission, said: "This ozone detection tells us a lot about the circulation and the chemistry of Venus's atmosphere.
"Beyond that, it is yet more evidence of the fundamental similarity between the rocky planets, and shows the importance of studying Venus to understand them all."
Some astrobiologists assume that the presence of oxygen, carbon, and ozone in an atmosphere indicates that life exists on a planet's surface.
The new results negate that assumption - the mere presence of oxygen in an atmosphere is now not enough evidence to start looking for life.
However, the presence of large quantities of these gases, as in the Earth's atmosphere, is probably still a good lead, the scientists said.
"We can use these new observations to test and refine the scenarios for the detection of life on other worlds," said Dr Montmessin.
Nobel Peace Prize 2011
This year's Nobel Peace Prize has been awarded jointly to three women - Liberian President Ellen Johnson Sirleaf, Liberian Leymah Gbowee and Tawakul Karman of Yemen.
They were recognised for their "non-violent struggle for the safety of women and for women's rights to full participation in peace-building work".
Mrs Sirleaf is Africa's first female elected head of state, Ms Gbowee is a Liberian peace activist and Ms Karman is a leading figure in Yemen's pro-democracy movement.
"We cannot achieve democracy and lasting peace in the world unless women achieve the same opportunities as men to influence developments at all levels of society," said Nobel Committee chairman Thorbjorn Jagland in Oslo.
Reading from the prize citation, he said the committee hoped the prize would "help to bring an end to the suppression of women that still occurs in many countries, and to realise the great potential for democracy and peace that women can represent".
German Chancellor Angela Merkel - deemed by Forbes the world's most powerful woman - called the award a "wise decision"
But Mrs Sirleaf's main rival in polls this coming Tuesday, Winston Tubman, told the BBC she did not deserve the prize and was a "warmonger".
2011 Peace Prize laureates
Ellen Johnson Sirleaf - President of Liberia
- first democratically elected female African head of state
- seen as a reformer and peacemaker after Liberia's civil war
Tawakul Karman - Yemeni pro-democracy activist
- journalist and key leader of protests against President Ali Abdullah Saleh
- first Arab woman to be awarded the peace prize
Leymah Gbowee - Liberian peace activist
- mobilised female opposition to Liberia's civil war
- encouraged women to participate in political process
Arab Spring
Mrs Karman heard of her win from protest camp Change Square in the capital Sanaa, where she has been living for several months calling for President Ali Abdullah Saleh to stand down.
She was recognised for playing a leading part in the struggle for women's rights in Yemen's pro-democracy protests "in the most trying circumstances" and is the first Arab woman to win the prize.
As the head of Yemeni organisation Women Journalists without Chains, Mrs Karman has been jailed several times.
Mrs Karman told BBC Arabic she was dedicating it to "all the martyrs and wounded of the Arab Spring" - the wave of unrest which has swept the Middle East and North Africa in the past year - and to "all the free people who are fighting for their rights".
Mr Jagland said the oppression of women was "the most important issue" in the Arab world and that awarding the prize to Ms Karman was "giving the signal that if it [the Arab Spring] is to succeed with efforts to make democracy, it has to include women".
'Iron Lady'
Ms Sirleaf, 72, who had been widely tipped as a winner, said the award was "for all Liberian people" and a recognition of "many years of struggle for justice".
She was elected in 2005, following the end of Liberia's bloody and ruinous 14-year civil war.
Upon coming to office, the US-educated economist and former finance minister - known as Liberia's "Iron Lady" - pledged to fight corruption and bring "motherly sensitivity and emotion to the presidency".
Mrs Sirleaf is standing in Tuesday's election, having previously said she would only hold the presidency for one term.
Her rival Mr Tubman denounced the award, saying she had "brought war here".
She had initially backed the rebels of Charles Taylor - currently on trial for war crimes in The Hague.
Although she has apologised, Liberia's Truth and Reconciliation Commission recommended that she be barred from holding public office for 30 years.
"I did more to stop the war than she did because she was for continuing the war," Mr Tubman said.
"Now that the war has stopped she wants to continue on top of the country as though she is some liberator. She is not."
He told AFP news agency the timing of the award was "provocative".
But Archbishop Desmond Tutu and U2 singer Bono welcomed Mrs Sirleaf's honouring, with Mr Tutu telling AFP: "Woo hoo. She deserves it many times over. She's brought stability to a place that was going to hell."
Her compatriot Mrs Gbowee was a leading critic of the violence during the Liberian civil war, mobilising women across ethnic and religious lines in peace activism and encouraging them to participate in elections.
In 2003 she led a march through the capital, Monrovia, demanding an end to the rape of women by soldiers.
The Nobel Committee said she had "worked to enhance the influence of women in West Africa during and after war".
Mrs Gbowee told the BBC's Focus on Africa programme: "I am confused. I am humbled. This is the first time in the 39 years of my life that I am out of words.
"This is a victory for women rights everywhere in the world. What could be better then three women winning the prize?
"This is the recognition that we hear you, we see you, we acknowledge you."
The women will share the $1.5m (£1m) prize money.
The BBC's world affairs correspondent Mike Wooldridge says that the Nobel Peace Prize originally recognised those who had already achieved peace, but that its scope has broadened in recent years to encourage those working towards peace and acknowledge work in progress.
The Nobel committee received a record 241 nominations for this year's prize - among the individuals and groups believed to have been put forward were the European Union, Facebook founder Mark Zuckerberg and key cyber dissidents in the Arab Spring movement.
Saturday, October 1, 2011
Friday, September 23, 2011
Faster than Light?
Puzzling results from Cern, home of the LHC, have confounded physicists - because it appears subatomic particles have exceeded the speed of light.
Neutrinos sent through the ground from Cern toward the Gran Sasso laboratory 732km away seemed to show up a tiny fraction of a second early.
The result - which threatens to upend a century of physics - will be put online for scrutiny by other scientists.
In the meantime, the group says it is being very cautious about its claims.
"We tried to find all possible explanations for this," said report author Antonio Ereditato of the Opera collaboration.
"We wanted to find a mistake - trivial mistakes, more complicated mistakes, or nasty effects - and we didn't," he told BBC News.
"When you don't find anything, then you say 'Well, now I'm forced to go out and ask the community to scrutinise this.'"
Caught speeding?
The speed of light is the Universe's ultimate speed limit, and much of modern physics - as laid out in part by Albert Einstein in his special theory of relativity - depends on the idea that nothing can exceed it.
Thousands of experiments have been undertaken to measure it ever more precisely, and no result has ever spotted a particle breaking the limit.
But Dr Ereditato and his colleagues have been carrying out an experiment for the last three years that seems to suggest neutrinos have done just that.
Neutrinos come in a number of types, and have recently been seen to switch spontaneously from one type to another.
The team prepares a beam of just one type, muon neutrinos, sending them from Cern to an underground laboratory at Gran Sasso in Italy to see how many show up as a different type, tau neutrinos.
In the course of doing the experiments, the researchers noticed that the particles showed up a few billionths of a second sooner than light would over the same distance.
The team measured the travel times of neutrino bunches some 15,000 times, and have reached a level of statistical significance that in scientific circles would count as a formal discovery.
But the group understands that what are known as "systematic errors" could easily make an erroneous result look like a breaking of the ultimate speed limit, and that has motivated them to publish their measurements.
"My dream would be that another, independent experiment finds the same thing - then I would be relieved," Dr Ereditato said.
But for now, he explained, "we are not claiming things, we want just to be helped by the community in understanding our crazy result - because it is crazy".
"And of course the consequences can be very serious."
Source: BBC Online
Saturday, August 27, 2011
World's Greatest Sportsperson?
Is it possible to work out which living athlete is the best? Mathematician Rob Eastaway, co-author of The Hidden Mathematics of Sport, investigates.
The case for Indian batsman Sachin Tendulkar is certainly strong. His international career has spanned an astonishing 22 years, during which time he has never been dropped from the Indian Test side.
The "Little Master" has scored more runs and notched up more international hundreds than anyone else in the history of the game, although cricket fans will always be compelled by Donald Bradman's famous 99.94 batting average. And it's not just that he has scored more, it's the huge margin by which he tops the table.
Longevity and the accumulation of trophies is certainly an important factor in making greatness, but it is surely not the only one. After all, if you're only looking at durability at the top, then Tendulkar is outstripped by US golfer Tom Watson, who has been a serious challenger in the Open since 1975.
The trouble is, there are so many statistical ways to measure greatness.
One is to pick out those sportsmen and women who for a period of time are in a different class from their peers. The goal-scoring feats of Lionel Messi make him a candidate, but statistical measurements of footballers are always tricky, not least because it can be hard to disentangle one player's performance from the contributions of his team mates.
Champion of champions?
- Sachin Tendulkar - achieved 99 centuries in international cricket
- Usain Bolt - world record and Olympic record holder in the 100m, the 200m and the 4×100m relay
- Tom Watson - five-time Open winner, challenged at the top level since 1975
- Phil "The Power" Taylor - won a record 15 world darts championships
- Jenny Thompson - won more swimming medals and gold medals than any woman in Olympic history
The feats within individual sports are easier to assess, and in terms of quantum leaps, can anyone rival Usain Bolt?
The 100 metre sprint is the pinnacle of athletics where the world records normally mean shaving 1/100th of a second off the previous best time. Yet Bolt has broken that record not just once but three times, and in his most recent, mathematicians reckoned he could have knocked more than a tenth of a second off the record time had he not slowed up at the finish because his shoelace was undone.
Great sportsmen are head and shoulders ahead of the competition. In Bolt's case it's head, shoulders and a couple of strides too.
Or you can take a look at a sport's world rankings. Every sport uses a different system for rankings its members, but all of them are based on some form of objective, mathematical model.
To identify the world's greatest, why not look at which sportsman has managed to spend the longest amount of time as world number one. Tiger Woods managed to be top of the golf rankings for over 10 years, before his recent fall from grace. By this measure, though, there's a British sportsman who pips Tiger for the title.
Phil "The Power" Taylor has had an almost unbroken position as world number one in darts since 1998. And yes, darts is now officially a sport.
We can of course let the market decide. If a sportsman earns a lot of money, it must reflect his global appeal and success.
David Beckham, surely a great, has earned tens of millions over his career.
Yet on this score, the world's greatest sportsmen at the moment could be Alex Rodriguez. He's paid around $30m (£18m) per year, and that's before all the product endorsements. He plays baseball.
But can he really be called the world's greatest when his name barely registers in public consciousness outside his own country?
Of course greatness also depends on many things that are hard to measure - charisma, style and an ability to hit the headlines, for example.
With all this complex and sometimes conflicting data, perhaps we should put our trust in the wisdom of crowds.
Despite the diverse and often ill-informed opinion of the public, put enough people together and they often manage to come up with the right answer.
And if we ask the crowd who is the greatest sportsman, I think I know who'll come out top. Sachin Tendulkar.
Why? He would win by sheer weight of population. There are over a billion people in India who have little sporting interest other than cricket. And a billion people can't be wrong - can they?
Source: BBC
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