In neutrino gear
Particles heavier than light may travel faster than light. So why should Einstein fans worry?india Updated: Sep 26, 2011 21:22 IST
For a legendary equation that few of us really comprehend, the news that Albert Einstein’s E=mc2 may not be correct comes as a secret relief to most of us.
After all, there’s no point trying to fathom something that’s, well, wrong.
To be fair to Herr Einstein, when he dashed off his paper that would become the special theory of relativity to the scientific journal Annalen der Physik in 1905, he hadn’t put the mass-energy equivalence bit in.
He sent off a three-page supplement later whose accuracy he was a bit unsure of.
Last week, with physicists observing subatomic particles that apparently travelled faster than the speed of light (299,792.458 km per second), the equation that Einstein had written down four paragraphs from the end of the supplement could be proved wrong.
So who or what has made Einstein come perilously close to sticking out his tongue in embarrassment?
An electrically charged neutron, elementary subatomic particle with a tiny mass called the neutrino (small neutral one).
In 2009, 2010 and 2011, scientists at CERN — the European Organisation for Nuclear Research — had slung neutrinos in a particle accelerator in Geneva that were ‘caught’ in Gran Sasso in Italy. What made scientists suspect something was wrong with the experiment was the speed of the neutrinos: 299798.454 kms per second, 20 parts per million above the speed of light.
In physics, that’s like finding Jesus was not conceived immaculately.
So how has the ghostly neutrino challenged Einstein?
The speed of neutrinos is linked to their masses. According to Herr Einstein’s special theory of relativity, neutrinos can reach the speed of light only if they are massless.
The Geneva-Gran Sasso bunch of 15,000 neutrinos not only had mass but also broke the speed limit.
Scientists are double-checking but E=mc2, despite its beauty, may find itself under pressure to explain itself.
First Published: Sep 26, 2011 21:20 IST