from the Agence France-Presse
Stockholm, Sweden
Translation Doxa-l
THE NOBEL PRIZE FOR PHYSICS GIVEN TO THREE SPECIALIZED RESEACHERS ON THE EXPANSION OF THE UNIVERSE
Type 1a supernova are considered standard candles for the universe, star explosions whose luminosity is well known and are then used to measure distance in the universe.
The Nobel prize in physics 2011 was awarded Tuesday to three astrophysicists for having turned cosmology upside-down with ‘the discovery of the accelerated expansion of the universe’, a «crazy result» made posible by the observation of very distant exploding stars, supernovae.
The laureats, who published their revolutionary observations in 1998 in two dictinct studies, are Saul Perlmutter, of the Supernova Cosmology Project on the one hand, and Brian P. Schmidt and Alan G. Reiss from the High-z Supernova Search Team on the other.
The three researchers were tracking a very precise type of supernovae, said 1a, which are created by very dense star residues.
These supernvae emit a caracteristic luminosity well known of astronomers, capable of equaling entire galaxies, and thus serving as measurement standards for distances in the universe, which has earned them the nickname of standard-candles.
To their great surprise, in1998, the three astrophysicists found in the cosmos more than fifty 1a supernovae with luminosity less bright than what it should have been.
Their conclusion, since then corraborated by other observations and works, is that the expansion of the universe has benn accelerating since the Big Bang (some 14 billion years ago). For more than a century, the scientific community had well expected a contrary finding, starting from the principle that gravity would slow down expansion.
A conclusion so odd that the Australo-American researcher Brian Schmidt, 44, from the High-z Supernova Search Team and teacher at the Australian National University, had trouble believing it himself.
An unexpected result.
«Adam Reiss and I tried to understand this crazy finding, we were desperately trying to find what went wrong (...) It seemed just too crazy to be true. We were a bit scared» he recounted to journalists questioning him from Stockholm via the Internet.
«Our work on supernova, which aimed initially at measuring the decelleration of the expansion of the universe due to gravity, in effect showed its acceleration», summed up Saul Perlmutter on his web page from the university of California, Berkeley.
He further explains : «This unexpected result suggests that the major part of the universe - some 75% - could be made up of a hitherto unknown energy, now called ‘dark energy’, reponsible for the acceleration of its expansion».
A ‘dark’ or ‘black’ energy, which would have governerned the dynamics of the universe for a few billion years. Starting from the discovery of our three Nobel prize-winners 2011, it would function as an anti-gravity, that is a force of repulsion, which has opened up for physicists new fields of research for the comprehension of the cosmos.
Adam Reiss teaches at John Hopkins University in Baltimore (US). The two members of the High-z supernova Search Team share their Nobel prize with Saul Perlmutter, of the Supernova Cosmology Project and Professor at the University of California at Berkeley.
The three men are to receive their prize at an official ceremony at Stockholm on December 10, anniverary date of the death of Alfred Nobel.
Stockholm, Sweden
Translation Doxa-l
THE NOBEL PRIZE FOR PHYSICS GIVEN TO THREE SPECIALIZED RESEACHERS ON THE EXPANSION OF THE UNIVERSE
Type 1a supernova are considered standard candles for the universe, star explosions whose luminosity is well known and are then used to measure distance in the universe.
The Nobel prize in physics 2011 was awarded Tuesday to three astrophysicists for having turned cosmology upside-down with ‘the discovery of the accelerated expansion of the universe’, a «crazy result» made posible by the observation of very distant exploding stars, supernovae.
The laureats, who published their revolutionary observations in 1998 in two dictinct studies, are Saul Perlmutter, of the Supernova Cosmology Project on the one hand, and Brian P. Schmidt and Alan G. Reiss from the High-z Supernova Search Team on the other.
The three researchers were tracking a very precise type of supernovae, said 1a, which are created by very dense star residues.
These supernvae emit a caracteristic luminosity well known of astronomers, capable of equaling entire galaxies, and thus serving as measurement standards for distances in the universe, which has earned them the nickname of standard-candles.
To their great surprise, in1998, the three astrophysicists found in the cosmos more than fifty 1a supernovae with luminosity less bright than what it should have been.
Their conclusion, since then corraborated by other observations and works, is that the expansion of the universe has benn accelerating since the Big Bang (some 14 billion years ago). For more than a century, the scientific community had well expected a contrary finding, starting from the principle that gravity would slow down expansion.
A conclusion so odd that the Australo-American researcher Brian Schmidt, 44, from the High-z Supernova Search Team and teacher at the Australian National University, had trouble believing it himself.
An unexpected result.
«Adam Reiss and I tried to understand this crazy finding, we were desperately trying to find what went wrong (...) It seemed just too crazy to be true. We were a bit scared» he recounted to journalists questioning him from Stockholm via the Internet.
«Our work on supernova, which aimed initially at measuring the decelleration of the expansion of the universe due to gravity, in effect showed its acceleration», summed up Saul Perlmutter on his web page from the university of California, Berkeley.
He further explains : «This unexpected result suggests that the major part of the universe - some 75% - could be made up of a hitherto unknown energy, now called ‘dark energy’, reponsible for the acceleration of its expansion».
A ‘dark’ or ‘black’ energy, which would have governerned the dynamics of the universe for a few billion years. Starting from the discovery of our three Nobel prize-winners 2011, it would function as an anti-gravity, that is a force of repulsion, which has opened up for physicists new fields of research for the comprehension of the cosmos.
Adam Reiss teaches at John Hopkins University in Baltimore (US). The two members of the High-z supernova Search Team share their Nobel prize with Saul Perlmutter, of the Supernova Cosmology Project and Professor at the University of California at Berkeley.
The three men are to receive their prize at an official ceremony at Stockholm on December 10, anniverary date of the death of Alfred Nobel.
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