Monday, 24 March 2014

Window on first fraction of second 19/3/2014 THE OZ

Video missing - I cannot paste it: see the link - view it on The Oz website.
There is also variation between th newspaper and web story - which I have tried to expand to reader advantage,
G Seidner

Window on first fraction of second



RIPPLES of gravity leftover from the Big Bang some 13.8 billion years ago have been detected for the first time by scientists, bolstering theories that the universe underwent a furious rate of inflation in its first trillionth, of a trillionth of a trillionth of a second.
The major discovery represents one of the most profound insights in decades to emerge from the field of cosmology and will open new avenues of understanding the origins of the universe as well as helping to explain why matter appears so evenly spread throughout the cosmos. 

"This is opening a window on what we believe to be a new regime of physics - the physics of what happened in the first unbelievably tiny fraction of a second in the Universe," said John Kovac from the Harvard-Smithsonian Center for Astrophysics and leader of the BICEP2 team that made the discovery.

"Detecting this signal is one of the most important goals in Cosmology today. A lot of work by a lot of people has led up to this point."

The landmark breakthrough was announced yesterday by scientists from the Harvard-Smithsonian Center for Astrophysics who spent the past three years analysing data from an experiment known as Background Imaging of Cosmic Extra Galactic Polarization or BICEP2, which used a radio telescope a the South Pole to target a slither of sky where they were able to detect faint gravitational distortions or swirls in the polarisation of the Cosmic Microwave Background - the faint radioactive glow left from the Big Bang when the universe was 380,000 years old and as hot as the sun's surface.
Scientists consider these patterns, depicting the tug of gravitational waves predicted in Albert Einstein's theory of general relativity nearly a century ago , as the smoking gun for the Cosmic Inflation theory.
The theory posits that less than a trillionth of a second after the Big Bang, the universe expanded by a factor of 100 trillion, trillion times.

Scientists say that without cosmic inflation the universe would look lumpier than it does, much like a deflated balloon. However inflation provides an answer to why the faint glow of the universe and the distribution of its matter is smooth, much like blowing up a balloon smooths out ripples on it's surface. The team of scientists from the Harvard - Smithsonian Centre for Astrophysics said the data they collected from the BICEP 2 experiment came with ''five sigma certainty''- which means there is only one chance in near two million that a random fluctuation would yield the same result.  
The experiment used a radio telescope based at the South Pole to target a tiny slither of sky where scientists were able to detect faint gravitational distortions or swirls in the polarisation of the Cosmic Microwave Background - the faint radioactive glow left over from the Big Bang when the universe was just 380,000 years old and as hot as the surface of the Sun.

Gravitational waves squeeze space as they travel, and this squeezing produces a distinct pattern in the cosmic microwave background said the US-based scientists. Because these waves have a "handedness," much like light waves, they can have left- and right-handed polarisations.

"The swirly pattern is a unique signature of gravitational waves because of their handedness. This is the first direct image of gravitational waves across the primordial sky," said BICEP2’s co-leader Chao-Lin Kuo.

It’s these swirly patterns representing the tug of gravitational waves - first predicted in Albert Einstein's theory of general relativity nearly a century ago - that scientists now consider to be the smoking gun for the Cosmic Inflation theory which posits that less than a trillionth of a second after the Big Bang, the universe expanded by a factor of 100 trillion, trillion times in barely the blink of an eye.



"This work offers new insights into some of our most basic questions: Why do we exist? How did the universe begin? These results are not only a smoking gun for inflation, they also tell us when inflation took place and how powerful the process was," said Harvard theorist Professor Avi Loeb.



This is the threshold for certainty before you can claim a discovery in particle physics.

If confirmed by other experts, it’s expected the work could be a contender for the Nobel Prize.

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