Caltech has the BICEP telescope (Background Imaging of Cosmic Extragalactic Polarization). BICEP2 is an experiment designed to measure the polarization of the cosmic microwave background (CMB) to unprecedented precision, and in turn answer crucial questions about the beginnings of the Universe. BICEP operates at 100 GHz and 150 GHz at angular resolutions of 1.0° and 0.7°, respectively, with an array of 98 polarization-sensitive detectors, mapping a large region of the sky around the South Celestial Pole. The telescope successfully deployed to the Amundsen-Scott South Pole Station in November 2005 and will take data until the end of 2008.
UPDATE - Wired - The team at the Harvard-Smithsonian Center for Astrophysics has announced they've found "The First Direct Evidence of Cosmic Inflation." The scientists say that after three years of research and staring at a patch of sky, they have found and observed waves (signals of light) that are the "smoking gun" of cosmic inflation and echoes of the Big Bang theory.
The scientists have data that represents the first images of gravitational waves, or ripples in space-time. In the plainest English possible: these waves have been described as the "first tremors of the Big Bang" and were created fractions of a second after our universe came to be. They were part of Albert Einstein's General Theory of relativity, but have never been seen.
Since the cosmic microwave background is a form of light, it exhibits all the properties of light, including polarization. On Earth, sunlight is scattered by the atmosphere and becomes polarized, which is why polarized sunglasses help reduce glare. In space, the cosmic microwave background was scattered by atoms and electrons and became polarized too.
"Our team hunted for a special type of polarization called 'B-modes,' which represents a twisting or 'curl' pattern in the polarized orientations of the ancient light," said co-leader Jamie Bock (Caltech/JPL).
Gravitational waves squeeze space as they travel, and this squeezing produces a distinct pattern in the cosmic microwave background. Gravitational waves have a "handedness," much like light waves, and can have left- and right-handed polarizations.
"The swirly B-mode 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 co-leader Chao-Lin Kuo (Stanford/SLAC).
The team examined spatial scales on the sky spanning about one to five degrees (two to ten times the width of the full Moon). To do this, they traveled to the South Pole to take advantage of its cold, dry, stable air.
"The South Pole is the closest you can get to space and still be on the ground," said Kovac. "It's one of the driest and clearest locations on Earth, perfect for observing the faint microwaves from the Big Bang."
They were surprised to detect a B-mode polarization signal considerably stronger than many cosmologists expected. The team analyzed their data for more than three years in an effort to rule out any errors. They also considered whether dust in our galaxy could produce the observed pattern, but the data suggest this is highly unlikely.
"This has been like looking for a needle in a haystack, but instead we found a crowbar," said co-leader Clem Pryke (University of Minnesota).
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Gravitational waves from inflation generate a faint but distinctive twisting pattern in the polarization of the CMB, known as a "curl" or B-mode pattern. For the density fluctuations that generate most of the polarization of the CMB, this part of the primordial pattern is exactly zero. Shown here is the actual B-mode pattern observed with the BICEP2 telescope, with the line segments showing the polarization from different spots on the sky. The red and blue shading shows the degree of clockwise and anti-clockwise twisting of this B-mode pattern.
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UPDATE - Wired - The team at the Harvard-Smithsonian Center for Astrophysics has announced they've found "The First Direct Evidence of Cosmic Inflation." The scientists say that after three years of research and staring at a patch of sky, they have found and observed waves (signals of light) that are the "smoking gun" of cosmic inflation and echoes of the Big Bang theory.
The scientists have data that represents the first images of gravitational waves, or ripples in space-time. In the plainest English possible: these waves have been described as the "first tremors of the Big Bang" and were created fractions of a second after our universe came to be. They were part of Albert Einstein's General Theory of relativity, but have never been seen.
Since the cosmic microwave background is a form of light, it exhibits all the properties of light, including polarization. On Earth, sunlight is scattered by the atmosphere and becomes polarized, which is why polarized sunglasses help reduce glare. In space, the cosmic microwave background was scattered by atoms and electrons and became polarized too.
"Our team hunted for a special type of polarization called 'B-modes,' which represents a twisting or 'curl' pattern in the polarized orientations of the ancient light," said co-leader Jamie Bock (Caltech/JPL).
Gravitational waves squeeze space as they travel, and this squeezing produces a distinct pattern in the cosmic microwave background. Gravitational waves have a "handedness," much like light waves, and can have left- and right-handed polarizations.
"The swirly B-mode 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 co-leader Chao-Lin Kuo (Stanford/SLAC).
The team examined spatial scales on the sky spanning about one to five degrees (two to ten times the width of the full Moon). To do this, they traveled to the South Pole to take advantage of its cold, dry, stable air.
"The South Pole is the closest you can get to space and still be on the ground," said Kovac. "It's one of the driest and clearest locations on Earth, perfect for observing the faint microwaves from the Big Bang."
They were surprised to detect a B-mode polarization signal considerably stronger than many cosmologists expected. The team analyzed their data for more than three years in an effort to rule out any errors. They also considered whether dust in our galaxy could produce the observed pattern, but the data suggest this is highly unlikely.
"This has been like looking for a needle in a haystack, but instead we found a crowbar," said co-leader Clem Pryke (University of Minnesota).
Read more »
