Posts Tagged ‘cosmic microwave background’
How to encrypt a message in the afterglow of the big bang
If you’ve got a secret to keep safe, look to the skies. Physicists have proposed using the afterglow of the big bang to make encryption keys.
The security of many encryption methods relies on generating large random numbers to act as keys to encrypt or decipher information. Computers can spawn these keys with certain algorithms, but they aren’t truly random, so another computer armed with the same algorithm could potentially duplicate the key.
An alternative is to rely on physical randomness, like the thermal noise on a chip or the timing of a user’s keystrokes.
Now Jeffrey Lee and Gerald Cleaver at Baylor University in Waco, Texas, have taken that to the ultimate extreme by looking at the cosmic microwave background (CMB), the thermal radiation left over from the big bang. Read the rest of this entry »
How We’ve ‘Morphed’ From “Starry Night” to Planck’s View of the BICEP2 Field
Read more at www.universetoday.com
Planck: Gravitational waves remain elusive
Despite earlier reports of a possible detection, a joint analysis of data from ESA’s Planck satellite and the ground-based BICEP2 and Keck Array experiments has found no conclusive evidence of primordial gravitational waves.
The Universe began about 13.8 billion years ago and evolved from an extremely hot, dense and uniform state to the rich and complex cosmos of galaxies, stars and planets we see today.
An extraordinary source of information about the Universe’s history is the Cosmic Microwave Background, or CMB, the legacy of light emitted only 380 000 years after the Big Bang.
ESA’s Planck satellite observed this background across the whole sky with unprecedented accuracy, and a broad variety of new findings about the early Universe has already been revealed over the past two years. Read the rest of this entry »
Physics of the cosmic microwave background anisotropy
Martin Bucher
Observations of the cosmic microwave background (CMB), especially of its frequency spectrum and its anisotropies, both in temperature and in polarization, have played a key role in the development of modern cosmology and our understanding of the very early universe.
We review the underlying physics of the CMB and how the primordial temperature and polarization anisotropies were imprinted.
Possibilities for distinguishing competing cosmological models are emphasized.
The current status of CMB experiments and experimental techniques with an emphasis toward future observations, particularly in polarization, is reviewed.
The physics of foreground emissions, especially of polarized dust, is discussed in detail, since this area is likely to become crucial for measurements of the B modes of the CMB polarization at ever greater sensitivity….
… Read more at http://arxiv.org/pdf/1501.04288v1.pdf
POLARBEAR seeks cosmic answers in microwave polarization
![The Huan Tran Telescope in the Atacama Desert of Chile. The POLARBEAR microwave bolometers are mounted on the telescope to study the polarization of light from a period 380,000 years after the Big Bang. Credit: POLARBEAR consortium](https://physicsforme.wordpress.com/wp-content/uploads/2014/10/polarbearsee.jpg?w=700)
The Huan Tran Telescope in the Atacama Desert of Chile. The POLARBEAR microwave bolometers are mounted on the telescope to study the polarization of light from a period 380,000 years after the Big Bang. Credit: POLARBEAR consortium
An international team of physicists has measured a subtle characteristic in the polarization of the cosmic microwave background radiation that will allow them to map the large-scale structure of the universe, determine the masses of neutrinos and perhaps uncover some of the mysteries of dark matter and dark energy. Read the rest of this entry »
Rumours swirl over credibility of big bang ripple find
Has the recent discovery of gravitational waves been reduced to dust? Not so fast.
The news that ripples in space-time, called gravitational waves, had been spotted stunned the physics community earlier this year. This week, rumours began swirling that the scientists who reported the find have now admitted to making a mistake. The team missed a key detail in its analysis of galactic dust, the rumours suggest, making it more likely that the signal came from a source other than gravitational waves.
But the team’s response to this claim is unequivocal: “We’ve done no such thing,” says principal investigator John Kovac at Harvard University. The validity of the discovery won’t be known until another group either supports or opposes their finding, which could happen later this year.
In March, the BICEP2 collaboration announced that it had seen an imprint on ancient cosmic light that it says was created by gravitational waves. Those waves are thought to be products of inflation, a period of rapid growth during the first sliver of a second after the big bang. The finding was hailed as a smoking gun for the theory of inflation – and as evidence that theories of a multiverse may be true. Read the rest of this entry »