Physicists Find New Way of Exploring Cosmic Microwave Background

Skype April 25, 2018 Physics Leave a comment 457 Views

A team of Canadian physicists has developed a new way to improve our knowledge of the Big Bang by measuring radiation from its afterglow, called the cosmic microwave background radiation. The team’s results, published in the journal Foundations of Physics, predict the maximum bandwidth of the Universe, which is the maximum speed at which any change can occur in the Universe.

$A visualization of the polarization of the CMB, as detected by Planck. The CMB is a snapshot of the oldest light in our Universe, imprinted on the sky when the Universe was just 380,000 years old. It shows tiny temperature fluctuations that correspond to regions of slightly different densities, representing the seeds of all future structure: the stars and galaxies of today. A small fraction of the CMB is polarized – it vibrates in a preferred direction. This is a result of the last encounter of this light with electrons, just before starting its cosmic journey. For this reason, the polarization of the CMB retains information about the distribution of matter in the early Universe, and its pattern on the sky follows that of the tiny fluctuations observed in the temperature of the CMB. In these images, the color scale represents temperature differences in the CMB, while the texture indicates the direction of the polarized light. The patterns seen in the texture are characteristic of E-mode polarization, which is the dominant type for the CMB. The large oval shows the CMB polarization as seen by Planck on the entire sky. For the sake of illustration, both data sets have been filtered to show mostly the signal detected on scales around 5° on the sky. However, fluctuations in both the CMB temperature and polarization are present and were observed by Planck also on larger as well as smaller angular scales. To provide a taste of the fine structure of the measurement obtained by Planck, a zoomed-in view on a smaller patch of the sky, measuring 20° across, is also provided on the left. This is first shown with the same filtering as the all-sky image (upper frame), then with a different filter that shows mostly the signal detected on angles on the sky of about 20 arcminutes (lower frame). Image credit: ESA / Planck Collaboration.$

A visualization of the polarization of the CMB, as detected by Planck. The CMB is a snapshot of the oldest light in our Universe, imprinted on the sky when the Universe was just 380,000 years old. It shows tiny temperature fluctuations that correspond to regions of slightly different densities, representing the seeds of all future structure: the stars and galaxies of today. A small fraction of the CMB is polarized – it vibrates in a preferred direction. This is a result of the last encounter of this light with electrons, just before starting its cosmic journey. For this reason, the polarization of the CMB retains information about the distribution of matter in the early Universe, and its pattern on the sky follows that of the tiny fluctuations observed in the temperature of the CMB. In these images, the color scale represents temperature differences in the CMB, while the texture indicates the direction of the polarized light. The patterns seen in the texture are characteristic of E-mode polarization, which is the dominant type for the CMB. The large oval shows the CMB polarization as seen by Planck on the entire sky. For the sake of illustration, both data sets have been filtered to show mostly the signal detected on scales around 5° on the sky. However, fluctuations in both the CMB temperature and polarization are present and were observed by Planck also on larger as well as smaller angular scales. To provide a taste of the fine structure of the measurement obtained by Planck, a zoomed-in view on a smaller patch of the sky, measuring 20° across, is also provided on the left. This is first shown with the same filtering as the all-sky image (upper frame), then with a different filter that shows mostly the signal detected on angles on the sky of about 20 arcminutes (lower frame). Image credit: ESA / Planck Collaboration.

The cosmic microwave background is a reverberation or afterglow left from when the Universe was about 300,000 years old.

It was first discovered in 1964 as a ubiquitous faint noise in radio antennas.

In the past two decades, space-based telescopes like ESA’s Planck satellite have started to measure it with great accuracy, revolutionizing our understanding of the Big Bang.

Professor Achim Kempf from the University of Waterloo, Canada, led the work to develop the new calculation, jointly with Aidan Chatwin-Davies and Robert Martin.

“It’s like video on the Internet,” Professor Kempf said.

“If you can measure the cosmic microwave background with very high resolution, this can tell you about the bandwidth of the Universe, in a similar way to how the sharpness of the video image on your Skype call tells you about the bandwidth of your internet connection.”

“Teams of astronomers are currently working on even more accurate measurements of the cosmic microwave background,” the researchers said.

“By using the new calculations, these upcoming measurements might reveal the value of the Universe’s fundamental bandwidth, thereby telling us also about the fastest thing that ever happened, the Big Bang.”

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Achim Kempf. Quantum Gravity, Information Theory and the CMB. Foundations of Physics, published online April 5, 2018; doi: 10.1007/s10701-018-0163-2