scholarly journals Status of the GroundBIRD Telescope

2018 ◽  
Vol 168 ◽  
pp. 01014
Author(s):  
J. Choi ◽  
R. Génova-Santos ◽  
M. Hattori ◽  
M. Hazumi ◽  
H. Ishitsuka ◽  
...  
Keyword(s):  
Cosmic Microwave Background ◽  
Early Universe ◽  
Present Status ◽  
Big Bang ◽  
Inflationary Cosmology ◽  
Polarization Pattern ◽  
Microwave Background ◽  
Systematic Effects ◽  
The Big Bang

Our understanding of physics at very early Universe, as early as 10−35 s after the Big Bang, relies on the scenario known as the inflationary cosmology. Inflation predicts a particular polarization pattern in the cosmic microwave background, known as the B-mode yet the strength of such polarization pattern is extremely weak. To search for the B-mode of the polarization in the cosmic microwave background, we are constructing an off-axis rotating telescope to mitigate systematic effects as well as to maximize the sky coverage of the observation. We will discuss the present status of the GroundBIRD telescope.

The Cosmic Microwave Background

2020 ◽  
pp. 272-289
Author(s):  
Hui Chieh Teoh
Keyword(s):  
Cosmic Microwave Background ◽  
Early Universe ◽  
Large Scale ◽  
Big Bang ◽  
Space Missions ◽  
Expanding Universe ◽  
Microwave Background ◽  
The Big Bang ◽  
The Universe

The cosmic microwave background (CMB) holds many secrets of the origin and the evolution of our universe. This ancient radiation was created shortly after the Big Bang, when the expanding universe cooled and became transparent, sending an afterglow of light in all directions. It is a pattern frozen in place that dates back to 375,000 years after the birth of the universe. Numerous experiments and space missions have made increasingly higher resolution maps of the CMB radiation, with the aims to learn more about the conditions of our early universe and the origin of stars, galaxies, and the large-scale cosmic structures that populate our universe today.

scholarly journals INFLATION, QUANTUM FIELDS, AND CMB ANISOTROPIES

2009 ◽  
Vol 18 (14) ◽  
pp. 2329-2335 ◽  
Author(s):  
IVÁN AGULLÓ ◽  
JOSÉ NAVARRO-SALAS ◽  
GONZALO J. OLMO ◽  
LEONARD PARKER
Keyword(s):  
Cosmic Microwave Background ◽  
Gravitational Waves ◽  
Early Universe ◽  
Inflationary Cosmology ◽  
Quantum Field ◽  
Quantum Fields ◽  
Microwave Background ◽  
Cosmological Inflation ◽  
Near Future ◽  
Field Renormalization

Inflationary cosmology has proven to be the most successful at predicting the properties of the anisotropies observed in the cosmic microwave background (CMB). In this essay we show that quantum field renormalization significantly influences the generation of primordial perturbations and hence the expected measurable imprint of cosmological inflation on the CMB. However, the new predictions remain in agreement with observation, and in fact favor the simplest forms of inflation. In the near future, observations of the influence of gravitational waves from the early universe on the CMB will test our new predictions.

The Battle for the Cosmos!

2019 ◽  
pp. 84-92
Author(s):  
Nicholas Mee
Keyword(s):  
Steady State ◽  
Cosmic Microwave Background ◽  
Big Bang ◽  
State Theory ◽  
Microwave Background ◽  
George Gamow ◽  
Big Bang Theory ◽  
Fred Hoyle ◽  
The Big Bang ◽  
The Universe

We now know the universe began with the Big Bang 13.8 billion years ago, but for several years debate raged between the supporters of the Big Bang theory led by George Gamow and supporters of the Steady State theory led by Fred Hoyle. Hoyle showed that the elements were synthesized in the stars, not in the Big Bang as Gamow believed. But Gamow’s colleagues Alpher and Herman predicted the existence of the cosmic microwave background (CMB) created immediately after the Big Bang. The CMB was discovered by Penzias and Wilson and this provided the crucial evidence that the Big Bang theory is correct. The CMB has since been studied in detail by a series of space probes.

scholarly journals Does standard cosmology really predict the cosmic microwave background?

F1000Research ◽  
2020 ◽  
Vol 9 ◽  
pp. 261
Author(s):  
Hartmut Traunmüller
Keyword(s):  
Cosmic Microwave Background ◽  
Boundary Surface ◽  
Big Bang ◽  
Microwave Background ◽  
Initial State ◽  
Standard Cosmology ◽  
Return Path ◽  
The Right ◽  
The Big Bang ◽  
The Universe

In standard Big Bang cosmology, the universe expanded from a very dense, hot and opaque initial state. The light that was last scattered about 380,000 years later, when the universe had become transparent, has been redshifted and is now seen as thermal radiation with a temperature of 2.7 K, the cosmic microwave background (CMB). However, since light escapes faster than matter can move, it is prudent to ask how we, made of matter from this very source, can still see the light. In order for this to be possible, the light must take a return path of the right length. A curved return path is possible in spatially closed, balloon-like models, but in standard cosmology, the universe is “flat” rather than balloon-like, and it lacks a boundary surface that might function as a reflector. Under these premises, radiation that once filled the universe homogeneously cannot do so permanently after expansion, and we cannot see the last scattering event. It is shown that the traditional calculation of the CMB temperature is inappropriate and that light emitted by any source inside the Big Bang universe earlier than half its “conformal age” can only become visible to us via a return path. Although often advanced as the best evidence for a hot Big Bang, the CMB actually tells against a formerly smaller universe and so do also distant galaxies.

scholarly journals Does standard cosmology really predict the cosmic microwave background?

F1000Research ◽  
2021 ◽  
Vol 9 ◽  
pp. 261
Author(s):  
Hartmut Traunmüller
Keyword(s):  
Cosmic Microwave Background ◽  
Boundary Surface ◽  
Big Bang ◽  
Microwave Background ◽  
Initial State ◽  
Standard Cosmology ◽  
Return Path ◽  
The Right ◽  
The Big Bang ◽  
The Universe

In standard Big Bang cosmology, the universe expanded from a very dense, hot and opaque initial state. The light that was last scattered about 380,000 years later, when the universe had become transparent, has been redshifted and is now seen as thermal radiation with a temperature of 2.7 K, the cosmic microwave background (CMB). However, since light escapes faster than matter can move, it is prudent to ask how we, made of matter from this very source, can still see the light. In order for this to be possible, the light must take a return path of the right length. A curved return path is possible in spatially closed, balloon-like models, but in standard cosmology, the universe is “flat” rather than balloon-like, and it lacks a boundary surface that might function as a reflector. Under these premises, radiation that once filled the universe homogeneously cannot do so permanently after expansion, and we cannot see the last scattering event. It is shown that the traditional calculation of the CMB temperature is inappropriate and that light emitted by any source inside the Big Bang universe earlier than half its “conformal age” can only become visible to us via a return path. Although often advanced as the best evidence for a hot Big Bang, the CMB actually tells against a formerly smaller universe and so do also distant galaxies.

scholarly journals Does standard cosmology really predict the cosmic microwave background?

F1000Research ◽  
2021 ◽  
Vol 9 ◽  
pp. 261
Author(s):  
Hartmut Traunmüller
Keyword(s):  
Cosmic Microwave Background ◽  
Boundary Surface ◽  
Big Bang ◽  
Microwave Background ◽  
Initial State ◽  
Standard Cosmology ◽  
Return Path ◽  
The Right ◽  
The Big Bang ◽  
The Universe

In standard Big Bang cosmology, the universe expanded from a very dense, hot and opaque initial state. The light that was last scattered about 380,000 years later, when the universe had become transparent, has been redshifted and is now seen as thermal radiation with a temperature of 2.7 K, the cosmic microwave background (CMB). However, since light escapes faster than matter can move, it is prudent to ask how we, made of matter from this very source, can still see the light. In order for this to be possible, the light must take a return path of the right length. A curved return path is possible in spatially closed, balloon-like models, but in standard cosmology, the universe is “flat” rather than balloon-like, and it lacks a boundary surface that might function as a reflector. Under these premises, radiation that once filled the universe homogeneously cannot do so permanently after expansion, and we cannot see the last scattering event. It is shown that the traditional calculation of the CMB temperature is inappropriate and that light emitted by any source inside the Big Bang universe earlier than half its “conformal age” can only become visible to us via a return path. Although often advanced as the best evidence for a hot Big Bang, the CMB actually tells against a formerly smaller universe and so do also distant galaxies.

scholarly journals Antarctic observations of the cosmic microwave background

1992 ◽  
Vol 9 ◽  
pp. 589-589
Author(s):  
George F Smoot
Keyword(s):  
Cosmic Microwave Background ◽  
Elevation Angle ◽  
Precipitable Water ◽  
High Elevation ◽  
Big Bang ◽  
Atmospheric Emission ◽  
Microwave Background ◽  
Galactic Emission ◽  
The Big Bang ◽  
The Antarctic

In the standard cosmology of the Big Bang theory the cosmic microwave background (CMB) is the remnant radiation from the hot early universe. The sky signal is comprised of radiation from the CMB, from Galactic emission, from atmospheric emission, and from instrument sidelobes seeing the ground and man-made interference. One observes in directions of minimum galactic signal. The antarctic polar plateau provides the best site in the world for low atmospheric emission, low horizons, low man-made interference, and reasonable accessibility. The low column density of precipitable water and extreme stability for periods exceeding a week, combined with low RFI are critical. A very important secondary benefit for anisotropy experiments is the ability to observe the same part of the sky continuously at a high elevation angle.

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