scholarly journals Cosmic Microwave Background Fluctuation Searches On 5° to 10° Scales

1990 ◽  
Vol 139 ◽  
pp. 398-399
Author(s):  
R. D. Davies ◽  
R. A. Watson ◽  
R. Rebolo ◽  
J. Beckman ◽  
A. N. Lasenby
Keyword(s):  
Cosmic Microwave Background ◽  
Early Universe ◽  
Galaxy Formation ◽  
Atmospheric Effects ◽  
Microwave Background ◽  
Fundamental Information ◽  
Background Fluctuation ◽  
Beam Technique

Deep observations of the cosmic microwave background (CMB) have been made at 10 GHz with beamwidths of 5° and 8° using a triple-beam technique, which greatly reduces atmospheric effects. Significant signals are detected with an rms of ΔT/T ~ 4×10−5. These signals could be intrinsic to the CMB and are providing fundamental information about galaxy formation in the early universe. A component of this 10 GHz emission may be coming from galactic synchrotron features. This galactic contribution will be elucidated in forthcoming 15 and 30 GHz observations.

scholarly journals Deep 10 and 15 GHZ Searches for CMB Anisotropies

1992 ◽  
Vol 9 ◽  
pp. 323-325
Author(s):  
R. D. Davies ◽  
A. N. Lasenby
Keyword(s):  
Dark Matter ◽  
Cosmic Microwave Background ◽  
Early Universe ◽  
Galaxy Formation ◽  
Cold Dark Matter ◽  
Galactic Structure ◽  
Observational Cosmology ◽  
Significant Progress ◽  
Microwave Background ◽  
Observing Systems

The search for anisotropies in the Cosmic Microwave Background (CMB) is fundamental to observational cosmology: it requires observations on a range of angular scales and at a range of frequencies to distinguish CMB structure from foreground galactic structure. We have made significant progress in setting new limits to CMB anisotropies on angular scales of 3°-12° using scaled observing systems at 10 and 15 GHz. This regime of angular scales is particularly matched to the predictions of Cold Dark Matter (CDM) and isocurvature scenarios of galaxy formation in the early Universe.

scholarly journals The habitable epoch of the early Universe

2014 ◽  
Vol 13 (4) ◽  
pp. 337-339 ◽  
Author(s):  
Abraham Loeb
Keyword(s):  
Cosmic Microwave Background ◽  
Cosmological Constant ◽  
Water Chemistry ◽  
Early Universe ◽  
Liquid Water ◽  
Matter Density ◽  
Microwave Background ◽  
Star Forming ◽  
Rocky Planets ◽  
The Universe

AbstractIn the redshift range 100≲(1+z)≲137, the cosmic microwave background (CMB) had a temperature of 273–373 K (0–100°C), allowing early rocky planets (if any existed) to have liquid water chemistry on their surface and be habitable, irrespective of their distance from a star. In the standard ΛCDM cosmology, the first star-forming halos within our Hubble volume started collapsing at these redshifts, allowing the chemistry of life to possibly begin when the Universe was merely 10–17 million years old. The possibility of life starting when the average matter density was a million times bigger than it is today is not in agreement with the anthropic explanation for the low value of the cosmological constant.

scholarly journals Implications of the cosmic microwave background power asymmetry for the early universe

2016 ◽  
Vol 93 (12) ◽  
Author(s):  
Christian T. Byrnes ◽  
Donough Regan ◽  
David Seery ◽  
Ewan R. M. Tarrant
Keyword(s):  
Cosmic Microwave Background ◽  
Early Universe ◽  
Microwave Background ◽  
Power Asymmetry

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.

scholarly journals EARLY UNIVERSE SOURCES FOR CMB NON-GAUSSIANITY

2002 ◽  
Vol 17 (29) ◽  
pp. 4273-4280
Author(s):  
ALEJANDRO GANGUI
Keyword(s):  
Power Spectrum ◽  
Cosmic Microwave Background ◽  
Early Universe ◽  
Microwave Background ◽  
Scale Invariant ◽  
Invariant Model ◽  
Primordial Power Spectrum ◽  
Initial States ◽  
Non Gaussian ◽  
Inflationary Models

In the framework of inflationary models with non-vacuum initial states for cosmological perturbations, we study non-Gaussian signatures on the cosmic microwave background (CMB) radiation produced by a broken-scale-invariant model which incorporates a feature at a privileged scale in the primordial power spectrum.

scholarly journals Clustering of hotspots in the cosmic microwave background

2019 ◽  
Vol 206 ◽  
pp. 09017
Author(s):  
En Zuo Joel Low ◽  
Abel Yang
Keyword(s):  
Cosmic Microwave Background ◽  
Galaxy Formation ◽  
Equilibrium Distribution ◽  
Negative Binomial ◽  
Clustering Algorithms ◽  
Quasi Equilibrium ◽  
Microwave Background ◽  
Temperature Maps ◽  
Recombination Epoch ◽  
Frequency Temperature

The physics behind the origin and composition of the Cosmic Microwave Background (CMB) is a well-established topic in the field of Cosmology. Literature on CMB anisotropies reveal consistency with Gaussianity [1], but these were conducted on full multi-frequency temperature maps. In this thesis, we utilise clustering algorithms to specifically conduct statistical analyses on the distribution of hotspots in the CMB. We describe a series of data processing and clustering methodologies conducted, with results that conclusively show that the counts-in-cells distribution of hotspots in the CMB does not follow a Poisson distribution. Rather, the distribution exhibits a much closer fit to both the Negative Binomial Distribution (NBD) and the Gravitational Quasi-Equilibrium Distribution (GQED). From this result, we conclude that structure likely existed in the early universe, from the period of the recombination Epoch, possibly opening new insights in the field of galaxy formation.

scholarly journals Cosmic Strings and Galaxy Formation

1988 ◽  
Vol 130 ◽  
pp. 281-288
Author(s):  
Neil Turok
Keyword(s):  
Early Universe ◽  
Galaxy Formation ◽  
Particle Physics ◽  
Background Radiation ◽  
Big Bang ◽  
High Symmetry ◽  
Particle Spectrum ◽  
Microwave Background ◽  
Hubble Expansion ◽  
Microwave Background Radiation

The hot big bang theory of the early universe is rather well established. Among its successful predictions are the Hubble expansion, the microwave background radiation and the abundances of the light elements. It also fits in rather nicely with ideas from particle physics. According to these ideas (which are firmly based on experiment) at high energies particle interactions become more symmetrical and the apparently complicated particle spectrum today becomes very simple. It is an appealing notion that such a state of high symmetry was actually realised in the very early universe at very high temperatures, and the symmetry was broken as the universe expanded and cooled.

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