scholarly journals Evolution of cosmological perturbations and the production of non-Gaussianities through a nonsingular bounce: Indications for a no-go theorem in single field matter bounce cosmologies

2015 ◽  
Vol 92 (6) ◽  
Author(s):  
Jerome Quintin ◽  
Zeinab Sherkatghanad ◽  
Yi-Fu Cai ◽  
Robert H. Brandenberger
Keyword(s):  
Cosmological Perturbations ◽  
Single Field

G-INFLATION: INFLATION WITH THE MOST GENERAL SECOND-ORDER FIELD EQUATIONS

2012 ◽  
Vol 10 ◽  
pp. 77-84
Author(s):  
TSUTOMU KOBAYASHI ◽  
MASAHIDE YAMAGUCHI ◽  
JUN'ICHI YOKOYAMA
Keyword(s):  
Power Spectra ◽  
Second Order ◽  
Stability Criteria ◽  
Cosmological Perturbations ◽  
Field Equations ◽  
Special Cases ◽  
Single Field ◽  
The Stability

In this talk, we have discussed generalized Galileons as a framework to develop the most general single-field inflation models ever, (Generalized) G-inflation, containing previous examples such as k-inflation, extended inflation, and new Higgs inflation as special cases. We have also investigated the background and perturbation evolution in this model, calculating the most general quadratic actions for tensor and scalar cosmological perturbations to give the stability criteria and the power spectra of primordial fluctuations.

Experiments in Bright-Field Imaging with Hollow-Cone Illumination

1981 ◽  
Vol 39 ◽  
pp. 226-227
Author(s):  
W. Kunath ◽  
K. Weiss ◽  
E. Zeitler
Keyword(s):  
Signal To Noise Ratio ◽  
Carbon Support ◽  
Electronic System ◽  
Optic Axis ◽  
Hollow Cone ◽  
Signal To Noise ◽  
Bright Field ◽  
Noise Ratio ◽  
Single Field ◽  
Field Imaging

Bright-field images taken with axial illumination show spurious high contrast patterns which obscure details smaller than 15 ° Hollow-cone illumination (HCI), however, reduces this disturbing granulation by statistical superposition and thus improves the signal-to-noise ratio. In this presentation we report on experiments aimed at selecting the proper amount of tilt and defocus for improvement of the signal-to-noise ratio by means of direct observation of the electron images on a TV monitor.Hollow-cone illumination is implemented in our microscope (single field condenser objective, Cs = .5 mm) by an electronic system which rotates the tilted beam about the optic axis. At low rates of revolution (one turn per second or so) a circular motion of the usual granulation in the image of a carbon support film can be observed on the TV monitor. The size of the granular structures and the radius of their orbits depend on both the conical tilt and defocus.

Connecting Gospels

2018 ◽  
Keyword(s):  
Second Century ◽  
Common Belief ◽  
Field Of Study ◽  
Early Christian ◽  
Single Field ◽  
Vantage Points ◽  
Canonical Texts ◽  
Normative Status ◽  
Two Bodies ◽  
Shed Light

By the late second century, early Christian gospels had been divided into two groups by a canonical boundary that assigned normative status to four of them while consigning their competitors to the margins. The project of this volume is to find ways to reconnect these divided texts. The primary aim is not to address the question whether the canonical/non-canonical distinction reflects substantive and objectively verifiable differences between the two bodies of texts—although that issue may arise at various points. Starting from the assumption that, in spite of their differences, all early gospels express a common belief in the absolute significance of Jesus and his earthly career, the intention is to make their interconnectedness fruitful for interpretation. The approach taken is thematic and comparative: a selected theme or topic is traced across two or more gospels on either side of the canonical boundary, and the resulting convergences and divergences shed light not least on the canonical texts themselves as they are read from new and unfamiliar vantage points. The outcome is to demonstrate that early gospel literature can be regarded as a single field of study, in contrast to the overwhelming predominance of the canonical four characteristic of traditional gospels scholarship.

Variation in Soybean Aphid (Hemiptera: Aphididae) Biotypes Within Fields

2021 ◽  
Author(s):  
S J Bhusal ◽  
R L Koch ◽  
A J Lorenz
Keyword(s):  
Resistance Genes ◽  
Environmental Sustainability ◽  
Soybean Aphid ◽  
Aphis Glycines ◽  
Aphid Resistance ◽  
Soybean Cultivars ◽  
Major Pest ◽  
Single Field ◽  
Aphis Glycines Matsumura ◽  
Multiple Resistance Genes

Abstract Soybean aphid (Aphis glycines Matsumura (Hemiptera: Aphididae)) has been a major pest of soybean in North America since its detection in this continent in 2000 and subsequent spread. Although several aphid resistance genes have been identified, at least four soybean aphid biotypes have been discovered, with three of them being virulent on soybean cultivars with certain soybean aphid resistance genes. These biotypes are known to vary across years and locations, but information on their variation within single fields is limited. An investigation was conducted to study the variation of soybean aphid biotypes within single townships and fields in Minnesota. Screening of 28 soybean aphid isolates collected from seven soybean fields (six soybean fields in Cairo and Wellington Townships of Renville County, MN and one field in Wilmar Township of Kandiyohi County, MN) revealed the existence of multiple known biotypes of soybean aphid within single fields of soybean. We found up to three biotypes of soybean aphid in a single field. Two biotypes were found in five fields while only one field had only a single biotype. Three isolates presented reactions on a panel of resistant and susceptible indicator lines that were different from known biotypes. These results highlight the importance of characterizing soybean aphid biotypes in small geographical areas and utilizing generated knowledge to develop soybean cultivars pyramided with multiple resistance genes. The outcome will be decreased use of insecticides, thereby improving economic and environmental sustainability of soybean production.

scholarly journals Cosmological perturbations in Gauss-Bonnet quasi-dilaton massive gravity

2021 ◽  
Vol 103 (12) ◽  
Author(s):  
Amin Rezaei Akbarieh ◽  
Sobhan Kazempour ◽  
Lijing Shao
Keyword(s):  
Massive Gravity ◽  
Cosmological Perturbations
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