scholarly journals Emergent universe revisited through the CSL theory

2021 ◽  
Vol 81 (12) ◽  
Author(s):  
Gabriel R. Bengochea ◽  
María Pía Piccirilli ◽  
Gabriel León
Keyword(s):  
Characteristic Feature ◽  
The Other ◽  
Emergent Universe ◽  
Slow Roll ◽  
Other Hand ◽  
Classical Transition ◽  
Spontaneous Localization ◽  
Continuous Spontaneous Localization ◽  
Scalar Perturbations ◽  
Slow Roll Inflation

AbstractIn this work we analyze how the spectrum of primordial scalar perturbations is modified, within the emergent universe scenario, when a particular version of the Continuous Spontaneous Localization (CSL) model is incorporated as the generating mechanism of initial perturbations, providing also an explanation to the quantum-to-classical transition of such perturbations. On the other hand, a phase of super-inflation, prior to slow-roll inflation, is a characteristic feature of the emergent universe hypothesis. In recent works, it was shown that the super-inflation phase could generically induce a suppression of the temperature anisotropies of the CMB at large angular scales. We study here under what conditions the CSL maintains or modifies these characteristics of the emergent universe and their compatibility with the CMB observations.

scholarly journals Scalar perturbations during multiple-field slow-roll inflation

2002 ◽  
Vol 19 (4) ◽  
pp. 613-640 ◽  
Author(s):  
S Groot Nibbelink ◽  
B J W van Tent
Keyword(s):  
Slow Roll ◽  
Multiple Field ◽  
Scalar Perturbations ◽  
Slow Roll Inflation

scholarly journals Origin of the Galactic Diffuse X-ray Emission: Iron K-Shell Line Diagnostics

2016 ◽  
Vol 11 (S322) ◽  
pp. 206-207
Author(s):  
Masayoshi Nobukawa ◽  
Hideki Uchiyama ◽  
Kumiko K. Nobukawa ◽  
Shigeo Yamauchi ◽  
Katsuji Koyama
Keyword(s):  
Characteristic Feature ◽  
Galactic Plane ◽  
Cataclysmic Variables ◽  
Point Sources ◽  
The Other ◽  
X Ray ◽  
Other Hand ◽  
Spectral Models ◽  
Archive Data

AbstractAn unresolved X-ray emission extends along the Galactic plane, so-called the Galactic diffuse X-ray emission (GDXE). The characteristic feature is three K-shell lines of Fe at 6.4, 6.7, and 6.9 keV. Recently, superposition of faint point sources, such as Cataclysmic variables (CVs) and Active binaries (ABs) is thought to be a major origin, although it is under debate which sub-class mostly contribute. We re-analyzed the Suzaku archive data and constructed spectral models of ABs, magnetic CVs (mCVs), and non-magnetic CVs (non-mCVs). The GBXE is explained by combination of those models; non-mCVs and ABs mainly contribute while mCVs account for ~10% or less of the 5–10 keV flux. On the other hand, the GCXE and GRXE spectra cannot be represented by any combination of the point sources, indicating another origin would be required.

scholarly journals Methodology of Problems Creation and Selection for Astronomy Olympiads on Example of Tasks on the Topic of Kepler's Laws

2020 ◽  
Vol 7 (1) ◽  
pp. 156-165
Author(s):  
Yaroslav Ersteniuk ◽  
Ivan Gasyuk ◽  
Anna Boryschak ◽  
Petro Yakubovskyi
Keyword(s):  
Characteristic Feature ◽  
Intellectual Development ◽  
The Other ◽  
The Third ◽  
The Past ◽  
Regional Stage ◽  
Detailed Explanation ◽  
Other Hand ◽  
Third Stage ◽  
Selection For

Based on many years of experience in the organization of the third stage of Ukrainian National Astronomy Olympiad, the authors of the article attempt to formulate general principles for the selection and compilation of astronomy olympiad problems, as well as to demonstrate the application of the described principles on the example of astronomy olympiads in Ivano-Frankivsk region. The peculiarities of school Olympiad in astronomy, the purpose of their conduct, the specificity of task packages, including necessity for differentiation by complexity and topics, were analyzed. A characteristic feature of the Olympiad tasks is their non-standard nature, necessity to use methods that are unusual for students to solve problems. On the other hand, such tasks should match intellectual development of the competition participants, and the course of the solution should be accessible to understanding and should not require knowledge of a university program. In particular, on the basis of the analysis by the authors of the process of compiling astronomy Olympiad tasks, which were offered to students in the past years at the regional stage of the student Olympiads, were identified, the methods of their creation were systematized and characterized. Each method contains a detailed explanation, justification for its use and examples, both analytical and practical. For the sake of clarity, the topic “Kepler Laws” was choosen for Olympiad problems, which were analyzed and methods used to create them were described. This topic is one of the fundamental in the schoolar astronomy, which determines both the need to include such tasks in the Olympiad program and the complexity of their choice, and creation, because the topic is narrow enough and is qualitatively covered in various textbooks and collections of problems.

scholarly journals MARX ET CO REVISITED. REPRESENTATIONS OF THE ECONOMY IN RALF ANDTBACKA’S WUNDERKAMMER (2008)

2020 ◽  
Vol 29 (60) ◽  
pp. 72-91
Author(s):  
Kristina Malmio
Keyword(s):  
Characteristic Feature ◽  
Present Article ◽  
Cognitive Mapping ◽  
Karl Marx ◽  
Human Subjects ◽  
Economic Transformation ◽  
The Other ◽  
Other Hand ◽  
The One

The present article studies the representation of economy in Wunderkammer (2008), a collection of poetry by Finland-Swedish author Ralf Andtbacka. Going back to the historical form of cabinets of curiosities, Wunderkammer depicts acts of buying, selling, and collecting. By showing the connectivity of objects and their impact on human subjects, Andtbacka actualizes and deconstructs topics originally initiated by Karl Marx, such as value, fetish, commodifica-tion, and alienation. The portrayal of capitalism, both past and pres-ent, in the book is highly ambivalent. On the one hand, collecting functions as a critical, anticapitalistic act. On the other hand, eco-nomic discourse has invaded the text and turned the author into a writing machine powered by the energy of neoliberal labor. Besides an excess of objects, the poems display an overflow of information, a characteristic feature of a postcapitalist economy. As an exam-ple of cognitive mapping, Wunderkammer allegorically portrays humans, objects, and information in the middle of a paradoxical economic transformation.

A study of cometary eruptions through OH radio-lines

1999 ◽  
Vol 173 ◽  
pp. 249-254
Author(s):  
A.M. Silva ◽  
R.D. Miró
Keyword(s):  
Short Duration ◽  
Growth Curves ◽  
The Other ◽  
Initial Mass ◽  
Radio Lines ◽  
Other Hand ◽  
Sudden Rise

AbstractWe have developed a model for theH2OandOHevolution in a comet outburst, assuming that together with the gas, a distribution of icy grains is ejected. With an initial mass of icy grains of 108kg released, theH2OandOHproductions are increased up to a factor two, and the growth curves change drastically in the first two days. The model is applied to eruptions detected in theOHradio monitorings and fits well with the slow variations in the flux. On the other hand, several events of short duration appear, consisting of a sudden rise ofOHflux, followed by a sudden decay on the second day. These apparent short bursts are frequently found as precursors of a more durable eruption. We suggest that both of them are part of a unique eruption, and that the sudden decay is due to collisions that de-excite theOHmaser, when it reaches the Cometopause region located at 1.35 × 105kmfrom the nucleus.

Closing the GAP—A 5Å Scanning Microscope

1969 ◽  
Vol 27 ◽  
pp. 6-7
Author(s):  
A. V. Crewe
Keyword(s):  
Normal Form ◽  
The Other ◽  
Resolving Power ◽  
Scanning Microscope ◽  
Conventional Microscope ◽  
Other Hand ◽  
Closing The Gap ◽  
Thermal Sources ◽  
Better Than ◽  
Transmission Microscope

We have become accustomed to differentiating between the scanning microscope and the conventional transmission microscope according to the resolving power which the two instruments offer. The conventional microscope is capable of a point resolution of a few angstroms and line resolutions of periodic objects of about 1Å. On the other hand, the scanning microscope, in its normal form, is not ordinarily capable of a point resolution better than 100Å. Upon examining reasons for the 100Å limitation, it becomes clear that this is based more on tradition than reason, and in particular, it is a condition imposed upon the microscope by adherence to thermal sources of electrons.

Life Beyond 1MeV

1980 ◽  
Vol 38 ◽  
pp. 30-33
Author(s):  
K.H. Westmacott
Keyword(s):  
Electron Microscopy ◽  
Past Experience ◽  
The Other ◽  
Good Case ◽  
Other Hand ◽  
The U.S

Life beyond 1MeV – like life after 40 – is not too different unless one takes advantage of past experience and is receptive to new opportunities. At first glance, the returns on performing electron microscopy at voltages greater than 1MeV diminish rather rapidly as the curves which describe the well-known advantages of HVEM often tend towards saturation. However, in a country with a significant HVEM capability, a good case can be made for investing in instruments with a range of maximum accelerating voltages. In this regard, the 1.5MeV KRATOS HVEM being installed in Berkeley will complement the other 650KeV, 1MeV, and 1.2MeV instruments currently operating in the U.S. One other consideration suggests that 1.5MeV is an optimum voltage machine – Its additional advantages may be purchased for not much more than a 1MeV instrument. On the other hand, the 3MeV HVEM's which seem to be operated at 2MeV maximum, are much more expensive.

Sign in / Sign up

Export Citation Format

Share Document