scholarly journals Further Remarks on the Cosmological Time Scale

1940 ◽  
Vol 26 (5) ◽  
pp. 332-333 ◽  
Author(s):  
F. Zwicky
Keyword(s):  
2011 ◽  
Vol 20 (10) ◽  
pp. 1969-1973 ◽  
Author(s):  
RAFFAELLA MARGUTTI ◽  
CRISTIANO GUIDORZI ◽  
GUIDO CHINCARINI

We study the variability properties of the prompt emission of Gamma-Ray Bursts in the gamma-ray energy range. We use the power spectrum analysis in the time domain as developed by [Margutti, in preparation]; this technique is suitable to study the rms variations at different time scales. The timing analysis of 252 Swift light-curves in the 15–150 keV energy range reveals the existence of different variability classes. Moreover, after accounting for the cosmological time dilation, the distribution of the GRB characteristic variability time scales is found to cluster around 0.6–1 s we identify this time scale as a characteristic variability time scale of long GRBs in the source rest frame.


2007 ◽  
Vol 16 (05) ◽  
pp. 1529-1539 ◽  
Author(s):  
RYO TAKAHASHI ◽  
MORIMITSU TANIMOTO

We consider a Mass Varying Neutrinos (MaVaNs) model in supersymmetric theory. The model includes effects of supersymmetry breaking transmitted by the gravitational interaction from the hidden sector, in which supersymmetry was broken, to the dark energy sector. Then evolutions of the neutrino mass and the equation of state parameter of the dark energy are presented in the model. It is remarked that only the mass of a sterile neutrino is variable in the case of the vanishing mixing between the left-handed and a sterile neutrino on cosmological time scale. The finite mixing makes the mass of the left-handed neutrino variable.


Philosophies ◽  
2021 ◽  
Vol 6 (4) ◽  
pp. 84
Author(s):  
Susmit Bagchi

The quest to understand the natural and the mathematical as well as philosophical principles of dynamics of life forms are ancient in the human history of science. In ancient times, Pythagoras and Plato, and later, Copernicus and Galileo, correctly observed that the grand book of nature is written in the language of mathematics. Platonism, Aristotelian logism, neo-realism, monadism of Leibniz, Hegelian idealism and others have made efforts to understand reasons of existence of life forms in nature and the underlying principles through the lenses of philosophy and mathematics. In this paper, an approach is made to treat the similar question about nature and existential life forms in view of mathematical philosophy. The approach follows constructivism to formulate an abstract model to understand existential life forms in nature and its dynamics by selectively combining the elements of various schools of thoughts. The formalisms of predicate logic, probabilistic inference and homotopy theory of algebraic topology are employed to construct a structure in local time-scale horizon and in cosmological time-scale horizon. It aims to resolve the relative and apparent conflicts present in various thoughts in the process, and it has made an effort to establish a logically coherent interpretation.


2008 ◽  
Vol 100 (9) ◽  
Author(s):  
T. I. Ivanov ◽  
M. Roudjane ◽  
M. O. Vieitez ◽  
C. A. de Lange ◽  
W.-Ü L. Tchang-Brillet ◽  
...  

1999 ◽  
Vol 192 ◽  
pp. 420-426
Author(s):  
Alan B. Whiting

The present kinematics of an unrelaxed system such as the Local Group can be used to investigate its dynamics on a cosmological time scale. In particular, the classical timing argument of Kahn & Woltjer may be extended to distant satellite galaxies of the Local Group whose distances and velocities are known with some accuracy. Including a correction for the fact that the Local Group was not always dynamically isolated, I derive a mass for the Group of about 1.6 x 1012M⊙ and an age of 1.0 to 1.2 x 1010 years.


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