scholarly journals O UNIVERSO VIVO

2012 ◽  
Vol 19 (1.2) ◽  
Author(s):  
Francisco César de Sá Barreto ◽  
Luiz Paulo Ribeiro Vaz ◽  
Gabriel Armando Pellegatti Franco
Keyword(s):  
Cosmological Model ◽  
Chemical Elements ◽  
Big Bang ◽  
Living System ◽  
Irreversible Processes ◽  
Thermodynamics Of Irreversible Processes ◽  
Protons And Neutrons ◽  
Standard Cosmological Model ◽  
The Big Bang ◽  
The Universe

The standard cosmological model suggests that after the “Big Bang”, 14 billion of years ago, the universe entered a period of expansion and cooling. In the first one millionth of a second appear quarks, glúons, electrons and neutrinos, followed by the appearance of protons and neutrons. In this paper, we describe the “cosmic battle” between gravitation and energy, responsible for the lighter chemical elements and the formation of the stars. We describe the thermodynamics of irreversible processes of systems which are far away from equilibrium, a route that is followed by the universe, seen as a living system.

scholarly journals Augustine of Hippo’s Philosophy of Time Meets General Relativity

KronoScope ◽  
2014 ◽  
Vol 14 (1) ◽  
pp. 71-89 ◽  
Author(s):  
Ettore Minguzzi
Keyword(s):  
General Relativity ◽  
Cosmological Model ◽  
Degrees Of Freedom ◽  
Big Bang ◽  
Null Hypersurface ◽  
Philosophy Of Time ◽  
The Big Bang ◽  
The Universe

Abstract This paper proposes a cosmological model that uses a causality argument to solve the homogeneity and entropy problems of cosmology. In this model, a chronology violating region of spacetime causally precedes the remainder of the Universe, and a theorem establishes the existence of time functions precisely outside the chronology violating region. This model is shown to nicely reproduce Augustine of Hippo’s thought on time and the beginning of the Universe. In the model, the spacelike boundary representing the Big Bang is replaced by a null hypersurface at which the gravitational degrees of freedom are almost frozen while the matter and radiation content is highly homogeneous and thermalized.

scholarly journals From cosmos to intelligent life: the four ages of astrobiology

2012 ◽  
Vol 11 (4) ◽  
pp. 345-350 ◽  
Author(s):  
Marcelo Gleiser
Keyword(s):  
Chemical Elements ◽  
Life Forms ◽  
Big Bang ◽  
Self Awareness ◽  
First Stars ◽  
History Of ◽  
Life On Earth ◽  
The Big Bang ◽  
The Universe ◽  
Intelligent Life

AbstractThe history of life on Earth and in other potential life-bearing planetary platforms is deeply linked to the history of the Universe. Since life, as we know, relies on chemical elements forged in dying heavy stars, the Universe needs to be old enough for stars to form and evolve. The current cosmological theory indicates that the Universe is 13.7 ± 0.13 billion years old and that the first stars formed hundreds of millions of years after the Big Bang. At least some stars formed with stable planetary systems wherein a set of biochemical reactions leading to life could have taken place. In this paper, I argue that we can divide cosmological history into four ages, from the Big Bang to intelligent life. The physical age describes the origin of the Universe, of matter, of cosmic nucleosynthesis, as well as the formation of the first stars and Galaxies. The chemical age began when heavy stars provided the raw ingredients for life through stellar nucleosynthesis and describes how heavier chemical elements collected in nascent planets and Moons gave rise to prebiotic biomolecules. The biological age describes the origin of early life, its evolution through Darwinian natural selection and the emergence of complex multicellular life forms. Finally, the cognitive age describes how complex life evolved into intelligent life capable of self-awareness and of developing technology through the directed manipulation of energy and materials. I conclude discussing whether we are the rule or the exception.

scholarly journals Explosive Cosmogony and the Quasi-Steady State Cosmology

1999 ◽  
Vol 183 ◽  
pp. 286-289 ◽  
Author(s):  
G. Burbidge
Keyword(s):  
Chemical Elements ◽  
Early Stage ◽  
Black Body ◽  
Big Bang ◽  
Body Form ◽  
Protons And Neutrons ◽  
History Of ◽  
The Right ◽  
The Universe ◽  
Distance Relation

Modern cosmology began with the realization that there were solutions to Einstein's theory of gravity discovered by Friedmann and Lemaitre which when combined with the redshift distance relation of Hubble and others could be interpreted as showing that we live in an expanding universe. By 1930, the scientific establishment and many of the lay public believed this. It was then only elementary logic to argue that if time reversal was applied, the universe must originally have been so compact that we could talk of a beginning. Lemaitre tried to describe this state as the “Primeval Atom.” For a decade or so after the war, Gamow, Alpher and Herman and other leading physicists explored this dense configuration trying to make the chemical elements from protons and neutrons. They soon learned that this was not possible because of the absence of stable masses of five and eight, but they also realized that if such an early stage had occurred the universe would contain an expanding cloud of radiation which would preserve its black body form. Dicke and his colleagues in Princeton rediscovered this idea and decided to try and detect the radiation. Penzias and Wilson found such a radiation field, and COBE has demonstrated that it has a perfect black body form out to radio wavelengths. This history of the discovery together with the fact that the light elements D, He3 and He4 in about the right amounts can be made in a hot big bang has led to the widely held, but simplistic view, that the standard cosmology - the hot big bang - is correct.

A holographic big bang?

2015 ◽  
Vol 24 (12) ◽  
pp. 1544029
Author(s):  
N. Afshordi ◽  
R. B. Mann ◽  
R. Pourhasan
Keyword(s):  
Cosmological Model ◽  
Big Bang ◽  
Initial Singularity ◽  
Scale Invariant ◽  
The Big Bang ◽  
The Universe ◽  
Important Test

We present a cosmological model in which the Universe emerges out of the collapse of a five-dimensional (5D) star as a spherical three-brane. The initial singularity of the big bang becomes hidden behind a causal horizon. Near scale-invariant primordial curvature perturbations can be induced on the brane via a thermal atmosphere that is in equilibrium with the brane, circumventing the need for a separate inflationary process and providing an important test of the model.

scholarly journals THE BIG BANG AS A PHASE TRANSITION

2005 ◽  
Vol 20 (10) ◽  
pp. 2037-2045 ◽  
Author(s):  
TOMÁŠ LIKO ◽  
PAUL S. WESSON
Keyword(s):  
Phase Transition ◽  
Cosmological Model ◽  
Big Bang ◽  
The Big Bang ◽  
The Universe

We study a five-dimensional cosmological model, which suggests that the universe began as a discontinuity in a scalar (Higgs-type) field, or alternatively as a conventional four-dimensional phase transition.

8. Where do the elements come from?

2019 ◽  
pp. 117-131
Author(s):  
Geoff Cottrell
Keyword(s):  
Neutron Stars ◽  
Chemical Elements ◽  
Big Bang ◽  
Life Cycles ◽  
Light Elements ◽  
Hydrogen Atoms ◽  
The Big Bang ◽  
The Universe ◽  
Made In

To understand where the chemical elements came from, we look at the earliest moments of the universe. ‘Where do the elements come from?’ traces the evolution of all the matter and energy in the universe, starting from a fraction of a second after its birth in the ‘Big Bang’, 13.8 billion years ago. The light elements, for example the hydrogen atoms in your body, were made in the Big Bang. The middleweight elements, such as carbon and oxygen, were (and still are being) forged deep inside stars, while the heavyweight elements, like gold and platinum, were produced in violent stellar explosions. The life cycles of stars, including supernovae, neutron stars, and pulsars is outlined.

scholarly journals Accelerating cosmologies with nonlinear electrodynamics

2018 ◽  
Vol 96 (9) ◽  
pp. 992-998
Author(s):  
G.P. Singh ◽  
N. Hulke ◽  
Ashutosh Singh
Keyword(s):  
Cosmological Model ◽  
Apparent Horizon ◽  
Second Law Of Thermodynamics ◽  
Big Bang ◽  
Accelerated Expansion ◽  
Nonlinear Electrodynamics ◽  
Classical Stability ◽  
Initial Anisotropy ◽  
The Big Bang ◽  
The Universe

In this paper, we consider the framework of nonlinear electrodynamics in locally rotationally symmetric (LRS) Bianchi-I universe model composed of magnetic fluid. It has been shown that an accelerated universe expansion takes place if the nonlinear electromagnetic field is a source of gravitational field. In this model, after the big bang, the universe undergoes inflation and the accelerated expansion, dissipates the initial anisotropy of the curvature part without using a selected initial condition. Further validity of generalised second law of thermodynamics in the cosmological model enclosed by apparent horizon is investigated. We also discuss the classical stability of the cosmological model and observational viability of the model.

The Big Bang: status and prospects

2002 ◽  
Vol 10 (2) ◽  
pp. 221-236 ◽  
Author(s):  
ANDREW R. LIDDLE
Keyword(s):  
Dark Matter ◽  
Dark Energy ◽  
20Th Century ◽  
Chemical Elements ◽  
Big Bang ◽  
Great Success ◽  
Wide Range ◽  
Significant Figures ◽  
The Big Bang ◽  
The Universe

The 20th century saw the establishment of the first quantitative theory seeking to describe the behaviour of the Universe as a whole – the Big Bang. This sets up a framework within which there has been great success in interpreting a wide range of observations, including the abundances of light chemical elements, the existence and spectrum of the cosmic microwave radiation, and the formation and evolution of galaxies. At the end of the 20th century, the surprising conclusion of the Big Bang theory is that 95% of the Universe is made of two different unknown types of material whose nature remains unclear: dark matter and dark energy. Needless to say, this is a major challenge for science. At the beginning of the 21st century, cosmology appears poised to enter a high-precision era, where the key quantities of cosmology will be determined to two or more significant figures. If cosmologists are on the right track, this will confirm the existence of dark matter and dark energy; if not, it will force us to revise our current picture of the Universe. Either way, the prospect is for exciting years ahead in cosmology.

scholarly journals Development of George Gamow to the «Theory of great explosion»

2016 ◽  
Vol 6 (9) ◽  
pp. 217-222
Author(s):  
K. Sinyagina
Keyword(s):  
Chemical Elements ◽  
Big Bang ◽  
Microwave Background ◽  
George Gamow ◽  
Origin And Evolution ◽  
The Past ◽  
Higher Temperature ◽  
The Big Bang ◽  
The City ◽  
The Universe

This article considers the key-ideas for modern scientific understanding of the origin and evolution of the Universe. George Gamow is one of the first scientists to create the theory of the Big Bang the theory of great explosion. Gamow is a famous physicist who came from the city of Odessa (Ukraine) andgot interested in the origin of chemical elements. He suggested that in the past of the Universe before it had been created by the «Big Bang» (the theory of great explosion), the Universe had had much more substantial density and higher temperature than now. He was the first person to focus on unique properties of the Universe and to suggest existence of cosmic microwave background (CMB). The following disclosure of the CMB started the era of modern cosmology.

scholarly journals An Idea about Negative Cosmic Time in the Big Bang-Big Rip Cosmological Model

2021 ◽  
Author(s):  
Mohamed Abdalla Bakry ◽  
Ali Eid ◽  
A. Alkaoud
Keyword(s):  
Cosmological Model ◽  
Cosmic Time ◽  
Spherical Shape ◽  
Big Bang ◽  
Big Rip ◽  
The Moment ◽  
In The Beginning ◽  
The Big Bang ◽  
Negative Time ◽  
The Universe

In this article, we assume that the beginning of the universe was before the Big Bang. In the beginning, all matter in the universe was combined in an infinitesimal spherical shape. This sphere was compressed to an incomprehensible value for a period, and then exploded and expanded time and space. We are referring to the negative time before the Big Bang. The evolution of the universe before the Big Bang, passing through the moment of the explosion to the end of the universe at the Big Rip, has been studied. In this article, we try to answer the questions; did the universe exist before the Big Bang? What is the origin of the universe and how did it arise? What are the stages of the evolution of the universe until the moment of the Big Rip? What is the length of time for the stages of this development?

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