scholarly journals Introduction to big bang nucleosynthesis and modern cosmology

2017 ◽  
Vol 26 (08) ◽  
pp. 1741001 ◽  
Author(s):  
Grant J. Mathews ◽  
Motohiko Kusakabe ◽  
Toshitaka Kajino
Keyword(s):  
Nuclear Reactions ◽  
Big Bang ◽  
Cosmological Models ◽  
Big Bang Nucleosynthesis ◽  
Primordial Nucleosynthesis ◽  
Current State ◽  
Modern Cosmology ◽  
Basic Equations ◽  
The Big Bang ◽  
The Universe

Primordial nucleosynthesis remains as one of the pillars of modern cosmology. It is the testing ground upon which many cosmological models must ultimately rest. It is our only probe of the universe during the important radiation-dominated epoch in the first few minutes of cosmic expansion. This paper reviews the basic equations of space-time, cosmology, and big bang nucleosynthesis. We also summarize the current state of observational constraints on primordial abundances along with the key nuclear reactions and their uncertainties. We summarize which nuclear measurements are most crucial during the big bang. We also review various cosmological models and their constraints. In particular, we analyze the constraints that big bang nucleosynthesis places upon the possible time variation of fundamental constants, along with constraints on the nature and origin of dark matter and dark energy, long-lived supersymmetric particles, gravity waves, and the primordial magnetic field.

Naming the Big Bang

2012 ◽  
Vol 44 (1) ◽  
pp. 3-36 ◽  
Author(s):  
Helge Kragh
Keyword(s):  
Scientific Community ◽  
Big Bang ◽  
Consensus Model ◽  
Initial State ◽  
The Standard Model ◽  
Modern Cosmology ◽  
Fred Hoyle ◽  
The Big Bang ◽  
The Universe ◽  
Origin Of The Universe

The standard model of modern cosmology is known as the hot big bang, a name that refers to the initial state of the universe some fourteen billion years ago. The name Big Bang introduced by Fred Hoyle in 1949 is one of the most successful scientific neologisms ever. How did the name originate and how was it received by physicists and astronomers in the period leading up to the hot big bang consensus model in the late 1960s? How did it reflect the meanings of the origin of the universe, a concept that predates the name by nearly two decades? Contrary to what is often assumed, the name was not an instant success—it took more than twenty years before Big Bang became a household word in the scientific community. When it happened, it was used with different connotations, as is still the case. Moreover, it was used earlier and more frequently in popular than in scientific contexts, and not always relating to cosmology. It turns out that Hoyle’s celebrated name has a richer and more surprising history than commonly assumed and also that the literature on modern cosmology and its history includes many common mistakes and errors. An etymological approach centering on the name Big Bang provides supplementary insight to the historical understanding of the emergence of modern cosmology.

scholarly journals Big Bang Nucleosynthesis in Visible and Hidden-Mirror Sectors

2014 ◽  
Vol 2014 ◽  
pp. 1-7
Author(s):  
Paolo Ciarcelluti
Keyword(s):  
Dark Matter ◽  
Building Blocks ◽  
Big Bang ◽  
Dark Matter Candidate ◽  
Big Bang Nucleosynthesis ◽  
Enhanced Production ◽  
The Standard Model ◽  
The Big Bang ◽  
The Universe ◽  
Mirror Matter

One of the still viable candidates for the dark matter is the so-called mirror matter. Its cosmological and astrophysical implications were widely studied, pointing out the importance to go further with research. In particular, the Big Bang nucleosynthesis provides a strong test for every dark matter candidate, since it is well studied and involves relatively few free parameters. The necessity of accurate studies of primordial nucleosynthesis with mirror matter has then emerged. I present here the results of accurate numerical simulations of the primordial production of both ordinary nuclides and nuclides made of mirror baryons, in presence of a hidden mirror sector with unbroken parity symmetry and with gravitational interactions only. These elements are the building blocks of all the structures forming in the Universe; therefore, their chemical composition is a key ingredient for astrophysics with mirror dark matter. The production of ordinary nuclides shows differences from the standard model for a ratio of the temperatures between mirror and ordinary sectorsx=T′/T≳0.3, and they present an interesting decrease of the abundance ofLi7. For the mirror nuclides, instead, one observes an enhanced production ofHe4, which becomes the dominant element forx≲0.5, and much larger abundances of heavier elements.

THE DISCOVERY OF THE EXPANDING UNIVERSE AND 80 YEARS OF BIG BANG

2011 ◽  
Vol 20 (supp01) ◽  
pp. 87-103 ◽  
Author(s):  
HARRY NUSSBAUMER
Keyword(s):  
Big Bang ◽  
Rapid Expansion ◽  
Condensed State ◽  
De Sitter ◽  
Static Universe ◽  
Linear Distance ◽  
Velocity Relationship ◽  
Modern Cosmology ◽  
The Big Bang ◽  
The Universe

Modern cosmology began in 1917 when Einstein published his model of a static Universe built on general relativity. A few months later de Sitter came forward with a competing, but also static model which contained no matter but had the intriguing quality that the spectrum of a test particle appeared redshifted to a distant observer. It was thought that de Sitter's model might explain the redshifted spectra observed by Slipher in spiral nebulae. However, in 1927 Lemaître showed that de Sitter's model violated the principle of homogeneity. He then formulated a dynamical cosmological model and combined it with the available observations, showing that our Universe is expanding. He theoretically derived the linear distance–velocity relationship which today is called the "Hubble-relation." Hubble confirmed the relation in 1929 on purely observational grounds. 80 years ago, in 1931 in a letter to Nature, Lemaître suggested that the Universe had a definite beginning in a rapid expansion out of a highly condensed state: the primeval atom. This event became later known as the Big Bang.

A critical analysis of the Big Bang Nucleosynthesis

2019 ◽  
Vol 34 (24) ◽  
pp. 1950194 ◽  
Author(s):  
Tahani R. Makki ◽  
Mounib F. El Eid ◽  
Grant J. Mathews
Keyword(s):  
Critical Analysis ◽  
Big Bang ◽  
Early Evolution ◽  
Big Bang Nucleosynthesis ◽  
Evolution Of The Universe ◽  
Chemical Potentials ◽  
Primordial Abundance ◽  
The Big Bang ◽  
The Universe

Standard Big Bang Nucleosynthesis (SBBN) represents one of the basic tools to understand the early evolution of the universe. In this paper, we reanalyze this process to focus on the so-called lithium problem. 7Li is overproduced during SBBN compared to its primordial abundance as obtained from observations. For this reason, we extend the scenarios of SBBN in two directions: (i) equating all neutrino chemical potentials and including more neutrino families, (ii) varying neutrino chemical potentials independently. Since the so-called cosmological lithium problem is not resolved on nuclear/astrophysical ground, we argue that this problem should be examined by invoking nonstandard assumptions.

scholarly journals Physics Essay: Six Baseless and Irrational Problems in Modern Cosmology

2015 ◽  
Vol 7 (6) ◽  
pp. 56
Author(s):  
Zifeng Li
Keyword(s):  
Black Hole ◽  
Dimensional Space ◽  
Big Bang ◽  
Mass Energy ◽  
Curved Space ◽  
Big Bang Theory ◽  
Modern Cosmology ◽  
Hubble’S Law ◽  
The Big Bang ◽  
The Universe

<p class="1Body">Analyzes the Big Bang theory, recession of galaxies, Hubble's law, multi-dimensional space, curved space and black hole in modern cosmology and points out that these six theories are all baseless and irrational, contrary to classical science. Promotes the use of plain view of the universe - the materialist view of space–time-mass-energy to study the universe. The observations and understanding of the universe are very limited now. Cosmology should be realistic, not based on irrational models.</p>

scholarly journals The Spectrum of Gravitational Waves, Their Overproduction in Quintessential Inflation and Its Influence in the Reheating Temperature

Universe ◽  
2020 ◽  
Vol 6 (6) ◽  
pp. 87
Author(s):  
Jaume Haro Cases ◽  
Llibert Aresté Saló
Keyword(s):  
Phase Transition ◽  
Gravitational Waves ◽  
Particle Production ◽  
Big Bang ◽  
Kinetic Regime ◽  
Big Bang Nucleosynthesis ◽  
Inflaton Field ◽  
The Big Bang ◽  
The Universe

One of the most important issues in an inflationary theory as standard or quintessential inflation is the mechanism to reheat the universe after the end of the inflationary period in order to match with the Hot Big Bang universe. In quintessential inflation two mechanisms are frequently used, namely the reheating via gravitational particle production which is, as we will see, very efficient when the phase transition from the end of inflation to a kinetic regime (all the energy of the inflaton field is kinetic) is very abrupt, and the so-called instant preheating which is used for a very smooth phase transition because in that case the gravitational particle production is very inefficient. In the present work, a detailed study of these mechanisms is done, obtaining bounds for the reheating temperature and the range of the parameters involved in each reheating mechanism in order that the Gravitational Waves (GWs) produced at the beginning of kination do not disturb the Big Bang Nucleosynthesis (BBN) success.

scholarly journals The Big Bang, modern cosmology and the fate of the Universe: impacts upon culture

2009 ◽  
Vol 5 (S260) ◽  
pp. 33-38
Author(s):  
Lawrence M. Krauss
Keyword(s):  
Big Bang ◽  
Past Century ◽  
The Past ◽  
Fundamental Science ◽  
The World ◽  
Modern Cosmology ◽  
Equal Capacity ◽  
The Big Bang ◽  
The Universe

AbstractCosmological discoveries over the past century have completely changed our picture of our place in the universe. New observations have a realistic chance of probing nature on heretofore unimaginable scales, and as a result are changing the nature of fundamental science. Perhaps no other domain of science has an equal capacity to completely change our perspective of the world in which we live.

scholarly journals Connecting early and late universe by f(R) gravity

2015 ◽  
Vol 24 (04) ◽  
pp. 1541002 ◽  
Author(s):  
Salvatore Capozziello ◽  
Mariafelicia De Laurentis ◽  
Orlando Luongo
Keyword(s):  
Dark Energy ◽  
Review Paper ◽  
Big Bang ◽  
Present Stage ◽  
Fundamental Physics ◽  
Modern Cosmology ◽  
The Big Bang ◽  
Geometric Picture ◽  
The Universe

Inflation and dark energy are two of the most relevant aspects of modern cosmology. These different epochs provide the universe is passing through accelerated phases soon after the Big–Bang and at present stage of its evolution. In this review paper, we discuss that both eras can be, in principle, described by a geometric picture, under the standard of f(R) gravity. We give the fundamental physics motivations and outline the main ingredients of f(R) inflation, quintessence and cosmography. This wants to be a quick summary of f(R) paradigm without claiming of completeness.

Friedmann’s equation and the creation of the universe

2018 ◽  
Vol 27 (14) ◽  
pp. 1847013 ◽  
Author(s):  
Arthur E. Fischer
Keyword(s):  
Quadratic Form ◽  
Time Reversal ◽  
Infinite Dilution ◽  
Time Derivative ◽  
Big Bang ◽  
Cosmological Models ◽  
Derivative Formula ◽  
Physical Consequences ◽  
The Big Bang ◽  
The Universe

In this paper, we present mathematical evidence that the beginning of the universe did not occur at the big bang at [Formula: see text] with the universe in a state of infinite density, but occurred at [Formula: see text] with the universe in a state of infinite dilution. We show the essential importance played by the native quadratic structure of a generic Friedmann’s equation [Formula: see text] in the time derivative [Formula: see text] in arriving at this conclusion and show how this quadratic structure together with the accompanying time-reversal symmetry of Friedmann’s equation has profound physical consequences in building Friedmann models of the universe, one of which is that classical cosmological models can be extrapolated backward through the big bang into the infinite past. We conclude that viable cosmological models based on the native quadratic form of Friedmann’s equation, and thus on Einstein’s equations, show that global spatial singularities need not signal an end to spacetime. Moreover, classical big bang cosmological models based on Friedmann’s equation, without the need for quantum gravity, when globalized to all-time solutions, show that the universe did not begin at the big bang. Thus encoded in Friedmann’s equation is previously undiscovered information about how the universe began and we show that this information can only be extracted when Friedmann’s equation is taken in its native quadratic form as opposed to the usual approach of considering only the positive square root form of Friedmann’s equation.

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