scholarly journals Review on Natural, Incidental, Bioinspired, and Engineered Nanomaterials: History, Definitions, Classifications, Synthesis, Properties, Market, Toxicities, Risks, and Regulations

Nanomaterials ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 177
Author(s):  
Ahmed Barhoum ◽  
María Luisa García-Betancourt ◽  
Jaison Jeevanandam ◽  
Eman A. Hussien ◽  
Sara A. Mekkawy ◽  
...  
Keyword(s):  
Nanostructured Materials ◽  
Environmental Remediation ◽  
Large Scale ◽  
Big Bang ◽  
Industrial Applications ◽  
Diagnostic Tools ◽  
Biochemical Engineering ◽  
Synthesis Properties ◽  
Nanomaterials Synthesis ◽  
The Big Bang

Nanomaterials are becoming important materials in several fields and industries thanks to their very reduced size and shape-related features. Scientists think that nanoparticles and nanostructured materials originated during the Big Bang process from meteorites leading to the formation of the universe and Earth. Since 1990, the term nanotechnology became very popular due to advances in imaging technologies that paved the way to specific industrial applications. Currently, nanoparticles and nanostructured materials are synthesized on a large scale and are indispensable for many industries. This fact fosters and supports research in biochemistry, biophysics, and biochemical engineering applications. Recently, nanotechnology has been combined with other sciences to fabricate new forms of nanomaterials that could be used, for instance, for diagnostic tools, drug delivery systems, energy generation/storage, environmental remediation as well as agriculture and food processing. In contrast with traditional materials, specific features can be integrated into nanoparticles, nanostructures, and nanosystems by simply modifying their scale, shape, and composition. This article first summarizes the history of nanomaterials and nanotechnology. Followed by the progress that led to improved synthesis processes to produce different nanoparticles and nanostructures characterized by specific features. The content finally presents various origins and sources of nanomaterials, synthesis strategies, their toxicity, risks, regulations, and self-aggregation.

scholarly journals Relativistic Cosmology with an Introduction to Inflation

Universe ◽  
2021 ◽  
Vol 7 (8) ◽  
pp. 276
Author(s):  
Muhammad Zahid Mughal ◽  
Iftikhar Ahmad ◽  
Juan Luis García Guirao
Keyword(s):  
Standard Model ◽  
Early Universe ◽  
Large Scale ◽  
Initial Conditions ◽  
Big Bang ◽  
Relativistic Cosmology ◽  
The Standard Model ◽  
Big Bang Model ◽  
The Big Bang ◽  
The Universe

In this review article, the study of the development of relativistic cosmology and the introduction of inflation in it as an exponentially expanding early phase of the universe is carried out. We study the properties of the standard cosmological model developed in the framework of relativistic cosmology and the geometric structure of spacetime connected coherently with it. The geometric properties of space and spacetime ingrained into the standard model of cosmology are investigated in addition. The big bang model of the beginning of the universe is based on the standard model which succumbed to failure in explaining the flatness and the large-scale homogeneity of the universe as demonstrated by observational evidence. These cosmological problems were resolved by introducing a brief acceleratedly expanding phase in the very early universe known as inflation. The cosmic inflation by setting the initial conditions of the standard big bang model resolves these problems of the theory. We discuss how the inflationary paradigm solves these problems by proposing the fast expansion period in the early universe. Further inflation and dark energy in fR modified gravity are also reviewed.

scholarly journals Primordial Magnetic Field Effects on the CMB and Large-Scale Structure

2010 ◽  
Vol 2010 ◽  
pp. 1-19 ◽  
Author(s):  
Dai G. Yamazaki ◽  
Kiyotomo Ichiki ◽  
Toshitaka Kajino ◽  
Grant J. Mathews
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Large Scale ◽  
Large Scale Structure ◽  
Big Bang ◽  
Scale Structure ◽  
Magnetic Field Effects ◽  
Power Spectral ◽  
Primordial Magnetic Field ◽  
The Big Bang

Magnetic fields are everywhere in nature, and they play an important role in every astronomical environment which involves the formation of plasma and currents. It is natural therefore to suppose that magnetic fields could be present in the turbulent high-temperature environment of the big bang. Such a primordial magnetic field (PMF) would be expected to manifest itself in the cosmic microwave background (CMB) temperature and polarization anisotropies, and also in the formation of large-scale structure. In this paper, we summarize the theoretical framework which we have developed to calculate the PMF power spectrum to high precision. Using this formulation, we summarize calculations of the effects of a PMF which take accurate quantitative account of the time evolution of the cutoff scale. We review the constructed numerical program, which is without approximation, and an improvement over the approach used in a number of previous works for studying the effect of the PMF on the cosmological perturbations. We demonstrate how the PMF is an important cosmological physical process on small scales. We also summarize the current constraints on the PMF amplitudeBλand the power spectral indexnBwhich have been deduced from the available CMB observational data by using our computational framework.

scholarly journals COSMOLOGICAL CONSTRAINTS FOR THE COSMIC DEFECT THEORY

2011 ◽  
Vol 20 (06) ◽  
pp. 1039-1051 ◽  
Author(s):  
NINFA RADICELLA ◽  
MAURO SERENO ◽  
ANGELO TARTAGLIA
Keyword(s):  
Large Scale ◽  
Hubble Constant ◽  
Big Bang ◽  
Nuclear Species ◽  
Type Ia ◽  
Species Abundances ◽  
Age Of The Universe ◽  
Ia Supernovae ◽  
The Big Bang ◽  
The Universe

The cosmic defect theory has been confronted with four observational constraints: primordial nuclear species abundances emerging from the big bang nucleosynthesis; large scale structure formation in the Universe; cosmic microwave background acoustic scale; luminosity distances of type Ia supernovae. The test has been based on a statistical analysis of the a posteriori probabilities for three parameters of the theory. The result has been quite satisfactory and such that the performance of the theory is not distinguishable from that of the ΛCDM theory. The use of the optimal values of the parameters for the calculation of the Hubble constant and the age of the Universe confirms the compatibility of the cosmic defect approach with observations.

Big Bang Theory

2018 ◽  
Author(s):  
Matthew Y. Heimburger
Keyword(s):  
Large Scale ◽  
Mechanistic Model ◽  
Albert Einstein ◽  
Physical World ◽  
Big Bang ◽  
Scientific Model ◽  
Social Sciences And Humanities ◽  
Big Bang Theory ◽  
The Big Bang ◽  
The Universe

The Big Bang theory is a scientific model of the universe that posits a state of dense, centralized matter before the current, observable expansion of the universe in one giant explosion. While ‘the Big Bang’ was a phrase first used somewhat facetiously by British astronomer Fred Hoyle in 1949, it rested on earlier theories and observations by George Lamaitre, Albert Einstein, and Edwin Hubble. The implications of Big Bang theory have been far-reaching. For some, the Big Bang’s suggestion of a ‘beginning of time’ lent itself to familiar religious teleology. For others, it provided a rigid, mechanistic model of the physical world, which in turn affected ideas in the social sciences and humanities. This is not to say that Big Bang theory was a ‘grand unifying theory’—even in the 1920s, the rather precise predictions of Einstein’s theories of relativity conflicted with the conclusions of Heisenberg’s Uncertainty Principle and quantum mechanics. Still, the idea that the physical world exists due to the violent expansion (and subsequent contraction) of matter suggests a rather small place for humanity in the larger scheme of things. There is little room or need for free will in such a system—at least when it comes to matters of large-scale significance. Today, the Big Bang often stands as a euphemism for debates over God and human determinism in the universe, and lends itself to philosophic traditions such as nihilism and existentialism.

scholarly journals Large Scale Anisotropy of the Cosmic Microwave Background

1974 ◽  
Vol 63 ◽  
pp. 157-162 ◽  
Author(s):  
R. B. Partridge
Keyword(s):  
Angular Distribution ◽  
Large Scale ◽  
Background Radiation ◽  
Big Bang ◽  
Microwave Background ◽  
Initial State ◽  
Microwave Background Radiation ◽  
Cosmological Data ◽  
The Big Bang ◽  
The Universe

It is now generally accepted that the microwave background radiation, discovered in 1965 (Penzias and Wilson, 1965; Dicke et al., 1965), is cosmological in origin. Measurements of the spectrum of the radiation, discussed earlier in this volume by Blair, are consistent with the idea that the radiation is in fact a relic of a hot, dense, initial state of the Universe – the Big Bang. If the radiation is cosmological, measurements of both its spectrum and its angular distribution are capable of providing important – and remarkably precise – cosmological data.

The Development of Physical Cosmology

2020 ◽  
pp. 3-226
Author(s):  
P. J. E. Peebles
Keyword(s):  
Particle Physics ◽  
Large Scale ◽  
Big Bang ◽  
Stellar Astronomy ◽  
Basic Physics ◽  
Substantial Progress ◽  
Physical Cosmology ◽  
The Big Bang ◽  
The Universe ◽  
Opening Up

This chapter introduces physical cosmology as the attempt to make sense of the large-scale nature of the material world by the methods of the natural sciences. It explains that physical cosmology operates under the special restrictions of astronomy, which is considered successful in sister fields, such as stellar astronomy and particle physics. It cites the substantial progress of cosmology as an enterprise in physical science, although the advances certainly have moved around considerable gaps in one's understanding. The chapter details how cosmology inherits from basic physics the more ancient and honorable tradition of attempts to understand where the world came from, where it is going, and why. It reviews believable evidence that the universe is expanding, the space between the galaxies opening up, and that this expansion traces back to a hot dense phase, the big bang.

scholarly journals STRUCTURE FORMATION WITH MIRROR DARK MATTER: CMB AND LSS

2005 ◽  
Vol 14 (01) ◽  
pp. 107-119 ◽  
Author(s):  
ZURAB BEREZHIANI ◽  
PAOLO CIARCELLUTI ◽  
DENIS COMELLI ◽  
FRANCESCO L. VILLANTE
Keyword(s):  
Dark Matter ◽  
Structure Formation ◽  
Large Scale ◽  
Cold Dark Matter ◽  
Big Bang ◽  
Dark Matter Candidate ◽  
Microwave Background ◽  
Quantitative Calculation ◽  
World Hypothesis ◽  
The Big Bang

In the mirror world hypothesis, the mirror baryonic component emerges as a possible dark matter candidate. An immediate question arises: how do the mirror baryons behave and what are their differences from the more familiar dark matter candidates such as cold dark matter? In this paper, we answer this question quantitatively. First, we discuss the dependence of the relevant scales for the structure formation (Jeans and Silk scales) on the two macroscopic parameters necessary to define the model: the temperature of the mirror plasma (limited by the Big Bang Nucleosynthesis) and the amount of mirror baryonic matter. Then we perform a complete quantitative calculation of the implications of mirror dark matter on the cosmic microwave background and large scale structure power spectrum. Finally, confronting with the present observational data, we obtain some bounds on the mirror parameter space.

scholarly journals THE CONCEPT OF «MEGASIENCE» CLASS PROJECTS: THE CASE OF ITER AND FAIR INSTALLATIONS

2019 ◽  
pp. 205-213 ◽  
Author(s):  
E. N. GORLOVA ◽  
R. V. TKACHENKO
Keyword(s):  
Large Scale ◽  
Big Bang ◽  
Progressive Movement ◽  
Global Challenge ◽  
Increase Energy Efficiency ◽  
Global Problems ◽  
Scientific Results ◽  
The Big Bang ◽  
Structure Of Matter ◽  
The Universe

International scientific projects aimed at the creation and operation of megasiens class facilities and, accordingly, at obtaining breakthrough, innovative scientific results of global significance are called megascience class projects. Currently, there are several large-scale megasiens projects in the world, each of which is aimed at addressing the global challenge facing humanity. The next qualitative stage in the development of civilization is impossible without the elimination of bottlenecks that prevent such a progressive movement. One of the most pressing global problems is to increase energy efficiency and develop technologies for obtaining and using alternative renewable sources of electric and thermal energy, as well as gaining new knowledge about the structure of matter and the evolution of the Universe from the Big Bang to the present. The megascience projects of ITER and FAIR are called to solve these problems, an important role in the financing and technical implementation of which is played by the Russian Federation.

scholarly journals Of Cosmic Background Anisotropies

1996 ◽  
Vol 168 ◽  
pp. 31-44
Author(s):  
G.F. Smoot
Keyword(s):  
Large Scale ◽  
Thermal Emission ◽  
Big Bang ◽  
Microwave Background ◽  
The Standard Model ◽  
The Big Bang ◽  
The Universe ◽  
Fundamental Physical ◽  
Large Scale Structure Formation

Observations of the Cosmic Microwave Background (CMB) Radiation have put the standard model of cosmology, the Big Bang, on firm footing and provide tests of various ideas of large scale structure formation. CMB observations now let us test the role of gravity and General Relativity in cosmology including the geometry, topology, and dynamics of the Universe. Foreground galactic emissions, dust thermal emission and emission from energetic electrons, provide a serious limit to observations. Nevertheless, observations may determine if the evolution of the Universe can be understood from fundamental physical principles.

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