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Nucleosynthesis, Cosmic Radiation, and the Universe
Published in Ivan G. Draganić, Zorica D. Draganić, Jean-Pierre Adloff, Radiation and Radioactivity on Earth and Beyond, 2020
Ivan G. Draganić, Zorica D. Draganić, Jean-Pierre Adloff
The model does not account for the origin of the singularity. Moreover, the process begins within a small fraction of a second after the Big Bang. After 10−43 second the gravity force separates and becomes independent from the other three (strong, weak, and electromagnetic). The strong force emerges as an independent entity after 1035 second. It causes a rapid expansion of the universe (between 10 35 and 10 32 second) without involving appreciable cooling; this is the so-called inflationary period. Adding such a period to the theory helps to solve some problems of the classical Big Bang cosmology. It also offers new possibilities such as the existence of cosmic strings. These are one-dimensional relics of the early universe with a huge mass per unit length; 1000 million tons per centimeter.
The Legacy of the Sun
Published in Wolfgang Palz, The Triumph of the Sun in 2000–2020, 2019
However, there are a lot of mysteries—one being the “big bang”. How could it be that this enormous Universe developed at one point in time from a ball not bigger than a nailhead? Only in 1927–1929 Edwin Hubble and the Belgian priest Georges Lemaître discovered the big bang and the eternal expansion of the Universe. The expansion follows a precise speed, the Hubble constant.
The Legacy of the Sun
Published in Wolfgang Palz, The Triumph of the Sun, 2018
However, there are a lot of mysteries—one being the “big bang”. How could it be that this enormous Universe developed at one point in time from a ball not bigger than a nailhead? Only in 1927–1929 Edwin Hubble and the Belgian priest Georges Lemaître discovered the big bang and the eternal expansion of the Universe. The expansion follows a precise speed, the Hubble constant.
Geometric theory of topological defects: methodological developments and new trends
Published in Liquid Crystals Reviews, 2021
Sébastien Fumeron, Bertrand Berche, Fernando Moraes
Cosmic inflation is a period of extremely fast expansion of the Universe scale factor (typically a factor within seconds) that presumably happened at the very beginning of the universe [79]. From the point of view of statistical physics, inflation is nothing more than a quench and as such, it is likely to favor the formation of topological defects. In 1976 [80], Tom Kibble introduced a three-step mechanism (later refined by Zurek [81] who included the sensitivity to the quench speed) to describe the details of this quench. Basically, the Kibble-Zurek mechanism (KZM) consists in a nucleation process very similar to what happens at the isotropic-nematic phase transition, but instead of having an order locally described by the director field , it is here described by the phase of a complex scalar field generically called a Higgs field – or an inflaton, because it need not be the Higgs field responsible for the later breaking of electroweak symmetry. First, ordered protodomains (analog to the nematic spherulites) with no correlation between each other are formed and at the scale of a whole protodomain, the fast temperature drop due to inflation causes the Higgs field to locally take a non-vanishing vacuum expectation value and hence make a phase choice. Then the protodomains grow in size until they coalesce. But as they were not correlated, the choices for the Higgs phase (technically, its vacuum expectation value) do not match in general, and line singularities of the Higgs appear when the boundaries of protodomains finally meet. These linear singularities are called cosmic strings.
The Response of Matter to Spatially Distributed Transient Energy Addition: An Asymptotic Analysis”: Part 1, Inert Gases
Published in Combustion Science and Technology, 2022
The interaction of matter and energy is fundamental to the physics occurring in systems with radically diverse length and time scales, as well as magnitudes of energy deposition. Cosmologists believe that the accelerating expansion of the universe can be attributed to the action of dark energy on the various forms of matter present (Riess et al. 1988). Supernovas, are transient astronomical events characterized by powerful and luminous stellar explosions occurring during the last evolutionary stages of a massive star or when a white dwarf is triggered into runaway nuclear fusion (Riess et al. 2004). Massive amounts of thermonuclear energy are produced within a star causing an explosion which distributes its substance into the surrounding volume of space and often produces sufficient radiation in the visible spectrum to make the supernova visible from Earth in the daytime sky (Howell 2013). Nuclear fusion may be ignited by the deposition of sufficient energy on an appropriately short time scale (Ledingham et al. 2020). A recent experiment employed powerful lasers focused on a BB sized spot of heavy hydrogen to produce a hotspot the diameter of a human hair. It generated more than 10 quadrillion watts of fusion power for 100 trillionths of a second. Lightning causes the air though which it passes in a tiny fraction of a second to be heated to temperatures estimated to be as large as 50,000 F or 28,033 K (Uman 1969) accompanied by a high pressure relative to that in the undisturbed air. The subsequent expansion of the hot gas (the piston effect (Kevorkian and Cole 1981)) is the source of a shock wave (heard as a “bang”as it passes the ear) followed by a high velocity turbulent gas flow, one source of familiar rolling thunder. The piston effect is also responsible for the blast wave generated by nuclear or conventional explosions. Thermonuclear energy deposition in the former and chemical energy in the latter are the sources of a pronounced gasdynamical response (Kassoy 2010) in the initially undisturbed gas. Instabilities occurring in rocket engine combustion chambers are examples of the dynamic response of the combustion gases to chemically generated sources of energy (Sirignano 2015).