scholarly journals Reconstructing the Cosmic Evolution of the Chemical Elements

Daedalus ◽  
2014 ◽  
Vol 143 (4) ◽  
pp. 71-80 ◽  
Author(s):  
Anna Frebel
Keyword(s):  
Chemical Analysis ◽  
Chemical Evolution ◽  
Milky Way ◽  
Chemical Elements ◽  
Big Bang ◽  
First Stars ◽  
Dense Cores ◽  
Cosmic Evolution ◽  
Supernova Explosions ◽  
The Big Bang

The chemical elements are created in nuclear fusion processes in the hot and dense cores of stars. The energy generated through nucleosynthesis allows stars to shine for billions of years. When these stars explode as massive supernovae, the newly made elements are expelled, chemically enriching the surrounding regions. Subsequent generations of stars are formed from gas that is slightly more element-enriched than that from which previous stars formed. This chemical evolution can be traced back to its beginning soon after the Big Bang by studying the oldest and most metal-poor stars still observable in the Milky Way today. Through chemical analysis, they provide the only available tool for gaining information about the nature of the short-lived first stars and their supernova explosions more than thirteen billion years ago. These events set in motion the transformation of the pristine universe into a rich cosmos of chemically diverse planets, stars, and galaxies.

scholarly journals Core Collapse Supernova Models and Nucleosynthesis

2013 ◽  
Vol 9 (S296) ◽  
pp. 27-36
Author(s):  
Ken'ichi Nomoto
Keyword(s):  
Big Bang ◽  
Elemental Abundance ◽  
Core Collapse ◽  
Solar Abundance ◽  
First Stars ◽  
Abundance Pattern ◽  
Core Collapse Supernova ◽  
Abundance Patterns ◽  
Supernova Explosions ◽  
The Big Bang

AbstractAfter the Big Bang, production of heavy elements in the early Universe takes place in the first stars and their supernova explosions. The nature of the first supernovae, however, has not been well understood. The signature of nucleosynthesis yields of the first supernovae can be seen in the elemental abundance patterns observed in extremely metal-poor stars. Interestingly, those abundance patterns show some peculiarities relative to the solar abundance pattern, which should provide important clues to understanding the nature of early generations of supernovae. We review the recent results of the nucleosynthesis yields of massive stars. We examine how those yields are affected by some hydrodynamical effects during the supernova explosions, namely, explosion energies from those of hypernovae to faint supernovae, mixing and fallback of processed materials, asphericity, etc. Those parameters in the supernova nucleosynthesis models are constrained from observational data of supernovae and metal-poor stars.

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.

4. What are planets made of?

2021 ◽  
pp. 47-75
Author(s):  
Raymond T. Pierrehumbert
Keyword(s):  
Life Cycle ◽  
Solar System ◽  
Milky Way ◽  
Planetary Systems ◽  
Big Bang ◽  
Heavy Elements ◽  
Milky Way Galaxy ◽  
First Stars ◽  
The Big Bang ◽  
The Universe

‘What are planets made of?’ assesses what planets are made of, beginning by looking at the life cycle of stars, and the kinds of stars which populate the Universe. Although the first stars of the Universe could not have formed planetary systems, the process did not take long to get under way. The Milky Way galaxy formed not long after the Big Bang and has been building its stock of heavy elements ever since. Thus, our Solar System incorporates ingredients from a mix of myriad expired stars, most of which have been processed multiple times through short-lived stars.

scholarly journals Exploring the origin of low-metallicity stars in Milky-Way-like galaxies with the NIHAO-UHD simulations

2020 ◽  
Vol 500 (3) ◽  
pp. 3750-3762
Author(s):  
Federico Sestito ◽  
Tobias Buck ◽  
Else Starkenburg ◽  
Nicolas F Martin ◽  
Julio F Navarro ◽  
...  
Keyword(s):  
High Resolution ◽  
Milky Way ◽  
Large Population ◽  
Big Bang ◽  
The Other ◽  
Cosmic Evolution ◽  
Early Formation ◽  
History Of ◽  
Low Metallicity ◽  
The Big Bang

ABSTRACT The kinematics of the most metal-poor stars provide a window into the early formation and accretion history of the Milky Way (MW). Here, we use five high-resolution cosmological zoom-in simulations (∼ 5 × 106 star particles) of MW-like galaxies taken from the NIHAO-UHD project, to investigate the origin of low-metallicity stars ([Fe/H] ≤ −2.5). The simulations show a prominent population of low-metallicity stars confined to the disc plane, as recently discovered in the MW. The ubiquity of this finding suggests that the MW is not unique in this respect. Independently of the accretion history, we find that ≳90 per cent of the retrograde stars in this population are brought in during the initial build-up of the galaxies during the first few Gyr after the Big Bang. Our results therefore highlight the great potential of the retrograde population as a tracer of the early build-up of the MW. The prograde planar population, on the other hand, is accreted during the later assembly phase and samples the full galactic accretion history. In case of a quiet accretion history, this prograde population is mainly brought in during the first half of cosmic evolution (t ≲ 7 Gyr), while, in the case of an ongoing active accretion history, later mergers on prograde orbits are also able to contribute to this population. Finally, we note that the MW shows a rather large population of eccentric, very metal-poor planar stars. This is a feature not seen in most of our simulations, with the exception of one simulation with an exceptionally active early building phase.

The First Galaxies in the Universe

2013 ◽  
Author(s):  
Abraham Loeb ◽  
Steven R. Furlanetto
Keyword(s):  
Galaxy Evolution ◽  
Big Bang ◽  
First Stars ◽  
Distant Galaxies ◽  
Formation And Evolution ◽  
Early Galaxies ◽  
First Galaxies ◽  
Large Telescopes ◽  
New Generation ◽  
The Big Bang

This book provides a comprehensive, self-contained introduction to one of the most exciting frontiers in astrophysics today: the quest to understand how the oldest and most distant galaxies in our universe first formed. Until now, most research on this question has been theoretical, but the next few years will bring about a new generation of large telescopes that promise to supply a flood of data about the infant universe during its first billion years after the big bang. This book bridges the gap between theory and observation. It is an invaluable reference for students and researchers on early galaxies. The book starts from basic physical principles before moving on to more advanced material. Topics include the gravitational growth of structure, the intergalactic medium, the formation and evolution of the first stars and black holes, feedback and galaxy evolution, reionization, 21-cm cosmology, and more.

The Planet in a Pebble

2010 ◽  
Author(s):  
Jan Zalasiewicz
Keyword(s):  
Solar System ◽  
Volcanic Eruptions ◽  
Big Bang ◽  
Forensic Analysis ◽  
Mineral Matter ◽  
Supernova Explosions ◽  
Deep Underground ◽  
The Big Bang ◽  
The Universe

This is the story of a single pebble. It is just a normal pebble, as you might pick up on holiday - on a beach in Wales, say. Its history, though, carries us into abyssal depths of time, and across the farthest reaches of space. This is a narrative of the Earth's long and dramatic history, as gleaned from a single pebble. It begins as the pebble-particles form amid unimaginable violence in distal realms of the Universe, in the Big Bang and in supernova explosions and continues amid the construction of the Solar System. Jan Zalasiewicz shows the almost incredible complexity present in such a small and apparently mundane object. Many events in the Earth's ancient past can be deciphered from a pebble: volcanic eruptions; the lives and deaths of extinct animals and plants; the alien nature of long-vanished oceans; and transformations deep underground, including the creations of fool's gold and of oil. Zalasiewicz demonstrates how geologists reach deep into the Earth's past by forensic analysis of even the tiniest amounts of mineral matter. Many stories are crammed into each and every pebble around us. It may be small, and ordinary, this pebble - but it is also an eloquent part of our Earth's extraordinary, never-ending story.

scholarly journals FRONTIER RESEARCH IN ASTROPHYSICS IN THE GRAVITATIONAL WAVE ERA - II(EXOPLANETS AND EMERGENCE OF LIFE)

2021 ◽  
Vol 53 ◽  
pp. 235-244
Author(s):  
L. Sabau-Graziati ◽  
F. Giovannelli
Keyword(s):  
Gravitational Wave ◽  
Milky Way ◽  
Big Bang ◽  
Habitable Zone ◽  
Terrestrial Life ◽  
The Big Bang ◽  
Emergence Of Life

In this paper we will discuss exoplanets in the habitable zone of the Milky Way, the origin of terrestrial life, and what 'intelligent' humanity is doing, in order to complete the excursion on <i>The Bridge between the Big Bang and Biology</i>, started with the paper I (Giovannelli & Sabau-Graziati, 2020).

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 The Radiation-Dominated Universe in Nonstandard Cosmology

2020 ◽  
Vol 5 (4) ◽  
Author(s):  
Günter Scharf ◽  
Keyword(s):  
Evolution Equations ◽  
Big Bang ◽  
The Other ◽  
Spherically Symmetric ◽  
Velocity Perturbation ◽  
Model Universe ◽  
Cosmic Evolution ◽  
Big Crunch ◽  
The Big Bang ◽  
Irregular Singular Points

We continue the recent study of our model theory of low-density cosmology without dark matter. We assume a purely radiative spherically symmetric background and treat matter as anisotropic perturbations. Einstein’s equations for the background are solved numerically. We find two irregular singular points, one is the Big Bang and the other a Big Crunch. The radiation temperature continues to decrease for another 0.21 Hubble times and then starts to increase towards infinity. Then we derive the four evolution equations for the anisotropic perturbations. In the Regge- Wheeler gauge there are three metric perturbations and a radial velocity perturbation. The solution of these equations allow a detailed discussion of the cosmic evolution of the model universe under study.

The First Stars

2013 ◽  
Author(s):  
Abraham Loeb ◽  
Steven R. Furlanetto
Keyword(s):  
Phase Transition ◽  
Early Universe ◽  
Galaxy Formation ◽  
Big Bang ◽  
First Stars ◽  
Complex Chemical ◽  
Radiative Processes ◽  
Complex Processes ◽  
The Big Bang ◽  
The Universe

This chapter considers the emergence of the complex chemical and radiative processes during the first stages of galaxy formation. It studies the appearance of the first stars, their feedback processes, and the resulting ionization structures that emerged during and shortly after the cosmic dawn. The formation of the first stars tens or hundreds of millions of years after the Big Bang had marked a crucial transition in the early Universe. Before this point, the Universe was elegantly described by a small number of parameters. But as soon as the first stars formed, more complex processes entered the scene. To illustrate this, the chapter provides a brief outline of the prevailing (though observationally untested) theory for this cosmological phase transition.

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