Related papers: Relative Likelihood for Life as a Function of Cosm…
I examine some recent findings in cosmology and their potential implications for the emergence of life in the universe. In particular, I discuss the requirements for carbon-based life, anthropic considerations with respect to the nature of…
It is sometimes asserted that the rapidity of biogenesis on Earth suggests that life is common in the Universe. We critically examine the assumptions inherent in this argument. Using a lottery model for biogenesis in the Universe, we…
A habitable zone of a star is defined as a range of orbits within which a rocky planet can support liquid water on its surface. The most intriguing question driving the search for habitable planets is whether they host life. But is the age…
The aim of this paper is to underline conditions necessary for the emergence and development of life. They are placed at local planetary scale, at Galactic scale and within the cosmological evolution, as pointed out by the Anthropic…
We present observational evidence of environmental effects on the formation and evolution of planetary systems. We combine catalogues of resolved protoplanetary discs (PPDs) and young stellar objects in the solar neighbourhood to analyse…
The data recently accumulated by the Kepler mission have demonstrated that small planets are quite common and that a significant fraction of all stars may have an Earth-like planet within their Habitable Zone. These results are combined…
I attempt to piece together a consistent scenario based on current estimates of the evolution of the star formation rate of the Universe, the metallicity evolution of the star-forming regions of the Universe and the most recent observations…
The transformation of organic molecules into the simplest self-replicating living system,a microorganism, is accomplished from a unique event or rare events that occurred early in the Universe. The subsequent dispersal on cosmic scales and…
In this article, we attempt to convince the reader that the origin of life was such an exceptionally unlikely event that it probably has never occurred elsewhere. This involves an explicit calculation using the laws of physics which, while…
The existence of intelligent, interstellar traveling and colonising life is a key assumption behind the Fermi Paradox. Until recently, detecting signs of life elsewhere has been so technically challenging as to seem almost impossible.…
The habitable zone is the circumstellar region in which a terrestrial-mass planet with an atmosphere can sustain liquid water on its surface. However, despite the usefulness of this concept, it is being found to be increasingly limiting in…
I discuss recent theoretical work on the formation and evolution of galaxies paying particular attention to the ability of current models to make detailed comparisons with observations of the galaxy population both nearby and at high…
Smaller terrestrial planets (< 0.3 Earth masses) are less likely to retain the substantial atmospheres and ongoing tectonic activity probably required to support life. A key element in determining if sufficiently massive "sustainably…
I describe a new method of estimating the prevalence of life in the Universe, based on the fact that more chemically complex environments are more rare. The paper makes three main claims: (1) There is a statistically significant (inverse)…
We modeled the evolution of the Milky Way to trace the distribution in space and time of four prerequisites for complex life: the presence of a host star, enough heavy elements to form terrestrial planets, sufficient time for biological…
A key result of hydrogravitational dynamics cosmology relevant to astrobiology is the early formation of vast numbers of hot primordial-gas planets in million-solar-mass clumps as the dark matter of galaxies and the hosts of first life.…
There is growing evidence that brown dwarfs may be comparable to main-sequence stars in terms of their abundance. In this paper, we explore the prospects for the existence of life on Earth-like planets around brown dwarfs. We consider the…
A series of astronomical observations obtained over the period 1986 to 2018 supports the idea that life is a cosmic rather than a purely terrestrial or planetary phenomenon. These include (1) the detection of biologically relevant molecules…
Understanding the concept of habitability is related to an evolutionary knowledge of the particular planet-in-question. Additional indications so-called "systemic aspects" of the planetary system as a whole governs a particular planet's…
Current evidence suggests that the cosmological constant is not zero, or that we live in an open universe. We examine the implications for the future under these assumptions, and find that they are striking. If the Universe is cosmological…