Related papers: On The Timescale Forcing in Astrobiology
It is well known that no time-independent galactic cosmic ray (GCR) flux model can account for the observed linear relationship of Be and B abundances with metallicity. In this contribution we solve the time-dependent CR propagation…
We present a model of the Galactic Habitable Zone (GHZ), described in terms of the spatial and temporal dimensions of the Galaxy that may favour the development of complex life. The Milky Way galaxy is modelled using a computational…
When searching for inhabited exoplanets, understanding the boundaries of the habitable zone around the parent star is key. If life can strongly influence its global environment, then we would expect the boundaries of the habitable zone to…
We discuss possible tests of the constancy of the velocity of light using distant astrophysical sources such as gamma-ray bursters (GRBs), Active Galactic Nuclei (AGNs) and pulsars. This speculative quest may be motivated by some models of…
Determining planetary habitability is a complex matter, as the interplay between a planet's physical and atmospheric properties with stellar insolation has to be studied in a self consistent manner. Standardized atmospheric models for…
Cosmic rays can penetrate planetary atmospheres driving the formation of prebiotic molecules, which are important for the origin of life. We calculate the Galactic cosmic ray fluxes in the habitable zone of five nearby, well-studied…
We study the power density spectrum (PDS) of light curves of the observed gamma-ray bursts (GRBs) to search for a direct signature for cosmological time dilation in the PDS statistics with the GRBs whose redshifts $z$'s are known. The…
Recent stellar evolution models for globular clusters (GCs) in multiple population paradigm suggest that horizontal-branch (HB) morphology and mean period of type ab RR Lyrae variables are mostly determined by He & CNO abundances and…
Human influence on the biosphere has been evident at least since the development of widespread agriculture, and some stratigraphers have suggested that the activities of modern civilization indicate a geological epoch transition. The study…
It is often presumed, that life evolves relatively fast on planets with clement conditions, at least in its basic forms, and that extended periods of habitability are subsequently needed for the evolution of higher life forms. Many planets…
Energetic particles, such as stellar cosmic rays, produced at a heightened rate by active stars (like the young Sun) may have been important for the origin of life on Earth and other exoplanets. Here we compare, as a function of stellar…
Civilization cannot sustain an exponential growth for long time even when neglecting numerous laws of physics! In this paper, we examine what are fundamental obstacles to long term survival of a civilization and its possibility to colonize…
We illuminate the altered evolution of galaxies in clusters compared to the field by tracking galaxies in the IllustrisTNG300 simulation as they enter isolated clusters of mass $10^{13} < M_{\rm 200, mean} / {\rm M}_\odot < 10^{15}$ (at…
The search for extraterrestrial intelligence (SETI) has been heavily influenced by solutions to the Drake Equation, which returns an integer value for the number of communicating civilisations resident in the Milky Way, and by the Fermi…
Temporal correlations of time series or event sequences in natural and social phenomena have been characterized by power-law decaying autocorrelation functions with decaying exponent $\gamma$. Such temporal correlations can be understood in…
In a multiverse context, determining the probability of being in our particular universe depends on estimating its overall habitability compared to other universes with different values of the fundamental constants. One of the most…
Gamma-ray Bursts (GRBs) are relativistic cosmological beacons of transient high energy radiation whose afterglows span the electromagnetic spectrum. Theoretical expectations of correlated neutrino emission position GRBs at an astrophysical…
The galactic habitable zone is defined as the region with sufficient abundance of heavy elements to form planetary systems in which Earth-like planets could be born and might be capable of sustaining life, after surviving to close supernova…
Earth will become uninhabitable within 2-3 Gyr as a result of the moving boundaries of the habitable zone caused by the increasing luminosity of the Sun. Predictions about the future of habitable conditions on Earth include a decline in…
We present in this work a unified, quantitative synthesis of analytical and numerical calculations of the effects that could be caused on Earth by a Gamma-Ray Burst (GRB), considering atmospheric and biological implications. The main…