The habitable epoch of the early Universe
نویسنده
چکیده
In the redshift range 100 ,(1+z) ,137, the cosmic microwave background (CMB) had a temperature of 273–373 K (0–100 °C), allowing early rocky planets (if any existed) to have liquid water chemistry on their surface and be habitable, irrespective of their distance from a star. In the standardΛCDM cosmology, the first star-forming halos within our Hubble volume started collapsing at these redshifts, allowing the chemistry of life to possibly begin when the Universe was merely 10–17 million years old. The possibility of life starting when the average matter density was a million times bigger than it is today is not in agreement with the anthropic explanation for the low value of the cosmological constant. Received 27 February 2014, accepted 3 June 2014
منابع مشابه
A meshless discrete Galerkin method for solving the universe evolution differential equations based on the moving least squares approximation
In terms of observational data, there are some problems in the standard Big Bang cosmological model. Inflation era, early accelerated phase of the evolution of the universe, can successfully solve these problems. The inflation epoch can be explained by scalar inflaton field. The evolution of this field is presented by a non-linear differential equation. This equation is considered in FLRW model...
متن کاملOn the Habitability of Our Universe
Is life most likely to emerge at the present cosmic time near a star like the Sun? We consider the habitability of the Universe throughout cosmic history, and conservatively restrict our attention to the context of “life as we know it” and the standard cosmological model, ΛCDM. The habitable cosmic epoch started shortly after the first stars formed, about 30 Myr after the Big Bang, and will end...
متن کامل1 Habitable Zones in the Universe
Habitability varies dramatically with location and time in the universe. This was recognized centuries ago, but it was only in the last few decades that astronomers began to systematize the study of habitability. The introduction of the concept of the habitable zone was key to progress in this area. The habitable zone concept was first applied to the space around a star, now called the Circumst...
متن کاملStructure formation and generalized second law of thermodynamics in some viable f(R)-gravity models
We investigate the growth of matter density perturbations as well as the generalized second law (GSL) of thermodynamics in the framework of f(R)-gravity. We consider a spatially flat FRW universe filled with the pressureless matter and radiation which is enclosed by the dynamical apparent horizon with the Hawking temperature. For some viable f(R) models containing the Starobinsky, Hu-Sawicki, Exp...
متن کاملPrimordial Black Holes as a Probe of the Early Universe and a Varying Gravitational Constant
We discuss recent developments in the study of primordial black holes, focussing particularly on their formation and quantum evaporation. Such studies can place important constraints on models of the early Universe. An especially interesting development has been the realization that such constraints may be severely modified if the value of the gravitational “constant” G varies with cosmological...
متن کامل