Dyson sphere

A heartfelt tribute to Freeman Dyson

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(...) Dyson is too modest.
Richard Carrigan⁽⁸⁾

The search for extraterrestrial life has, as I already written, some illustrious founding fathers: Enrico Fermi and his paradox; Giuseppe Cocconi and Philip Morrison and their 1959 proposal to use radio astronomy to search for extraterrestrial signals of intelligent origin⁽¹⁾; Frank Drake with his famous equation, and therefore with the Ozma project⁽²⁾, so called for the queen of the imaginary land of Oz, a very distant place, difficult to reach and populated by exotic beings, a kind of proto-SETI, project that Drake helped to found and launch.
Another important contribution to the quest of intelligent signal in the universe come from Freeman Dyson^{(3, 8)}:

If extraterrestrial intelligent beings exist and have reached a high level of technical development, one by-product of their energy metabolism is likely to be the large-scale conversion of starlight into far-infrared radiation. It is proposed that a search for sources of infrared radiation should accompany the recently initiated search for interstellar radio communications.⁽³⁾

Dyson, taking our solar system as a model, observed how the mass of Jupiter, if distributed with spherical symmetry on a double orbit compared to that of the Earth, would have been 2 tons per square meter thick:

A shell of this thickness could be made comfortably habitable, and could contain all the machinery required for exploiting the solar radiation falling onto it from the inside⁽³⁾

Turing and the ecological basis of morphogenesis

about #AlanTuring #morphogenesis #ecology

It is recently published a paper (in open access) dedicated to the morphogenesis. The work (and the model) is inspired by Alan Turing:

Our results demonstrate that a simple model implementing counteracting processes acting on different length-scales can indeed recreate branching patterns similar to those of swarming colonies. The kernel-based phenomenological model presented here draws from ecological theory, which has long recognized the relevance of distance-dependent processes as drivers for spatial patterning (Levin 1992). Many concepts from patterning in ecology are intimately related with the chemical basis of morphogenesis first proposed by Turing (1952), who first explained that counteracting positive and negative chemical processes acting on different length-scales can lead to symmetry-breaking that triggers biological patterning (Morelli et al 2012). The model presented here is inspired by Turing's findings but uses the spatial kernel approach of recent population ecology models (e.g. Rietkerk et al 2004, Lindstrom et al 2011) rather than reaction–diffusion processes.

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Pan Deng, Laura de Vargas Roditi, Dave van Ditmarsch, Joao B Xavier (2014). The ecological basis of morphogenesis: branching patterns in swarming colonies of bacteria New Journal of Physics, 16 (1), 1-16 DOI: 10.1088/1367-2630/16/1/015006

Earlth and Moonch

This beautiful shot (via Universe Today) is the Cygnus Constellation. The photographer is Marco T., italian, and you can see others great photos on his flickr account.
But this beautiful shot is the better introduction to Earlth and Moonch, a animated short by Dei Gaztelumendi I see the short in Italy, during the Milano Film Festival, and in the worlds of Gaztelumendi is a reflession about Earth, ecology and our future.