La respuesta de los «conservadores» […] parece reflejar el esquema clásico de reacción inducido por las novedades científicas: no es cierto (primera fase); aunque sea cierto, es una cuestión secundaria (segunda fase); es cierto, pero yo ya lo había dicho (tercera fase).
Telmo PievaniRepensar a Darwin, Investigación y Ciencia, enero 2016
Evolution has no destination. Each time you push the «go» button, you end up someplace different. Start things over on Earth (or another Earth-like planet) and not only would there be different species with perceptions and intelligences that vary wildly from our own, the very chemistry of life would be altered as well!
That’s conjecture – but it’s pretty safe conjecture. To see why, let’s do a quick back-of-the-envelope calculation.
Among other things, our DNA contains instructions for building proteins out of sequences of amino acids. For simplicity, let’s assume that life always evolves that same basic molecular machinery. There are 500 or so known amino acids, of which life on Earth uses only 23. Sticking with our KISS (keep it simple, stupid) approach, let’s assume all life uses those same 23.
The average protein in an eukaryotic (nucleus-containing) cell on Earth is about 450 amino acids long. There are therefore 23^450 (=10^613) different proteins of that length that the machinery of our DNA might construct. That’s a huge number! Not surprisingly, terrestrial life has stumbled upon uses for only a small fraction of those possible proteins – about 10 million.
So now let’s take those 10^613 possible proteins and split them into planet-proportioned groups of 10 million each. With no overlap at all, there would be 10^606 of those piles! There are no more than about 10^23 habitable planets in the entire observable universe. You could spread those stacks of proteins over the planets in 10^583 similar universes without having to duplicate a single protein on any two planets!
The takeaway is this: The likelihood that any two life-bearing planets in the universe share even remotely compatible biochemistry is effectively zero.
Jeff Hester. Astronomy Magazine, September 2016
The welfare of the earth and its inhabitants is a defining theme for the 21st century. Structural engineering has a significant role to play as the world faces these challenges. In fulfilling this function, building engineers continue the age-old human endeavor to provide society with structures that protect, serve, and inspire mankind. From pioneering new systems for better buildings with economy, to ensuring the safety of human life from nature’s wrath, to stabilizing implausible forms to defy gravity and lateral loads, building engineers venture to create livable spaces from humaninity’s dreams and ideas. Building engineering requires a comprehensive understanding of building assembly and an appreciation of how forces are resisted within the structure and eventually by the earth.
Bungale S. Taranath, «Structural Analysis and Design of Tall Buildings. Steel and Composite Construction». CRC Press, Boca Raton, 2012
On seismic design:
Although over the years, experience and research have diminished our uncertainties and concerns regarding the characteristics of earthquake motions and its manifestations, it is unlikely, though, that there will be such a change in the nature of knowledge to relieve us of the necessity of dealing openly with random variables. In a way, earthquake engineering is a parody of other branches of engineering. Earthquake effects on structures systematically bring out the mistakes made in design and construction, even the minutest mistakes. Add to this the undeniable dynamic nature of disturbances, the importance of soil-structure interaction and the extremely random nature of it all; it could be said that earthquake engineering is to the rest of the engineering disciplines what psychiatry is to other branches of medicine. This aspect of arthquake engineering makes it challenging and fascinating, and gives it an educational value beyond its inmediate objectives. If structural engineers are to acquire fruitful experience in a brief span of time, expose them to the concepts of earthquake engineering, even if their interest in earthquake-resistant design is indirect. Sooner or later, they will learn that the difficulties encountered in seismic design are technically intriguing and begin to exercise that nebulous trait called engineering judgment to make allowance for these unknown factors.
Bungale S. Taranath, «Structural Analysis and Design of Tall Buildings. Steel and Composite Construction». CRC Press, 2012, Boca Raton, Florida.
On two occasions I have been asked (by members of Parliament!), «Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?» I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question.
Charles Babbage (1791-1871), diseñador de la máquina analítica, precursora del ordenador.
Inventors and Inventions, Volume 1. Marshall Cavendish, 2007