18 March 2012

Between two worlds

Jürgen Schmidhuber may be right that creative machines will overtake humans within a few decades. Certainly, to engage with this even as possibility demands a lot of the imagination. [1]

I'd only like to add right that, whatever the future may hold, in trying to right-size our imaginations to the dimensions of the present moment and the possible future, it's also important to develop our comprehension of the deep past.  A book by Callum Roberts to be published in May 2012 will help with this.

Roberts's chief concern in The Ocean of Life is with the (almost entirely destructive) human impacts on the world ocean over the last fifty years -- less than a thousandth of the 150 to 200,000 years for which modern humans have existed.  His introductory chapter, however, covers the first 4.5 billion years.

One of the things Roberts does exceptionally well in it is to pull together an account of major events in the Earth system during the first 4 billion of those years: the Hadean, Archaean and Proterozoic eons.  There is nothing original in the material itself -- the author is summarizing published research that has also been marshaled in other books and art works for non-specialists [2]  -- it's just that he does a very good job of helping the reader to 'inhabit' this time/space in his or her own mind. Consider, for example:
...About 4.53 billion years ago a planet the size of Mars barreled into this new world and smashed off pieces that became the moon. The impact was so enormous it vapourised rock and the primeval world was shrouded by a thick atmosphere of rock and other gases. As the planet cooled, a time came when minerals condensed and for two thousand years the skies rained molten rock onto an ocean of magma below. Even after this thousand degree deluge ended, the atmosphere remained thick with other vapour and gases and atmospheric pressure at the surface of the flaming sea would have been hundreds of times higher than today. 
We owe a lot to this collision. It knocked Earth’s axis of rotation askew, which gives us seasons . Over the vast plain of geological time, the moon has slowed and stabilized the Earth’s rotation, giving us longer days. A billion years ago, a day was just 18 hours and the year lasted 480 days. Early on, the moon was much closer to Earth and would have loomed large in the sky. The moon’s gravitational pull gives us much greater tides than the more distant sun alone and the flood and ebb of tides would have been violent as they rose higher and fell faster in the short days...
...When the Earth cooled down a bit, a new rain began to fall, this time of scalding water. The downpour lasted for thousands of years and would be repeated several times over the next half billion years as giant impacts from extraterrestrial debris boiled off the upper layers of the seas. For a half billion years more, the Earth continued to be struck by asteroids far bigger than the one that killed off the dinosaurs 65 million years ago... 
...To begin with, oceans covered most of the world. Their volume could have been twice that of the present seas. Islands cropped up where blocks of the Earth’s crust collided and volcanoes built ash and lava mountains, but there were no continents. Those came later and formed slowly...
Even if one is familiar to some extent with these facts it is, I think, really valuable to have them brought to mind. On each iteration of learning and re-imagining we gain and appreciate a bit more.  Perhaps they can help us to become better ancestors. [3]

Florian Imgrund

[1] The fact that the prospect is unprecedented and so may seem intuitively unlikely to ignoramuses like me is not in itself evidence that it is in fact unlikely. See Intelligence Explosion: Evidence and Import. I'll be impressed when a computer creates music greater than anything by Bach, Beethoven or Chopin. Then again, I probably won't be able to appreciate it. [Added 1 April. Marcus du Sautoy writes:
Exciting new research is currently exploring how creative machines can be in music and art. Stravinsky once wrote that he could only be creative by working within strict constraints: "My freedom consists in my moving about within the narrow frame that I have assigned myself for each one of my undertakings." By understanding the constraints that produce exciting music, computer engineers at Sony's Computer Science Laboratory in Paris are beginning to produce machines that create new and unique forms of musical composition.]
[2]  Terrence Malick's The Tree of Life touches on some of these events in the cosmic-creation sequences of the film.  These are remarkable but they have no commentary: we need verbal accounts to build a full picture.

[3] Schmidhuber's advice is that we should be content to regard ourselves as a small stepping stone on the path to a more complex [and beautiful?] universe.

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