★★★★★
Synopsis: Humans are now virtualized, and can materialize in any wished form. One suche colony sends out their clones on a mission to find life in the galaxy and to proof their understatement that the universe was NOT created solely for mankind. The main protagonist’s voyage leads to planet Orpheus, circling the star Vega, finding life in form of large carpets in the ocean. A longer discussion between “wait for a couple millenia” or “risk the danger of contamination for a closer analysis” leads to the vote for researching those carpets using nanobots. First finding is that they happen to be a single long carbohydrate molecule which doesn’t qualify as intelligent life. But then, one of the scientists finds out, that those carpets build an equivalent to Turing machines using the theory of Wang’s tiles (with each carpet being one tile) building effectively a kind of computer or brain.
Review: The author included the novelette as part of his novel Diaspora. It is a brillant piece of Hard SF in a posthuman universe that might be categorized as MathFiction. The philosophical and mathematical debates are probably hard to get for people outside of theoretical computer science (and would be worth one or two stars less). As my specialized field of study once was exactly that theory, I just felt at home and found it mind-blowing how the author applied the theory to a first contact story. I praise it just for the genius application of the idea and its discussion in posthuman communities, disregarding its lack of action or character evolvement.
Meta: isfdb.
Reißwolf 
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