Are We Alone in the Universe?

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Science  01 Jul 2005:
Vol. 309, Issue 5731, pp. 88
DOI: 10.1126/science.309.5731.88

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  • SETI, evolution and time

    The answer to the question “Are we alone?” might depend on two things which everyone seems to be overlooking – 1) evolution not being responsible for the origin of life, and 2) time.

    Evolution can be observed in the form of adaptation of structure and function to the environment but there’s no reason to extrapolate this so it accounts for life’s origin. In future centuries, human technology will develop terraforming and incredibly advanced genetic engineering of amino acids etc which were gathered in space or on planets and combined. This could account for life’s origin since it agrees with Louis Pasteur’s proving that life can only originate from life (modern science’s obsession with abiogenesis should take note of Pasteur).

    There might then be no other life (on other planets) at present. When humans explore the universe, they could cause life – even technological intelligences – to emerge elsewhere. Development of time travel would allow these intelligences to exist not only in our future but also in our past ... and yes, in our present.

    Competing Interests: None declared.
  • weak answer

    "The universe is big, so there's got to be life out there." That's the best you can do? I love this issue of Science, but that's a weak answer to this question.

    I admit I am stunned and surprised by the silence we've experienced. But we've listened to enough of the "audible" universe that we should have heard something if there were something to hear (I presume that other intelligent life would ask the same quest...

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    Competing Interests: None declared.
  • Flaw in Logic

    Kerr's enthusiastic report on SETI and the search for "life" elsewhere in the Universe is logically flawed. Why does he assume that the probability of finding conditions leading to life-as-on-Earth has anything to do with terrestrial statistics?

    Competing Interests: None declared.
  • endless permutations

    I had long assumed that with some 10 to the 23 or 24 star systems in the universe, it was likely that intelligent life forms should also exist elsewhere. On reflection, I now doubt it: Over the last four plus billion years, we have gone through endless random permutations before the first living organism appeared, then we went through endless mutations, not to mention inumerable species extinctions, to arrive at our curr...

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    Competing Interests: None declared.
  • We Must Put Time In the Equation

    In his exposition of the probability of finding other intelligent life in the universe, Richard Kerr points to the enormous numbers of potential planets, which he concludes makes it only a matter of time before the evidence of such life is uncovered. But he ignores the very parameter, time, which may severely limit the number of candidate planets inhabited by such life.

    In round numbers, it has taken some 15 bi...

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    Competing Interests: None declared.
  • Show Me the Numbers

    To justify the OZMA project, Frank Drake proposed a simple formula for computing the probability of intelligent life elsewhere in the Milky Way. How should that formula be recast today in light of new knowledge in biology and astronomy? Has the probability gone up or gone down? From the latest data about the proclivity of gas giant planets to migrate inward toward their stars, one would wonder if many terrestrial planets...

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    Competing Interests: None declared.
  • SETI : Is it looking in the right direction?

    The project SETI makes a rather restrictive assumption that intelligent life-forms if any, will develop over time to invent means of communication using radio waves. A glance at the biosphere should indicate all life-forms other than man have never made an attempt to do so. The same might hold true in the future also.

    The vastness of the universe suggests a strong possibility of the presence of other places hosp...

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    Competing Interests: None declared.

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