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Cosmic Darwinism

  1. Aug 18, 2009 #1
    Can someone please sum up "Cosmic Darwinism" for me? I've looked on search engines and I can't seem to find anything.
     
  2. jcsd
  3. Aug 18, 2009 #2

    marcus

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    Ideas in science mature and develop as more people get involved in working on them, so if I just tell you what I think is the original way it came into discussion that won't completely cover the topic.

    Around 1992 Smolin posted one or two papers about cosmological natural selection (CNS) and then around 1998 or a book of his about CNS appeared called The Life of the Cosmos.

    You might find more hits using "cosmological natural selection". AFAIK the term "cosmic darwinism" is much more recent. Smolin is just beginning to use that term as a synonym for CNS. And other people are interested, and have their own ideas, and they may in time start using the term in other ways.
    Language bears some resemblance to an arena. Words don't have fixed meanings carved in stone.

    The original CNS idea may actually go back to the princeton physicist John Wheeler (he was Feynman's PhD mentor/advisor). But the first papers specifically about it were Smolin's 1992.
    The idea is very simple. If stellar collapse leading to black hole formation is a reproductive mechanism by which a new episode of space expansion can get started, with a kind of bounce, and if the rules of behavior of geometry and matter which are inherent in the fabric of existence can get slightly altered during the bounce, then spacetime regions will be selected for reproductive success and after a few generations almost all you will have are regions which are good at reproducing themselves.

    So if those two assumptions are true, the typical spacetime region will have embedded in its fabric rules for how geometry and matter behave that make for a lot of stars, and of those stars a substantial proportion will collapse to hole. The numerical physical constants (ratios of masses, forces, determinants of nuclear and chemical reactions, stable elements etc.) will be optimized---they will appear to be fine-tuned for hole abundance.

    This of course seems very bizarre. One would not expect the constants of nature to be finetuned for anything, why should anything be maximized.

    Except of course birds and animals are in some sense optimized for doing whatever they do. For filling whatever niche. In another context it isn't so bizarre.

    Now we could lay this to rest if we could just find some physical parameter which is NOT optimized for making a world with plenty of stars that then often collapse to hole. That would tend to discredit the two assumptions I mentioned (about reproduction with slight variation in the laws) and would tend to kill off the Cosmic Darwinism idea.

    I think that, in brief, is where it stands now.
     
    Last edited: Aug 18, 2009
  4. Aug 18, 2009 #3

    marcus

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    I think the best free online thing to read about it is this:
    http://arxiv.org/abs/hep-th/0407213

    Or rather parts of that paper, not the whole thing, maybe skip the first 20 pages or so. Skip to wherever he starts talking about CNS.
     
  5. Aug 19, 2009 #4

    Chronos

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    Living things are merely chemical processes optimized to function under conditions that currently exist on earth. I think it is reasonable to assume similar processes have, do and will eventually arise elsewhere in the universe. In a 'multiverse' this is inevitable. But, it is not necessary or reasonable to assume any particular universe is obliged to encourage such processes.
     
  6. Aug 19, 2009 #5
    To piggy back on Marcus's post a bit I would add that the hypothesis of CNS is presented as an alternative to The Anthropic Principle (AP). AP, as I understand it, suggests there are many (possibly infinite) universes, causally disconnected from our own. The values of the standard models differ from universe to universe and are generated at random so that the parameters for the universe we live in are rare and in a sense, the result of chance. This is in contrast to the causal connection between black hole births and "fine tuning" of the standard model parameters.

    From what I’ve ascertained in studying and discussing these subjects, Loop Quantum Gravity (LQG) proponents (like Lee Smolin) tend to lean toward Cosmic Natural Selection (IMO the term Cosmic Darwanism is an attempt to gain unearned credibility from casual observers by equating CNS with settled scientific fact) while string theory proponents (like Leonard Susskind) tend to support AP.

    It looks as though should CNS proves true then String Theory is eliminated as a contender for the Theory of Everything solution and the same holds for LQG if AP is proven. Which ever emerges out of this endeaver, I suspect CNS or AP will become THE identifying principle for the framework in the way The Uncertainty Principle has for Quantum Theory.

    I hope that adds some context for you.
     
  7. Aug 26, 2009 #6
    I hope this helps you. :smile:
    From NASA - ASTROBIOLOGY Magazine

     
  8. Aug 26, 2009 #7

    marcus

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    Be careful, the article Views just linked to does not talk about Cosmic Darwinism or even use those words! It does not say those words and it does not talk about the ideas that come under the heading in professional writing.

    It appears to be written by a science outreach journalist, who uses inappropriate wording like
    galactic darwinism, and cosmic evolution---which were not used by the scientists themselves, whose work the journalist is hyping up---this can easily confuse people.
    Better not to use journalist's language if you can help it. Even the professional scientists can be sloppy themselves sometimes---have to be prepared to have words used to mean two entirely different things. But they are not usually as sloppy as the PR journalists writing for public consumption.

    The article Views linked to says it is based on this Press Release from the ESO
    http://www.eso.org/public/outreach/press-rel/pr-2006/pr-45-06.html [Broken]

    You can see from the URL that it is "public outreach". Public relations departments often unreliable. But even this does not use the word "cosmic".
    It is strictly talking about galaxies and how they develop over time.

    The "public outreach" copy was in turn derived from this scientific paper:
    http://www.aanda.org/index.php?opti...cles/aa/full/2006/40/aa5161-06/aa5161-06.html
    As far as I can tell IN THE ACTUAL PAPER IT DOES NOT SAY DARWIN OR DARWINIAN. It talks about the time-evolution of galaxies. Systems evolve with time. Galaxies are tiny things compared with the universe. Like other systems, galaxies evolve with time.

    A PDF of the article is available here:
    http://arxiv.org/abs/astro-ph/0603202

    Nothing in this article is connected with our topic of Cosmic Darwinism. A bad case of a PR journalist using confusing language----maybe a little intentional hype to spice up otherwise not very interesting press release.

    Always track outreach articles back to the original professional publication source, if you can, and see what the guys are actually saying. Please!
     
    Last edited by a moderator: May 4, 2017
  9. Aug 27, 2009 #8
    Marcus, I was giving an answer to the OP as noted. Also, I would appreciate you calling me Mars in the future. Mars is my nickname and I have in another topic to you thanked you with my nickname as you obviously have forgotten.

    You said, "Nothing in this article is connected with our topic of Cosmic Darwinism." I don't think you have the right to dictate or answer for the OP (Nickriener) who was in search of information. I have the right to disagree with you. By the way, the article is from ASTROBIOLOGY Magazine which notes at the top of the page that it is linked to NASA. Also, a picture to the left of the page of the link I gave states under the picture: All life on Earth (that we know of) has a similar DNA-based chemistry. Credit: NASA

    In all fairness I think we can agree to disagree on this topic. :-) The OP has left us open to discuss his/her question. He/she has not returned with any further comments so I think that I can also provide an answer since we don't really know where he/she may have gotten this "cosmic darwinism" from off the Internet if you get my drift. (I've read about it elsewhere on a site that wasn't about science.)
     
    Last edited by a moderator: May 4, 2017
  10. Aug 27, 2009 #9
    Professor Eric J. Chaisson is Director of Wright Center for Science Education. He is a Research Professor of Physics and Astronomy of Tufts University, a Research Professor of Education for Tufts University, an Associate, Harvard College Observatory, Harvard University and an affiliate-director, Massachusetts Space Grant Consortium, (1992-2008) MIT.

    Professor Chaisson has a wonderful on-line tutorial that should be helpful in answering
    question(s). Wright Center for Science Education - Cosmic Evolution:smile:
    http://www.tufts.edu/as/wright_center/cosmic_evolution/docs/splash.html [Broken]
     
    Last edited by a moderator: May 4, 2017
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