ADVERTISEMENT
  About the SA Blog Network













Guest Blog

Guest Blog


Commentary invited by editors of Scientific American
Guest Blog HomeAboutContact

The Logic and Beauty of Cosmological Natural Selection

The views expressed are those of the author and are not necessarily those of Scientific American.


Email   PrintPrint



I have a prediction. There is a scientific hypothesis, formulated over 20 years ago, that we will one day look back on, when the evidence is in, and say “Of course that was right! What a spectacularly powerful idea!”

The hypothesis is cosmological natural selection, and its power, beauty and logic provide what may be the best scientific explanation for the existence of complexity and life in the universe.

The explanatory power of cosmological natural selection directly addresses, rather than ignores, one of the very deepest fundamental scientific mysteries. If the laws and parameters of nature’s particles and forces were even just a little bit different, the formation life would be impossible. If the ratio of electrons to protons, the expansion rate of the universe, the relative masses of elementary particles, or relative strength of several of the physical forces were not extremely close to what they are now, stars and the complex molecules that lead to life could never have developed.

Time and Space. (Credit: Brisbane Falling via Flickr)

The odds of randomly hitting upon a life-permitting universe seem infinitesimal. When discussing how a relatively small change in the magnitude of dark energy would preclude life, physicist and author Paul Davies wrote, “The cliché that ‘life is balanced on a knife-edge’ is a staggering understatement in this case: no knife in the universe could have an edge that fine.” The problem is to explain why the universe’s constants and laws are so precisely fine tuned as to allow for complexity and life. Even if, as another physicist and author Victor Stenger argued, this  ”fine tuning problem” can largely be explained by  established physics, the deep mystery of why our universe has specific parameters and laws that allow complexity and life to emerge in the first place still remains.

Okay, so we have the significant problem of explaining organized complexity and the appearance of design.

We have been here before.

Before Darwin, the prevailing view was that each species was specially created and did not change over time. We now know that species are not timeless or designed, and that cumulative change is possible naturalistically through generations by Darwinian evolution.

Referring to biological complexity, evolutionary biologist and author Richard Dawkins wrote, “The theory of evolution by cumulative natural selection is the only theory we know of that is, in principle, capable of explaining the existence of organized complexity.” Some have called evolution by natural selection the single best idea anyone ever had.

If that is true, why stop at biology? “Nothing in biology makes sense except in the light of evolution,” evolutionary biologist Theodosius Dobzhansky wrote. Is it possible that, faced with a similar daunting challenge to explain complexity and the appearance of design, nothing in cosmology will make sense except in the light of evolution either? Obviously, evidence is essential in science, and we’ll get to that. If thought of broadly, in biology it’s evolution all the way down. Maybe in cosmology, it’s evolution all the way up as well.

Lee Smolin. (Credit: Lumidek via Wikimedia Commons)

The most full proposal for the mechanism of cosmological natural selection comes from physicist Lee Smolin.

Here is the mind-blowing hypothesis that he first outlined in 1992 in his book The Life of the Cosmos. Throughout the universe, stars that collapse into black holes squeeze down to an unimaginably extreme density. Under those extreme conditions, as a result of quantum phenomenon, the black hole explodes in a big bang and expands into its own new baby universe, separate from the original. The point where time ends inside a black hole is where time begins in the big bang of a new universe. Smolin proposes that the extreme conditions inside a collapsed black hole result in small random variations of the fundamental physical forces and parameters in the baby universe. So each of the new baby universes has slightly different physical forces and parameters from its parent. This introduces variation.

Because of their inherited characteristics, universes with star-friendly parameters will produce more stars and reproduce at a greater rate than those universes with star-unfriendly parameters. So the parameters we see today are the way they are because, after accumulating bit by bit through generations of universes, the inherited parameters are good at producing stars and reproducing.

The Life of the Cosmos book cover. (Credit: Wikimedia Commons)

So that would be a logical explanation to the deep “fine tuning problem” – the parameters in our universe are the way they are because of non-random naturalistic cumulative inherited change through reproductive success over time. If correct, we live in a lineage of offspring universes – which visually could be depicted like the expanding branches on the biological tree of life.

The existence of stars is a prerequisite for the formation of life. This is because carbon and most of the other complex molecules that allow for life are created in stars. So the same conditions that promote the most new universes would be the same conditions that allow for life.

Smolin takes great pains to claim his hypothesis is scientific because it is falsifiable. He proposes several ways that his conjecture can be disproved. But the larger point for us is not whether Smolin’s specific proposed mechanism for cosmological natural selection is true. The point here is to emphasize the power, beauty and logic of cosmological natural selection as a scientific hypothesis to explain complexity and the appearance of design, even if the precise mechanism of cosmic heredity and variation has not been determined.

The claim of cosmological natural selection is not that it has a 1 to 1 exact analogy to biological natural selection. For evolution by natural selection to manifest its extraordinary power, the fundamental feature of the process that must be preserved is differential reproductive success of heritable variations and cumulative change. The technical details of what constitutes environments, populations, etc., and whether or not phenomena like species, mating opportunities and direct competition come into play, depend on the local specifics. So, the claim is that the hypothesis of cosmological natural selection maintains the essence of a universalizable natural selection process, with all its explanatory majesty.

The real criticism of cosmological natural selection as a scientific hypothesis is its lack of direct evidence at this point. There is no direct evidence that the universe reproduces. Without that, no natural selection, even before issues of variation and selection come into play. True enough. But keep in mind that from a direct evidence perspective, cosmological natural selection is no worse off at this point than proposed scientific alternatives. There is no direct evidence that universes are created by quantum fluctuations in a quantum vacuum, that we live in a multiverse, that there is a theory of everything, or that string theory, cyclic universes or- brane cosmology even exist.

And the major proposed alternatives in cosmology do not directly or logically explain the “fine tuning” problem for the existence of complexity and life. Instead, they suggest things like some sort of inevitability, design, unimaginably incalculable luck or an infinite number of multiple universes where every possible universe exists. That last one is enough to make Occam cut his throat with his razor.

If, ultimately, some version of cosmological natural selection is proved true, as I think it will be, it will go well beyond giving the best logical explanation for why our universe’s parameters allow for complexity and life. There would, in addition, be deep and profound implications related to human meaning and existence.

In a world of branching universes conducive to life, ultimate cosmic doom may be avoided, keeping alive the possibility of eternity – not for us as individuals, or for Homo sapiens, but for the existence of life at large in the cosmos. If cosmological natural selection proves true, life almost certainly is not unique in the history of the cosmos. As was shown with biological natural selection, we are of nature and part of nature. The universe could be further understood as a self-coherent and self-creating whole, without the need for anything outside itself to give it law, meaning or complexity.

If cosmological natural selection proves true, we would not live in a determined world, but in a changing cosmos with an open future. This can be interpreted as optimistic and hopeful. But while processes such as natural selection may allow for the development of life—and there is something spectacularly marvelous about that—there is no evidence that the universe as a whole has consciously planned anything, has life as its conscious goal or consciously cares about our fate. The human tension between the heroic and the humble, this blending of the significant and the insignificant, can be a source for comedy, tragedy or inspiration.

Ultimately, it will come down to evidence. Science rules by evidence. Our minds expand, while the God of the gaps gasps.

If evidence proves any one of the cosmological alternatives—or an entirely new idea altogether—we will embrace reality, no matter where it leads, and be struck with awe at our ability to discover the grandest of cosmological truths and our place in the universe.

Lawrence Rifkin About the Author: Lawrence Rifkin is a physician and a writer. Links to his writings on science, meaning, humanism, and medicine are at lawrencerifkin.wordpress.com. Follow on Twitter @LSRifkin.

The views expressed are those of the author and are not necessarily those of Scientific American.






Comments 15 Comments

Add Comment
  1. 1. M Tucker 5:02 pm 06/10/2014

    “In a world of branching universes conducive to life, ultimate cosmic doom may be avoided, keeping alive the possibility of eternity – not for us as individuals, or for Homo sapiens, but for the existence of life at large in the cosmos.”

    I think you are saying the cosmos is this eternal, infinite, series of collapsing stars giving birth to new universes. And it sounds like you are saying that since it is infinitely eternal it needs no beginning and there will be no end. I do have an open mind but I can’t help but think you are just playing games with the concept of infinity.

    So from a single collapsing star it is possible to create all the mass and energy contained in an entire universe? One single star…gives rise to an entire universe…fantastic! My simple, none physicists mind struggles to understand how so much can come from so little.

    So what determines how much mass and energy a universe can contain? I mean all the mass…even dark matter. What determines how much energy a universe can contain? I mean dark energy too. Oh, wait, you physicists call it dark because you really don’t know what it is. If you have trouble with what seems to be fundamental characteristics of a universe, why is it so many of you seem so confident in coming up with these theories? Even if your theory is falsifiable. Your theory needs to adequately explain the whole universe including dark matter and dark energy; not just the fine tuning question.

    Link to this
  2. 2. jtdwyer 5:16 pm 06/10/2014

    While their may be (especially simple) lifeforms elsewhere – and at other times in the universe, there is no compelling evidence that life is even possible in any but an exceedingly select group of very specialized environments. In this view, this is not generally a “life permitting universe”. Given the total number of discrete environments in the universe, it should not require much ‘fine tuning’ to produce a few that can support even complex life – although not necessarily all at the ‘same time’.

    Link to this
  3. 3. micha 5:19 pm 06/10/2014

    As M Tucker wrote: “I think you are saying the cosmos is this eternal, infinite, series of collapsing stars giving birth to new universes. And it sounds like you are saying that since it is infinitely eternal it needs no beginning and there will be no end. I do have an open mind but I can’t help but think you are just playing games with the concept of infinity.”

    I would say that Smolin is simply advocating a theology — an infinity beyond the reach of science being used to explain effects that are within its reach. The only difference is that rather than positing a “Will of God” to answer the grand question of “Why”, one is using this impersonal Infinity to eliminate the question of purpose.

    M Tucker’s question is this new nihilistic religion’s version of “If God created the universe, who created God?”

    Link to this
  4. 4. Damir Ibrisimovic 5:25 pm 06/10/2014

    What about changing fine structure “constant” (∝) in “our universe”? Do we really need then “other universes” at all? And, how we could empirically prove existence of “other universes”?
    Imaginative leaps of faith are nice – as long we land into our universe; without, per definition, empirically unverifiable components. Our universe is still full of surprises to keep us busy for millennia to come. And, I doubt that adding more universes into the mix is helpful – apart from grabbing teenagers’ imagination and some ill-invested funds.

    Enjoy the day,
    Damir Ibrisimovic

    Link to this
  5. 5. theo52 5:28 pm 06/10/2014

    The statement “We now know that species are not timeless or designed,” has a problem. How do you KNOW, I think the word “know” should be changed to “believe”.
    Darwinian/Macro evolution has never been observed and the evidence supporting it is circumstancial and open to intepretation – it is poor science to mix a fact with a belief.

    The whole presumption that Darwinian/Macro (also known as molecules to man) evolution is a scientific fact is really poor science. Our science students are badly deceived by this teaching.

    Consider just a small number of fundamental scientific problems with Darwinian/Macro evolution which expose its fallacy
    1) Where did the information come from to build the DNA molecule?
    – it contains over 4 Gigabits of programming data; we have never observed natural forces creating programming data
    - a building is proof of a builder, a program is proof of a programmer, a design is proof of a designer
    2) How did genders “evolve” from asexual organisms?
    - Consider some of the challenges, have a look at this video http://youtu.be/Ab1VWQEnnwM

    3) How do you explain symbiotic relationships while holding to gradual “evolution”?
    - e.g.. The bees need the flowers, the flowers need the bees – they both MUST exist together, how could this occur slowly or gradually
    - What came first the Chicken or the egg?
    4) Where are all the myriad of transition fossils that Darwin predicted?
    - They were missing then and they are missing now.
    - How can the Cambrian explosion of millions of fully formed organism appearing abruptly be explained by Evolution?
    5) Which “evolved” first, the vagina or the penis?
    - how did one “evolve” from the other?

    Dr John Sanford (Geneticist and inventor of the GeneGun) said :
    “The bottom line is that the primary axiom [of Darwinian/Macro evolution] is categorically false,
    you can’t create information with misspellings, not even if you use natural selection.”

    Link to this
  6. 6. chris_weiss 6:43 pm 06/10/2014

    Theo ->

    As you have been told many times, John Sanford’s claim that the genome is degrading has been shown to be false. It is unfortunate that you keep copying and pasting this over and over.

    DNA is not like a program. It is a template. Comparing it to a program is a bad analogy. Information theory does not apply. Also, given the variety and relative inefficiency of the genome seen across animals, it is obvious that our genome was not “designed” or “programmed.”

    In comparison to gender, did you know that some animals have their gender determined by embryological temperature and not DNA? If a temperature variation can determine gender, the development of gender is far less mysterious.

    The Cambrian explosion is a misnomer. This time period covers several million years. It was not “overnight,” unless you have a different definition of “overnight.” Similarly, during the Cambrian period we have the development of hard bodied animals and cordates, which contributed greatly to variation. Since soft bodied animals don’t generally leave fossils, we can’t even be sure how diverse life was before the Cambrian period.

    You copy and paste the same misinformation over and over. Can you at least develop some original material? Your current round of criticism have long since been addressed.

    Link to this
  7. 7. Trafalgar 6:55 pm 06/10/2014

    > While their may be (especially simple) lifeforms elsewhere – and at other times in the universe, there is no compelling evidence that life is even possible in any but an exceedingly select group of very specialized environments.

    Do you know how many stars there are in the universe? So many that there are going to be quite a few planets like ours. We’re just not very good at detecting them across the vast distances of interstellar space yet.

    > In this view, this is not generally a “life permitting universe”.
    Cogito ergo sum. Ipso facto, quod erat demonstrandum.
    Your argument is an argument from ignorance.

    > it contains over 4 Gigabits of programming data; we have never observed natural forces creating programming data
    You’re joking, right? We’ve observed natural forces altering DNA all the time. Cells evolved to mutate, to swap DNA, etc, and that is what we see. Human-created computer programs for the most part are programmed to do none of those things because that makes them impossible to debug. That said, people have made programs that use genetic algorithms, which evolve, which compete against other programs to determine which is the most fit, etc.

    > a building is proof of a builder, a program is proof of a programmer, a design is proof of a designer
    I’m sure you’re real upset about whoever planted those dandelions all over your lawn.

    On the topic of the article: If the conditions of the ‘original universe’ were such that black holes could not form, then this could never happen, so considering the vast number of possible values for universal variables in the cosmos, whose alteration could easily result in a lack of black holes, we’re right back where we started: for this theory to work the original universe has to have been designed or lucky enough to permit black holes and for those black holes to create new universes.

    I think it’s far more likely that the many-worlds hypothesis is correct, and there are simply universes for all possible combinations of all possible values of all variables, and all possible physical laws, etc, such that any possible universe that can hold life will exist… Along with all the universes where life cannot exist, the universes where stars may not be able to exist, or the only thing that exists are black holes, universes where the Flying Spaghetti Monster exists and is locked in an endless holy war with Cthulhu, etc….

    Link to this
  8. 8. jtdwyer 9:55 pm 06/10/2014

    Trafalgar,
    “Do you know how many stars there are in the universe? So many that there are going to be quite a few planets like ours.”
    Is this really your compelling evidence? How many stars does it take to produce one planet that someday might support complex life? Keep in mind that even the Earth could only support simple life forms for many billions of years – the majority of its existence!
    There are other issues – see http://www.astrobio.net/topic/deep-space/cosmic-evolution/deadly-stellar-winds-could-put-a-stop-to-life/ http://www.nature.com/news/wind-may-deflate-search-for-habitable-planets-1.15335 and http://news.sciencemag.org/space/2014/04/false-signs-life-alien-worlds

    Link to this
  9. 9. Bee 12:17 am 06/11/2014

    “If, ultimately, some version of cosmological natural selection is proved true…”

    You can’t prove scientific hypotheses true. Besides, for all I know CNS has been proved wrong since the book was written. It predicts an upper limit for the mass of neutron stars, see http://arxiv.org/abs/hep-th/0612185 section 3.2 and that doesn’t seem to hold, see eg http://www.nature.com/news/2010/101027/full/news.2010.565.html

    Link to this
  10. 10. GSChandy 7:35 am 06/11/2014

    theo52: God dunnit!

    How do I know?

    The Holey Bubble tells me so!

    GSC

    Link to this
  11. 11. jtdwyer 3:26 pm 06/11/2014

    Bee – well done!

    Link to this
  12. 12. andyboerger 11:02 pm 06/11/2014

    This is an astonishingly silly piece of writing. So ‘natural selection’ is why our universe is the way it is (the writer says he’s pretty sure we’ll discover that one day)?
    First of all, let’s define terms. In the broadest sense, I guess you could say that oceans are ‘naturally selected’. That is, as the natural low areas where water collects, their size, and ultimately the fact that they exist at all, is ‘selected for’ (by, duh, gravity). But NOBODY talks about NS that way. It is almost exclusively used to describe the way that biology operates, and necessitates considering reproduction and the passing on of traits to offspring. Think about that for a minute. Natural selection, as it is currently discussed and studied, exists only on the crust of this one planet, as far as we know. Probably 99.9999% of all the matter on this planet has no connection whatsoever to natural selection, unless you want to reduce it to a meaningless truism (which I don’t think the author does). Expand that to talk about our solar system, and then you are approaching something like 99.9999999999999999999999999999999999999999999999999% of all matter not being ‘naturally selected’. And yet this preposterous article wishes to posit Natural Selection as operating at the metacosmic level, giving birth to universes???? Pass me whatever he is smoking.

    Link to this
  13. 13. profchuck 6:28 pm 06/12/2014

    I see two (at least) ways to view this issue. The anthropic principal argument (if it were otherwise we would not be here to ask the question) and the concept of spontaneous order. The anthropic argument is a dead end but spontaneous order is interesting. An over simplified view is that complex systems seem to evolve from simpler ones. Quarks to sub atomic particles, sub atomic particles to atoms, atoms to molecules, and molecules to even more complex systems including living organisms. It may be that this reversal of entropy is a natural phenomenon like gravitation or electromagnetism. There are many possible combinations of quarks but only the stable ones survive. The same is true of atoms, molecules and so on. Adam Smith described the action of what he called “the unseen hand” in economics. It may be that the phenomenon is much more wide spread than that. It may even be part of a fundamental principal.

    Link to this
  14. 14. BobWalton 1:49 pm 06/14/2014

    I hypothesize that there is a compartment in the human psyche that attends to ‘Where do we come from; where are we going?’ Perhaps it evolved originally to define where an individual fits in in the family/tribe/society. In it, among other things, we find religion and cosmology, perhaps located fairly far apart in the file. The potential for irrationality in the output from this compartment is quite high. I personally like the idea of an infinite universe, and was saddened when Hoyle’s Continuous Creation was supplanted by the Big Bang. I found the idea of a universe that ultimately fades to nothing quite depressing. I therefore have to admit that Smolin’s hypothesis of a never-ending series of evolving universes is very interesting, but concede that that may be because it puts me back in my (not necessarily rational) comfort zone.

    Having said all that, I think back to what J B H Haldane said a long time ago: ‘Not only is the universe queerer than we understand; it’s queerer than we CAN understand.’

    Link to this
  15. 15. GregRobert 5:13 pm 06/15/2014

    I’ve always believed this. I find it excruciatingly hard to describe but like people say, “evolution is SUCH a good idea we should look for it everywhere. It’s the only thing we know of that can extract order from choas.

    I also believe in what I call the anti-entropic principle which answers the single question of why the increase of entropy is so amazingly slow. Photons emitted by the sun are absorbed by plants, shaved of a little energy and re-released as infrared, which are a notch higher in entropy. Couldn’t nature find a faster more efficient methods. It’s as if the universe DOESN’T want to grow up.

    We see this everywhere. Why?

    Link to this

Add a Comment
You must sign in or register as a ScientificAmerican.com member to submit a comment.

More from Scientific American

Scientific American Dinosaurs

Get Total Access to our Digital Anthology

1,200 Articles

Order Now - Just $39! >

X

Email this Article

X