Talk:Fecund universes

Merge
Why on earth are there two separate pages on this, each referring to the other? Obvious case for merger, surely! PaddyLeahy 21:50, 15 April 2007 (UTC)
 * Actually, it may be that we wish to leave cosmological natural selection for Lee Smolin and fecund universe for more than Smolin? On second thought, merging sounds fine. -- kanzure 12:40, 16 April 2007 (UTC)
 * I absolutely agree. It is absurd - undoubtedly this was caused by two people, each creating a page without knowledge of other page. Merger is quite nessescary.
 * While I vote to merge, be careful. The cosmological natural selection page is more fleshed out, but "cosmological natural selection" itself is something of a misnomer (as there is no selection, only variation) I would suggest a merge to Fecund universes as the single, definitive article for this topic Tarcieri 05:59, 12 June 2007 (UTC)
 * Tarcieri, I agree that is a misnomer, and an odd one at that. Lee Smolin was supposedly the one to start using the phrase "cosmological natural selection", and here I thought he was good friends with Kauffman enough to know that natural selection is more than organisms/systems killing themselves (apoptosis but spelled correctly). -- kanzure 15:17, 13 June 2007 (UTC)

Lack of any interest in WP:V
I just did some checking into the history of the article, the bulk of it was written in a 3-hour period in October 2005 by an anonymous editor under the (since merged) title Cosmological natural selection. Nobody since has shown the slightest interest in providing citations. I am therefore reducing it down to a lead/stub & transfering the bulk of the article here. If you want any of this stuff back on main space then SOURCE IT! 17:12, 25 January 2008 (UTC)


 * So tag the article, don't delete the entire thing. —Preceding unsigned comment added by 12.184.170.5 (talk) 15:43, 4 April 2008 (UTC)


 * It was tagged for being completely unreferenced for more than two months before I turned it into a redirect (a month ago). HrafnTalkStalk 16:01, 4 April 2008 (UTC)

Background
The theory surmises that a collapsing black hole causes the emergence of a new universe on the "other side", whose fundamental constant parameters (speed of light, Planck length and so forth) may differ slightly from those of the universe where the black hole collapsed. Each universe therefore gives rise to as many new universes as it has black holes. Thus the theory contains the evolutionary ideas of "reproduction" and "mutation" of universes, but has no direct analogue of natural selection. However, given any universe that can produce black holes that successfully spawn new universes, it is possible that some number of those universes will reach heat death of the universe with unsuccessful parameters. So, in a sense, in cosmological natural selection universes could "die off" before successfully reproducing, just as any Human can die without having children.

This universe should not be the first
If this theory is correct, the odds strongly favor this universe being not the first to ever exist, but a descendant of many that have previously existed. And, since a universe with conditions favoring production of many 'child' universes, i.e. favoring black hole production, would have many more 'children' than one that did not, it is reasonable to expect a late universe to have 'evolved' towards conditions favoring black holes. Additionally, it is interesting to note that black holes do not necessarily have to be the original structures allowing for the near-exact reproduction of the universe, and in fact it may prove to be more likely that black holes are an emergent phenomena from the (possibly) long-line through the hierarchy of universes to our current universe instance.

Falsifiable or unfalsifiable
Some critics have claimed that this theory is not falsifiable, and therefore unscientific. By definition, existence of "other universes" cannot be verified by scientific tools working within the time-space and physics laws of our universe. Smolin's counter-argument is that an observation of very many black holes in the known universe would be evidence for this view, while if black holes are rare or unusual, it would be quite strong evidence against; and since the hypothesized evolutionary process would be expected to find local maxima in fecundity, were a small change in cosmological parameters found to give rise to a universe favoring black hole production more than ours, this too would provide evidence against the theory.

Meduso-anthropic principle
Louis Crane has proposed a Meduso-anthropic principle, which suggests that universes could be fine-tuned for life by intelligent beings themselves manufacturing new universes. He argues that the destiny of highly evolved intelligence (perhaps our distant progeny) is to infuse the entire universe with life (similar to what Ray Kurzweil proposed in The Singularity is Near), eventually to accomplish the ultimate feat of cosmic reproduction by spawning one or more “baby universes,” which will themselves be endowed with life generating properties.

Smolin's fecund universes theory was the subject of a science fiction short story by David Brin, entitled "What Continues, What Fails ...", and was a common theme in Stephen Baxter's novel Manifold: Time and the rest of the manifold trilogy.

The problem of undetermined parameters
The standard model of elementary particle physics aims to unify the forces of nature so that they all possess the properties of a gauge field. This gauge field can be broken down naturally when combined with matter fields. In this way, we see that all the forces of nature are in fact the same force and so it only takes a small list of parameters to define all the forces in the universe (other than gravity). The matter fields have split these forces into those, which we witness in our universe. However, while all forces (other than gravity) have their origin in the gauge field, there is no known origin for the matter fields that exist in our universe. The masses of the particles in our universe seem to be arbitrary in nature, not determined by any known mechanism.

If these values are in fact arbitrary, why then do they just so happen to possess just the right values to produce a universe so complex? A one percent change in the mass of the neutron or proton, or a doubling of the electron's incredibly small mass, would yield a universe with no chemistry and no stars. Hydrogen gas would be the only element in the universe. See Fine-tuned Universe.

A multitude of universes
Virtually all hypotheses which attempt to explain this complexity involve the postulate that there is a very large or infinite number of universes called the Multiverse. Each one has its own set of mass fields. When applied to this assumption, the anthropic principle concludes that our universe is a rare exception within this large set of universes and that by chance it possesses exactly those characteristics necessary for our kind of life to exist. Since the number of universes is so large, it is expected that some of them will contain complexity. The problem with this explanation is that it is not falsifiable and is therefore unscientific in nature. That is, we know of no mechanism by which we can detect the existence of other universes.

Black holes may generate new universes
Modern scientific theory, however, does provide a mechanism by which universes can be formed. The original theory of general relativity predicted that when a black hole was formed it collapsed into a singularity. That is, space and time would become so curved here that everything would collapse into a point. General relativity also predicted that our universe sprang from a singularity during the big bang. But we now know that general relativity breaks down below the Planck length. It is here that quantum mechanics begins to play a part. For this reason, physicists have suspected for a long time that a singularity would violate the uncertainty principle, and hence cannot exist. Recently, this conjecture has been investigated mathematically. This is still speculative, but according to one theory of quantum gravity a singularity is not formed. Instead, space and time do not collapse to a point but rather into a (four-dimensional) tube which opens into an entirely new region of space and time. The singularity "bounces" back out into a big bang. This means it is entirely possible that our own universe was produced when a black hole was formed in another universe.

Evolving universes
Lee Smolin's hypothesis of cosmological natural selection makes the assumption that each universe developed in such a way possesses slightly modified versions of the mass fields of its "parent" universe. This concept is of course borrowed from Darwin, and is analogous to mutation of genes in modern evolutionary theory. There is some conjectural support for this in both string theory and quantum gravity. The change in the mass fields would be due to the intense energies and small scales reached within a black hole. By a simple extrapolation it is easy to see that universes which generate more "offspring" will ultimately become more numerous. A universe with no stars and consisting entirely of hydrogen gas can produce only one offspring because it can produce no black holes. All it can do is collapse back in on itself in a "big crunch", a reverse big bang, to generate a singularity.

Some universes produce more offspring
Given enough universes, some would by chance possess the matter fields necessary to generate stars and thus black holes. Since these would produce far more offspring, they would become far more numerous than universes without stars. (There is no known mechanism that "kills off" universes and so there is no actual parallel to "natural selection" in the theory of cosmological natural selection. It is for this reason that it is now technically referred to as fecund universes.)

Our universe may optimize black hole production
What Lee Smolin proposes is that a universe which produces more black holes than any other would in fact possess the laws of physics our universe does. He argues that cosmological natural selection is superior to the anthropic principle because it is falsifiable. That is, if we discover anything in our universe suggesting our universe is not ideal for producing black holes, the theory is disproven. The falsifiability in this case depends strongly on a principle of mediocrity, however. Even if universes amenable to black hole production spawn far more universes than those that are not, there is still an anthropic landscape of possibilities. If there is an alignment of the parameters necessary for intelligent life and for black hole formation, then the fact of our existence has little effect on the prior probability part of a Bayesian calculation, but we can never neglect the possibility that we may live in a universe far from the peak of the distribution of parameters. At best, then, the principle of mediocrity provides probabilistic falsifiability. The scientific validity of such reasoning is the subject of much philosophical debate.

In addition, a thorough calculation of what exact values of the mass fields would generate a universe with the largest possible number of black holes may lead to predictions of so far unobserved elementary particles or other attributes of our universe. Unfortunately, this is not possible today.

[End of transfered material HrafnTalkStalk 17:12, 25 January 2008 (UTC) ]