IACP12

The Cosmological Replication Cycle, the Extraterrestrial Paradigm and the Final Anthropic Principle

B. A. Balazs

Department of Astronomy, L. Eotvos University

Budapest, Hungary

Abstract: The aim of those men who created the upheaval in the seventeenth century, which we now call the “Scientific Revolution” was not the conquest of Nature, but the understanding of Nature. “Yet their cosmic quest destroyed the medieval vision of an immutable social order in a walled-in universe together with its fixed hierarchy of moral values, and transformed … the society, culture, habits and general outlook as thoroughly as if a new species had arisen on this planet.”*

The aim of SETI is not to conquest but to understand either. We cannot even guarantee success in a trivial, superficial sense. But at its deeper levels SETI certainly stimulates and influences our thoughts and transforms our society. In the present paper we are going to touch four of the most thought-provoking related items:

· SETI is a logical, essential extension of the current Origins Program;

· Life is not a blind chance but an integral part of the universe, strongly favored by the physical laws and constants of inanimate nature.

· The emergence of increasingly intelligent life is a robust phenomenon, plays an important role in the cosmological replication cycle, and its manifestations should make up an important part of our world picture.

· SETI is a basic source of the understanding of our position in the universe. In the deepest sense the search for extraterrestrial intelligence is a search for our origin, fate and real identity.

This contribution offers a compact survey of the items described above.

*Quotation from A. Koestler (The Sleepwalker, Preface).

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As far as the first item (NASA’s Origins Program) is concerned, it is known that basically as a reaction against exaggerated subservience to the Copernican principle, Carter (Carter, 1974) in the early seventies introduced the so called anthropic principle, which in its weak form declares that we must be prepared to take into account the fact that _iiiii

our location in the universe is necessarily privileged to the extent of being compatible with our existence as observers. Now, if it turns out that ETI exists and the case of mankind is not exceptional, the final step of the Copernican revolution is done: the place of the Earth is not central even in the sense of harboring intelligent life.

It was disillusioning for us to learn, that the Earth goes around the Sun, that there are other suns, other galaxies, maybe other universes. It was humbling when we discovered that we are descended from inferior animals. But now we can cherish some definite hope to have highly developed extraterrestrial “kinsfolk” somewhere outdoors.

Simply our body provides the best indication. Evolution and natural selection is supposed to provide for adaptive demands and even so curiously had equipped homo sapiens with an organ – our brain – which (utilizing only two or three per cent of its capacity) he was unable to put to proper use up to the present day. Since evolutionary genetics is incapable to explain this oddity, there is a chance that at least a part of our genetic code is not of local origin and just the success of SETI – giving us a comparison with other beings – can finally throw light on the origin of this apparent paradox

.

Entering upon the second item, we have to note, that according to the majority of the evolutionary theorists the probability of the emergence of human-like intelligence through the natural process of biological evolution is vanishingly small (Gould, 1990) and therefore our appearance is generally considered as an extremely improbable event. Some renowned contrarians (e.g. Wilson, 1998; Wright, 2000) take an opposing position, arguing on the basis of the omnipresent trend of convergent evolution and other indications, that the emergence of human-level intelligence was absolutely probable, almost ineluctable. After all Gustav Arrhenius studying tiny apatite grains in the Isua formations in Greenland has found carbon 12 to13 ratios consistent with the grains originating from living matter. The Isua rocks are 3.85 billion years old. This suggests, that life appeared on our planet as soon as environmental conditions allowed (Arrhenius at al., 1996). Life thus arose within the first billion year of Earth’s formation from the protoplanetary disc. By what means was this possible?

Although we can rightly conclude, that living beings are too complicated – statistically too improbable – to have come into existence simply by chance, this conclusion is valid only for a single, sole act of chance. But the phylogenesis consists of a long series of minute chance steps – genetic mutations –, each one small enough to be a real product of its predecessor. Only a tiny minority of them turns out to be slight improvements regarding survival and reproduction, but by the process of natural selection the beneficial changes will gradually spread through the species and grow to be the norm. Our body – far too complex to have come into being in a single act of chance – is actually a result of a very long selective chain of tiny steps, the timescale of which is almost 2 million times longer than the whole history of Christianity. It is very hard indeed for the human mind to comprehend such an immense tract of time.

This reasoning is surely not restricted to the Earth. Based on the principle of mediocrity we can safely conclude, that the phylogenesis goes on everywhere in the universe, where the conditions are suitable for it. One basic phenomenon associated with the behavior of complex adaptive systems – and therefore with any kind of phylogenesis – is emergence, which has superbly been described by John Holland (Holland, 1998): “We are everywhere confronted with emergence in complex adaptive systems – ant colonies, networks of neurons, the immune system, the Internet and the global economy to name a few – where the behavior of the whole is much more complex than the behavior of the parts.” The following characteristics of the phenomenon of emergence are notable in the context of development of life and natural or artificial intelligence:

· The possibilities for emergence improve “when the elements of the system include some capacity, however elementary, for adaptation or learning.”

· The “component mechanisms (in an emergent system) interact without central control.”

· “Persistent patterns at one level of observation can become building blocks at still more complex levels”, leading to a “hierarchical organization (configurations of generators become generators at a higher level of organization).”

The last feature is particularly important, because it entails, that the number of hierarchical levels belonging to a particular emergent phenomenon can be infinitely large, and that satisfactorily advanced hierarchies of rudimentary components as simple as primordial subatomic particles are capable of eventually producing such sophisticated phenomena as human civilization and artificial intelligence.

We will now turn our attention to the third item. It appears, that the physical laws and constants of our universe are very finely tuned to support life, and quite a number of competent authorities take fine-tuning to be an explanandum that doesn’t speaks for itself. Our current best physical theories and the Big Bang scenario in cosmology have a number (twenty or so) free parameters, and man could never come into being in a universe in which one or the another of the basic constants or parameters is altered by merely a few percent one way or the other. We have selected five of them as follows:

· Number of spatial dimensions. Two space dimensions are purely geometrically not enough to allow for the development of sophisticated beings like us. In four space dimensions (e.g.) the orbits of planets would be unstable: the least disturbance would result in the earth spiraling away from or away into the sun.

· The initial rate of expansion. If the rate of expansion one second after the Big Bang had been less merely by one part in 10¹⁰, the universe would have collapsed after a few million years, and if it had been greater by the sane amount, the universe would have been practically empty after the same period. Therefore it wouldn’t have lasted long enough for life to develop.

· Neutrinos, the weak interaction. Carbon and some heavier elements are absolutely necessary for our life. These elements are manufactured in stars and spread across the Galaxy when a minority of them explodes as supernovae. Computer calculations had shown that a burst of neutrinos (originated in the core region) is indispensable in helping the shock wave of the blast to blow the star apart. If the weak interaction, the force that determines how neutrinos interact with baryons, were a little too weak, then even the dense shock wave would be transparent for neutrinos; if, on the other hand, the interaction were a little too strong, the neutrinos would never get out of the core.

· Electron/proton charge equality. Any charge imbalance would force every object in the universe – our bodies, rocks, planets, stars etc. – to explode immediately. The balance must be extremely precise. We would fly apart if the two charges differed by as little as one part in 100 billion!

· Neutron/proton mass differential. In our world the unstable neutron outweighs the proton, which is a stable particle. The mass difference is only a tenth of a percent (roughly the mass of an electron). In the opposite case the neutrons would be stable and all protons would decay into neutrons. Therefore, if the difference were reversed, hydrogen, water and most of the stars would not exist. Solid bodies would collapse rapidly into neutron objects or black holes, and we would certainly not be here to discuss the case.

It seems reasonable to doubt that there is a proper physical theory on the basis of which our universe is not fine-tuned. Renowned physicists – like John Wheeler – explicitly deride all efforts to derive the values of physical constants and the laws of nature from time-invariant principles (Wheeler, 1994): “…the laws of physics cannot have existed from everlasting to everlasting. They must have come into being at the one gate in time, and fade away at the other.”

At the present time two possible explanations are contemplated commonly: the design hypothesis (which involves superior beings, principles or mechanisms external to our physical world and accountable for selecting its properties) and the ensemble hypothesis. In the present paper we intend to deal with the second one, the meaningfulness of which is not so much in question. It states that our universe (a large, casually fairly but not entirely separated space-time region) is only a minor part of the totality of physical entity (multiverse). With the words of Nick Bostrom (Bostrom, 2000): “This totality itself needs not be fine-tuned; if it is sufficiently big and variegated, so that it was likely to contain as a proper part the sort of fine-tuned universe we observe, than an observational selection effect can be invoked to explain why we see a fine-tuned universe.”

The member universes of the multiverse can simply coexist or be genetically connected. The two most established proposals, which can account for the spreading of the ‘family tree’ of the universes are the concept of eternal chaotic inflation¹ (Linde, 1998) and the process of cosmological replication and natural selection (Harrison, 1995; Smolin, 1997; Gardner, 2000), but only the second one offers a reasonable explanation for the problem of fine-tuning.

According to Smolin the anthropic qualities² of the cosmos are simply conse- quences of a process of cosmological replication and natural selection, the utility function³ of which is black hole maximization. (Smolin imagines, that during the collapse of a black hole a rebound occurs that spawns one or more universes. He suggests that although the laws and basic constants of nature are mutable, the crucial parameters in the new ‘baby universes’ only slightly differ from those of the ‘mother universe’.) A universe where black holes (potential offspring) are abundant must have a large number of stars (to turn into black holes) and a suitable amount of carbon (to help condense stars from interstellar matter), consequently must have anthropic qualities.

Smolin’s new cosmological paradigm, a classification of the universe as a self-organizing replicator that contests for reproductive success within a multiverse of rival replicators, is really fascinating, but has some obvious flaws (e.g. Vaas, 200). The two most conspicuous of them are the following ones:

· The Darwinian analogy of cosmological natural selection is somewhat misleading, because the members of the multiverse have no significant interaction with an environment, and the process of their reproduction is not constrained by external factors.

· Any Darwinian theory “depends on the prior existence of the strong phenomenon of heredity. There have to be self-replicating entities (in a population of such entities) that spawn daughter entities more like themselves than the general po-pulation” (Dawkins, 1997). With this in view perhaps the most serious shortcoming of

Smolin’s hypothesis is the lack of memory. (There is no genetic transmission of traits without a certain kind of recollection.) Indeed, if a black hole evapo- rates its mass away via Hawk- ing radiation, which is a pure blackbody emission, it carries none of the information about the matter that originally collapsed. Then why should parameters change slightly and not arbitrarily during the replication?

As it was pointed out by John von Neumann in his classic lecture “On the General and Logical Theory of Automata” (first published by Jeffress, 1951) any self-reproducing object must contain four indispensable components:

· a blueprint, providing the plan for construction of offspring;

· a factory, to carry out the construction;

· a controller, to ensure that the factory follows the plan; and

· a duplicating machine, to transmit a copy of the blueprint to the offspring.

The first two components could imaginably be supplied respectively by the set of physical laws and constants of our universe and by our world itself (Pagels, 1984, 1986), but for the time being it is far beyond anything that we can comprehend, that any mechanism of the inanimate nature might be capable to imprint the fundamental laws and parameters of our world in a ‘baby universe’.

Some six years ago R. Harrison (Harrison, 1995) has proposed a thought-provoking solution, which might be able to supply the last two von Neumann components: the controller and the duplicator. He suggests, that our universe was made by super-intelligent forms of life living in another universe⁴. Since their universe must be compatible with their existence, it must be basically similar to our own. Let us assume, that — as a consequence of the primordial chaotic inflation — there were an initial ensemble of universes, in which the fundamental constants have random variations, containing at least one universe, where intelligent life develops. In accordance with the phenomenon of emergence mentioned above, life is capable of attaining the capacity to engage in cosmological engineering and to improve the ability of the universe to reproduce. With the words of Freeman Dyson (Dyson, 1988): “there are good scientific reasons for taking seriously the possibility, that life and intelligence can succeed in molding the universe … to their own purposes…It appears to me, that the tendency of mind to infiltrate and control matter is a law of nature.”

For us the final goal is still very very distant, but already perceptible. As it was shown by E. Farhi and A. H. Guth (Farhi & Guth, 1987), it may be really possible to create a universe under controlled laboratory conditions, by forming a black hole of about 10 kg mass from particles at energy ~ 10¹⁵ GeV. The physical constants of the offspring universe would then probably be pretty similar to the values in the parent universe.

Turning our attention to the fourth item, there is no doubt about it that the on-going SETI projects may turn out as a crucial test of the robustness of the emergence of human-like (and superhuman) intelligence and as a basic source of the understanding of our position in the cosmos.

Ever since Aristarchus became conscious of the vastness of the universe, either Ptolemy thought that we are at its center or Copernicus cleared we are not, people have widely accepted the possibility that other worlds house other intelligent beings (Dick, 1982; Crowe, 1986). The conviction in the ‘plurality of worlds’ is generally based on three beliefs: on the so-called “principle of plentitude” which declares that what can exist must exist everywhere where the conditions are suitable for it; on the “principle of mediocrity” which takes for granted that our existence is noting out of the ordinary, and on the “infinity of the cosmos” which – on the by- condition that the laws of nature are everywhere the same – assures that any event with non-zero probability must occur unlimited times in the universe.

It is obvious that in support of the first two principles SETI is of basic importance. “There is no stronger army in all the world than an idea whose time has come” wrote Victor Hugo in 1870, and the time for the scientific foundation of the ‘plurality of worlds’ and for the intensive search for extraterrestrials has certainly come. During the last years quite a number of prominent opponents of SETI have changed their minds. The most peculiar case is the one of Frank Tipler who as lately as in 1980 still took the view that “extraterrestrial intelligent beings do not exist” (Tipler, 1980) and in 1994 published an astonishing book on his W-Point-Theory (Tipler, 1994), the most important presupposition of which is the anthropic principle in its sharpest form as final anthropic principle claiming that “life and intelligent life are not only necessary within our universe, but can also no more disappear after their first emergence. Rather they are destined to pervade and dominate the entire universe.” It is impossible not to see, that the final anthropic principle combined with the principle of mediocrity is a firm argument in support of SETI.

Owing to Kurt Gödel’s incompleteness theorem (Gödel, 1931), the frequently raised question on the pure existence of ETI’s is not a suitable one; only the frequency of occurrence in a well defined region (e.g. in a stellar system) of the universe can be treated by scientific methods. In the discussion of the number (N_c) of technological civilizations in our Galaxy two general forms of the well-known Drake equation have been widely used (see f. i. Kreifeldt, 1971). For our purpose Cameron’s formulation is the more proper one, according to which

N_c = N_s f_s L_c/L_p , (1)

where N_s is the number of potentially suitable parent stars, f_s is a compound selectivity factor, L_c is the length of the communicative phase of a society and L_p is the part of the lifetime of a planet during which highly developed species can exist on it.

Only an estimate of L_c is beyond the reach of conventional astronomical

methods (see f. i. Balázs, 2001). It is not accidental, that by far the most controversial issue of the entire equation is that of L_c. The proposed values markedly depend on our global situation of the moment. Accordingly a rather pessimistic figure of 10 years was accepted at the Green Bank conference in 1961, at a time, when the cold war and the threat of a fatal nuclear exchange just got to their culminating point. Albeit the value of L_c can now rightly be increased from 10 to at least 50, the only hopeful possibility to forecast our far future with any reasonable probability is provided uniquely by the success of SETI (giving a direct estimate of N_c)_.

To sum it up, the advent of a new cosmological era and the oncoming victory of the extraterrestrial paradigm (our long-term future will be determined by extraterrestrial ventures and contacts) will strongly stimulate and influence our thoughts on ourselves and on the world then will presumably result in a radical change of our view on the role of life in the cosmos.

One has to adopt a strictly super-Copernican standpoint (Wheeler’s phrasing in his famous book “At home in the Universe”, Wheeler, 1994): We got very far away from any anthropocentric vision of the universe, yet at the dawn of the third millennium we begin to realize, that life is not a blind chance but an essential component of the cosmos. Life and intelligence play an important role in the cosmological replication cycle, and they are predestined to pervade and dominate a whole ‘family’ of universes. Dyson rightly concluded in his remarkable book “Infinite in all directions” (Dyson, 1988), that science provides a solid foundation for a philosophy of hope: “I have found a universe growing without limit in richness and complexity, a universe of life surviving forever and making itself known to its neighbors across unimaginable gulfs of space and time.”

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Notes

¹ Most versions of inflation predict the existence of other universes (actually an infinity of random universes).

² In the context of the multiverse hypotheses the anthropic principle acts to select those universes that are “interesting” for us, i. e. capable of supporting self-aware consciousness. In this picture, the distinction between the weak and strong forms of the anthropic principle is meaningless.

³ A utility function transforms an outcome into a numerical value and measures the worth of an outcome.

⁴ The super-intelligent beings assumed by Harrison are part and “natural product” of the parent universe, so his proposal cannot be considered as a variation of the design hypothesis. The assertion, that our universe is the first in the reproduction cycle of fine-tuned universes would violate the Copernican principle (our case would be exceptional).

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(This paper was supported in part by the OTKA grant T034998.)

In: Proceedings of the 12th Congress of the International Association ”Cosmos & Philosophy”,

28 Sept.- 1 Oct. 2001, Aegina, Greece (in press)