The Size of the Universe as a Cultural and Theological Question
The overwhelming disproportion of the size of the universe as compared to our human size has always been a matter of concern and surprise in the reflections about our relation with God and the Universe. Though God is thought to be beyond time and space, this disproportion is usually felt as amazing and paradoxical enough as to cast doubts on the possibility of a loving God caring for us, and as cutting us from any possible cosmic relevance. The feelings and ideas on this disproportion are especially relevant in current reflections on time and space, and for exploring our connection with cosmic evolution, and the relation between different levels of reality in a non-reductionist perspective.
Of course, this sensation has changed accordingly to the several cosmological models: it was not so intense in the Ptolemaic model, with Earth at the center and a relatively small universe, as in the Copernican Universe, with Earth no longer at the center and very distant stars, or as in the Big Bang cosmology, where galaxies are mere points in a much wider and dynamical universe. Furthermore, it depends on our view of the origin of life and of human beings: the idea of a direct divine origin in a relatively recent past inspires rather different thoughts and feelings than a chemical origin of the first cells followed by a long and random biological evolution. An excellent overview of the role of cosmic ideas in western thought is provided by Brague (1999). Some parallelisms between open questions in current physical cosmology and a few cultural highlights of religious cosmology have been pointed by Jou (2008).
It is interesting to examine the cultural impact of this topic as expressed by literary works of different epochs. We provide here a brief survey of it, including contemporary poetry. This reference to poetry allows us to deal not only with science but also with the topic of how science stimulates new poetry, and how poetry may convey philosophical and theological considerations to a wide public, as related to the beauty and mystery of the universe. We feel indeed that science may be a powerful stimulus to poetry and to arts, and that it plays a relevant role in imagining or representing some aspects of our relation with sacred aspects of reality.
The main aim of this lecture will be to consider the disproportion between visible universe and human life from the perspective of the current cosmological model (Russell et al 1991, Rees 1997, 2002), in spatial, temporal, and informational perspectives, in the framework of an evolutionary Creation Schmitz-Moorman 1997, Edwards 2004, Polkinghorne 2007). Our conclusion is that this quantitative disproportion does not mean a qualitative disproportion, but that the relative â€œimportanceâ€ of human life in the cosmos seems higher than the one that could be intuitively suspected from a bold consideration of the huge quantitative disproportion. In other terms: life has a deep cosmic dimension, independently of its abundance. To be able to contain at least a single cell, the observable universe must have a size of the order of four or five billion light years, and to contain at least a single intelligent species, it must have some ten billion light years. Amazing as this may sound at first, this is due to the historical dimension of life, incorporating the formation of atoms in stars and the complex prebiotic chemical processes and Darwinian evolution.
Some poetical expressions of our cosmic smallness
First of all, we refer to the literary expression of the mentioned feelings of smallness as compared to the cosmic size. We think that the exploration of the literary and artistic expression of philosophical and theological questions is far more than an anecdotic and marginal issue, as art and literature have a strong cultural impact on a wide public, not directly involved in intellectual speculation. On the other side, it provides a historical view on past ideas, and makes us more aware of cultural evolution and of permanent questions. Finally, it may yield fresh inspiration for the communication of new ideas to contemporary public, thus leading to a confluence of science, arts and religion as three main ways of exploration of the actual reality.
However, our aim is not exclusively literary and historical, but mainly scientific and contemporary. This forces us to concentrate here on only five poetical works. This is enough to convey the diversity and intensity of the mentioned uneasiness in some sufficiently different historical times. In particular, we will refer to the Psalms, to Dante Alighieriâ€™s La Divina Commedia (1321), to John Miltonâ€™s The paradise lost (1667), to Blaise Pascalâ€™s PensÃˆes (1670), and to Eureka. An essay on the Material and Spiritual Universe (1848), a cosmic essay by Edgar Allan Poe.
In the Psalm 8, the fact that God may be mindful of mankind is seen as a surprise, after considering the immensity of His Creation:
When I consider your heavens, the work of your fingers,
the moon and the stars,which you have set in place,
what is man that you are mindful of him,
the son of man that you care for him?
The cosmic grandiosity underlines, in this view, the tremendous gift that is the loving attention of God on humanity. In the context of a strong belief, this grandiosity is not seen as casting doubts on the existence nor providence of God, but as a stimulus to celebrate His fatherly attention to our smallness.
The Paradise of Danteâ€™s Divina Commedia is structured according to the Ptolemaic cosmology. In it, Dante, guided by Beatrice, ascends the several planetary spheres up and beyond that of the fixed stars, where he will find the direct presence of God. In Canto XX, Dante looks back from Saturn, the highest planet in the Ptolemaic model, to the other planets and the Earth, and he is shocked by their minute size:
Col viso ritornai per tutte quante
le sette sphere, e vidi questo globo
tal, ch’io sorrisi del suo vil sembiante;
e quel consiglio per migliore approbo
che l’ha per meno; e chi ad altro pensa
chiamar si puote veramente probo.
In English translation:
I straight obey’d; and with mine eye return’d
Through all the seven spheres, and saw this globe
So pitiful of semblance, that perforce
It moved my smiles: and him in truth I hold
For wisest, who esteems it least: whose thoughts
Elsewhere are fix’d, him worthiest call and best.
Here, the Earth is seen as a tiny and miserable grain of dusk, contaminated by the human weaknesses, fights, and ambitions, thus adding to the spatial smallness the sense of moral misery. God is not so much a loving Father, as in the Psalm 8, but a kind of Cosmic Emperor. Incidentally, the vision of the Earth as a very small planet has much current interest in the contemporary views, where the ease and efficiency of communications, human overpopulation, the forthcoming shortage of fossil fuels, and the problems related to air and water pollution and their climatic consequences makes us to see our planet as finite and vulnerable.
Miltonâ€™s Paradise Lost, written three centuries and half after the Divina Commedia, is another capital literary reference. Here, the struggle between Evil and God through the Creation is represented in a grandiose cosmic scenario, no longer dominated by the serene and transparent order of the Ptolemaic model used in the Divina Commedia, but by the uncertainty between this old model and the new, but still debated, Copernican model. Milton, by the way, visited Galileo at his home during his travel to Italy, and admired very much his scientific work. In Book VIII of Paradise lost, Adam asks to Raphael
The thirst I had of knowledge, and vouchsafed
This friendly condescension to relate
Things, else by me unsearchable; now heard
With wonder, but delight, and, as is due,
With glory attributed to the high
Creator! Something yet of doubt remains,
Which only thy solution can resolve.
When I behold this goodly frame, this world,
Of Heaven and Earth consisting; and compute
Their magnitudes; this Earth, a spot, a grain,
An atom, with the firmament compared
And all her numbered stars, that seem to roll
Spaces incomprehensible, (for such
Their distance argues, and their swift return
Diurnal,) merely to officiate light
Round this opacous Earth, this punctual spot,
One day and night; in all her vast survey
Useless besides; reasoning I oft admire,
How Nature wise and frugal could commit
Such disproportions, with superfluous hand
So many nobler bodies to create,
Greater so manifold, to this one use,
For aught appears, and on their orbs impose
Such restless revolution day by day
Repeated; while the sedentary Earth,
That better might with far less compass move,
Served by more noble than herself, attains
Her end without least motion, and receives,
As tribute, such a sumless journey brought
Of incorporeal speed, her warmth and light;
In these verses, the disproportions of Nature cast a shadow of doubt on the existence of God or, at least, on the human possibility of understanding the seemingly superfluous excess of reality. They provide an explicit and transparent expression of the sensation of amazement from the fact why, if God was really interested in human beings, made also so many other distant stars â€“or some many other biological species, one could add-, which do not seem to bear any relation with human existence nor human welfare.
In the same century as Milton, the French mathematician and philosopher Blaise Pascal (1623-1662) wrote a famous sentence of his PensÃˆes, another much respected literary masterpiece,
Le silence eternel de ces espaces infinis mâ€™effraie.
The eternal silence of these infinite spaces fills me with dread.
In this sentence, he reflects how the immensity of the universe does not properly constitute by itself a meaningful â€œcosmosâ€, put it may lack of any sign approaching to the experience of God or the meaning of life. Though not a poet from the formal sense, many of his PensÃˆes, have a strong and moving poetical and intellectual force. He also writes on the subject of our cosmic smallness another famous sentence:
Qu’est l’homme en regard de la nature ? Rien par rapport â€¡ l’infini, tout par rapport â€¡ rien, une moyenne dans un tout,
or, in English translation of the whole paragraph ,
He who sees himself thus will be frightened by himself, and, perceiving himself sustained… between these two abysses of infinity and nothing, will tremble… and will be more disposed to contemplate these marvels in silence than to explore them with presumption. For in the end, what is man in nature? A nothing in respect to the infinite, everything in respect to the nothing, a halfway between nothing and all. Infinitely far from comprehending the extremes, both the end and the beginning or principle of things are invincibly hidden in an impenetrable secret; he is equally incapable of seeing the nothing whence he has been drawn, and the infinite in which he is engulfed.
In these sentences, the frightening sensation of infinity and nothingness invite to a silent contemplation of our human being in connection to the secrets of God and the Universe. In more recent times, a related kind of feelings may be found, for instance, in Monodâ€™s book Chance and necessity (1971): “Man at last knows he is alone in the unfeeling immensity of the universe, out of which he has emerged only by chance”. Monod writes from a very different perspective than Pascal, not that of an enquiring believer, but as a convinced atheist, but he also expresses this sense of cosmic silence, solitude, and disproportion.
Our last reference to a poetical work will be to Eureka. An essay on the Material and Spiritual Universe, a cosmic essay by the American poet and writer Edgar Allan Poe, deeply interested in astronomy and in cosmic speculations. The Olberâ€™s paradox (1823) about the inconsistency of an infinite and eternal universe, which should lead to a brilliant night sky instead to a dark sky was a source of reflection and inspiration for Poe. He expresses his thoughts in a long text in prose. In relation to the subject we are dealing with here, namely, the disproportion of the cosmic space, Poe states that:
Our fancies thus occupied with the cosmical distances, let us take the opportunity of referring to the difficulty which we have so often experienced, while pursuing the beaten path of astronomical reflection, in accounting for the immeasurable voids alluded to -in comprehending why chasms so totally unoccupied and therefore apparently so needless, have been made to intervene between star and star -between cluster and cluster- in understanding, to be brief, a sufficient reason for the Titanic scale, in respect of mere Space, on which the Universe is seen to be constructed. A rational cause for the phaenomenon, I maintain that Astronomy has palpably failed to assign: -but the considerations through which, in this Essay, we have proceeded step by step, enable us clearly and immediately to perceive that Space and Duration are one. That the Universe might endure throughout an aera at all commensurate with the grandeur of its component material portions and with the high majesty of its spiritual purposes, it was necessary that the original atomic diffusion be made to so inconceivable an extent as to be only not infinite. It was required, in a word, that the stars should be gathered into visibility from invisible nebulosity -proceed from nebulosity to consolidation- and so grow grey in giving birth and death to unspeakably numerous and complex variations of vitalic development it was required that the stars should do all this -should have time thoroughly to accomplish all these Divine purposes- during the period in which all things were effecting their return into Unity with a velocity accumulating in the inverse proportion of the squares of the distances at which lay the inevitable End.
Poe mentions the immeasurable and needless distances between star and star, and, curiously enough, he refers to the relation of these distances to the time necessary to give birth to life, a connection we will deal with in deeper detail in our contemporary context. Thus, Poe tries to understand the size of the universe in connection to life. In his essay, Poe was led to some intuitive anticipation of a dynamical universe, without any scientific basis at that time. His essay provides an interesting example of how poets do not only use accepted cosmic images, as Dante, or participate in the struggle between two different cosmological models, as Milton, but are attracted by the paradoxes and problematic aspects of such models and go beyond them, without any scientific guide but with astonishing intuitions, which will find a wide acceptation in the future, but not because of poetic power of persuasion but because of strictly scientific observations and theories.
After this brief survey of human amazement in front of the immensity of the Universe in these four pieces of poetry, we turn our attention to this topic from the point of view of current cosmology.
Spatial perspective: cosmic immensity as a necessary requirement for our existence
To consider our relation with cosmos from the spatial perspective, we take into account three facts of our current scientific view of cosmos and life: the formation of the atomic nuclei of our body by fusion reactions in stars, the evolution of life, and the cosmic expansion. According to the standard Big-Bang model, when the Universe was three minutes old, it was composed only of hydrogen and helium 4, and a tiny amount of lithium, deuterium and helium 3, in some well-known proportions. Indeed, for times shorter than three minutes, the universe was so hot that fusion reactions of hydrogen into helium were taking place in the whole space. This is the moment where the contents of the Universe are the simplest ones: the unstable elementary particles had disappeared, antimatter had annihilated with a corresponding amount of matter, and only hydrogen and helium nuclei, electrons, neutrinos and photons were present; and the heavier elements beyond helium had still not appeared in the cosmos. This stage of cosmic simplicity lasted some three hundred thousand years, during which the universe expanded and cooled keeping always a spatially homogeneous state. Had the universe expanded at a faster rate that it did, the expansion would had been too fast for the formation of galaxies to occur, and the contents of the Universe would have remained forever restricted to these two light elements, plus a tiny amount of helium 3 and lithium.
The other elements originated by fusion reactions in stars. Formation of galaxies and of stars with planetary systems is a hot topic of research, because of the interest on dark matter, which supposedly increased the rate of galaxy formation, and on extrasolar planets. The formation of atomic nuclei requires the formation, evolution and explosion of a first generation of big stars which, after forming the nuclei beyond hydrogen and helium, up to iron, explode as supernovae and expand their contents in the galaxy.
The duration of stars depends on their mass; bigger stars, being hotter than smaller ones, have a shorter duration, because they consume their nuclear fuel at a higher rate than smaller stars. The earliest stars were very big, because they formed in a rather dense universe, and lasted only a few hundred years, but the total amount of produced heavy elements was not still high enough. Another population of slightly smaller stars was necessary to produce a sufficient amount of heavy elements for solid planets to be formed in a latter generation of stars. The strict restrictions on the values of the physical constants for the formation of carbon nuclei and other nuclei are well known, and are at the basis of the anthropic considerations, and we will not deal with them. The whole process described in these paragraphs takes some four or five billion years.
After this injection of heavy atoms in the galactic dust, a third generation of stars must be formed, some of them endowed with planetary systems containing planets constituted by atoms required for the future formation of molecules with biological relevance. On the Earth, the formation of the first bacteria took some six hundred million years of frenzy chemical activity. Thus, it may well be said that the minimum size of the observable Universe to be able to contain, let us say, a single bacterium is of the order of four or five billion light years. This is really astonishing, as the size of a bacterium is overwhelmingly smaller than the size of the visible universe. However, the material and the structure of the bacterium require a long time to exist. Time and space are linked in a subtle way, that goes beyond mere reductionism. Life is formed not only of matter, but also of time. Without the historical perspective on matter, the relations between life and cosmos cannot be well understood.
The evolution of life up to the formation of an intelligent species in our planet has taken some four billion years. It could be that, in some other hypothetical planet, the time necessary to reach an intelligent species could have been slightly shorter, or slightly longer. Since evolution has many random aspects, this kind of history cannot be known. In fact, the history of life on several planets in the universe could be a kind of â€œsum over historiesâ€ â€“paralleling the famous expression by Feynman in relation with the evolution of a quantum system-. But, during these long processes, the universe has been expanding at a high speed; in particular, the frontier of the observable universe has expanded with the speed of light.
Thus, after consideration of all these facts we conclude that intelligent species could not exist in a small universe, namely, a universe smaller than some ten billion light-years of size, in the same way as a single bacterium cannot exist in a universe smaller than some five billion years light.
This consideration is one of the most amazing consequences of the current cosmological model. The immense number of galaxies that â€œseem to roll spaces incomprehensible, merely to officiate lightâ€ (to mention Miltonâ€™s words) are not useless and superfluous after all, but a necessary condition for the existence of life. Thus, â€œhow Nature wise and frugal could commit such disproportionsâ€ is now more understandable than in previous times. They are a consequence of universe expanding in a fast way and its initially homogeneous contents breaking and organizing in an immense set of galaxies, as a consequence of the hydrodynamic instability of such self-gravitating gas.
Temporal perspective: informational time versus linear cosmic time
We have already emphasized the deep connection between temporal and spatial features for the universe to be able to contain some life. The temporal perspective may yet be examined from an additional point of view. Indeed, from a temporal perspective, one standard argument to dismiss our cosmic relevance is to say that, would be the history of the universe written in fourteen big volumes, one for each billion years, human beings would not appear until the last few lines of the last page of the last volume. However, we may examine this matter from the perspective of an informational interpretation of time, instead of the linear vision of time of mechanical clocks, and the conclusion is rather different (Sallantin 1989).
Indeed, the description of the first three minutes of the universe requires an enormous amount of information, as it implies several symmetry breakings of the fundamental physical laws, leading from a hypothetical unified force to the observed four different physical interactions, a number of phase transitions from a quark-gluon plasma to a hadron gas, or from a universe almost symmetric in matter and antimatter to the one formed by only matter, and the processes of primordial nucleosynthesis. In contrast, the period until the recombination process, where hydrogen and helium nuclei and free electrons become a neutral gas, with the consequent decoupling between matter and radiation, lasts three hundred thousand years, and it is described by only two simple expressions, relating the cosmic scale factor and the cosmic temperature to the elapsed time (simple relations in which the scale factor increases as the square root of time and temperature decreases as he reciprocal of the square root of time).
Thus, the information required to describe the evolution of the universe is not linear with time, but there are periods whose description requires much information â€“the first three minutes, galaxy formation, the origin of life, the biological evolution, the origin of intelligenceâ€“ and other periods which do not imply almost any information. In particular, the information required to describe the origin and evolution of life and of intelligence would be far bigger than the one required for describing the formation and evolution of a star or of a lifeless planet. A simple way to have an estimation of the informational proportion of life as related to cosmos could be to compare the number of pages devoted to physics, astrophysics, and cosmology with those devoted to molecular and cellular biology, evolution, and neurobiology on the shelves of the library of a standard sciences faculty. According to this rough estimation, the information related to the essential processes of life is considerably bigger than the one related with the essential physical processes, and therefore, in this perspective, the relative presence of life would be considerably relevant instead of negligible.
In thermodynamic terms, the relative â€œweightâ€ of time may be related to enytropy production, because of the connections between entropy and information; in the theory of nonlinear and chaotic systems, Kolmogorov entropy is used instead of the more macroscopic entropy production (Nicolis and Prigogine 1989, Russell et al 1993). This may give, if necessary, a specific quantitative meaning to the mentioned informational relativity. The informational perspective of time presented here is close to an Aristotelian view of time: indeed, to establish that the state of a system has changed it is necessary that we have information on the states to be compared; on the other side, it is close to our psychological perception of time, where there are very intense moments, full of significance, and long routine periods where nothing new happens. In the informational perspective, the disproportion between human and cosmic information is not so disparate as in a linear routine interpretation of time.
Complexity perspective: brain and universe
A third aspect worth of examination is the large-scale complexity of the universe, as described in physical cosmology, and of the human brain. Here we take as basic entities galaxies, in one case, and neurons, on the other one. Of course, both galaxies and neurons are in themselves complex entities, but we will not delve into this inner complexity, but into with the collective, global complexity of visible universe and of human brain.
In the visible universe there are some one hundred billion stars, and our brain comprises a similar number of neurons. However, all the galaxies interact through the gravitational interaction, whereas the neurons interact through many different kinds of synapses â€“excitatory, inhibitory, with different kinds of neurotransmitters and different intensities, which may be modified in time, according to complex learning processes or to plasticity processesâ€“. Two very close neurons may be as unrelated as two very distant galaxies if they are not interconnected through a synapse. In this way, the point of view of complexity, as related to interactions between physical objects, also contributes to illustrate the relativity of the relevance of physical distances. Thus, from the perspective of brain complexity, human beings are not so extremely disparate from the cosmos.
Considering the informational aspects of the Universe, and not only matter and energy, may open new perspectives, subtler than the previous ones (Lloyd 2007). Information by itself does not necessarily carry a meaning, which stands beyond signs and characters. A necessary condition for meaning is some inhomogeneity and structure in the elementary signs carrying information. This may have some analogy with the formation of stars from a previous homogeneous hydrogen gas. The gravitational instability of the gas and the further contraction of big gaseous masses to eventually form stars introduce new kinds of atomic matter, which open in the long run the possibility of life. The contraction of previously homogeneous and meaningful information to new hierarchical orders may open the possibility of internal meaning. Probably, human brain is the privileged space for a higher meaning.
Concerning size, the central topic of our discussion, it may be remembered that information is not directly related to physical size. One example is the increasing miniaturization of computer memories, leading to the accumulation of an enormous amount of information, previously contained in more than a hundred books, in minute spaces of pen drives or hard disks. Another example could be to consider idioms with very different number of users: a bigger number of users is not related to a subtler expressivity, nor to more complex or powerful syntactical rules. Again, size is not necessarily a fruitful measure of being.
The usual view of the believer in front of the immensity of the Universe is surprise and awe. He accepts that Godâ€™s immensity is compatible with an immensity of cosmic space. However, seeing this immensity as a necessary requirement for our existence, rather than a superfluous excess, yields an intellectual satisfaction which harmoniously complements the ontological sense of reverence and of dependence. In this way, the current scientific view has something new to say in the long stream of reflections about our cosmic disproportion, that we have summarized in a few but outstanding literary works.
In some of my poems, I have tried to express this new vision of infinity as a necessary condition for our existence, as a fruitful space rather than an absurd void immensity without any connection to our existence. In this poem I compare the usual frightening view of such immensity with the new vision, which intensifies our spiritual sensation of forming a part of a whole in which very distant galaxies have something to do with the conditions for our being in this world. This is only an instance of how science may arouse a dialogue with philosophical topics, and this dialogue may give rise not only to a rational discussion but also to a truly emotional resonance, which may be useful to awake the attention of a public which is not used to the subtleties of science and philosophy, but which may be attracted to them when they feel it is touching their own deep curiosities.
The poem says, in the original Catalan version (Jou, 2007):
Em negaves, infinit,
mâ€™anulÂ·laves sota tË™muls de llum indiferent,
mâ€™aclaparaves amb vertÃŒgens de buit,
mâ€™esglaiaves amb silencis dâ€™astres morts,
creixies sense fi en tots els telescopis,
i sabÃŒem que seguies mÃˆs enllâ€¡ de tota mirada,
de tota fantasia del desig i tota gosadia de la ment.
PerÃš ara sentim una altra mË™sica:
si no fossis tan gran no podrÃŒem ser,
el foc de les estrelles no ens hauria sabut coure.
El nostre preu Ãˆs lâ€™infinit,
maternal, paternal, fredament condescendent,
clavat a lâ€™â€¡nima en forma de nostâ€¡lgia,
un pes massa gran per resistir-lo,
perÃš no de buidor
sinÃ› de no saber com dir una carn tan fosca
amb claror que estigui a lâ€™altura de tants astres.
Germans de lâ€™infinit perÃš clavats a la mort,
sense saber com acceptar la finitud del temps
ni com omplir dâ€™infinitud la vida,
sota tË™muls de llum indiferent,
sota vertÃŒgens de buit,
sota silencis dâ€™astres morts,
perÃš sabent que sÃ›n un preu que no sabem com valdre.
In English translation by Elisenda Vila (2007), the poem is:
You denied me, infinity,
you annihilated me under mounds of indifferent light,
you bewildered me with vertiginous emptiness,
you frightened me with the silence of dead stars,
you grew endlessly in all the telescopes,
and we knew you continued beyond everyoneâ€™s gaze,
beyond any longing fantasy of desire and any mental dare.
But now we hear another tune:
if you werenâ€™t as big as you are we couldnâ€™t be,
the fire of the stars wouldnâ€™t have known how to cook us.
Our price is infinity,
maternal, paternal, coldly condescending,
nailed to the soul in the form of nostalgia,
a weight too heavy to resist,
mind you, not of emptiness
but of not knowing how to name our dark body
with enough light to match the many stars.
Brothers of the infinite but nailed to death,
without knowing how accept the finite nature of time
nor how to fill life with infinitude,
under mounds of indifferent light,
under the silence of dead stars,
but knowing that they are a price that we are unable to value.
In fact, following the literary expression of the sensations of forming a part of a deeper and higher whole would be a very long topic, ranging from the classical Greeks to our modern times, and would imply not only cosmology, but also our views on atoms, on energy, on biology, on ecology, on Earth, and it could be expressed, in different ways, in mystical writings.
The relation of our small size to the grandiosity of cosmos could be expressed in terms not only of space, or of time, or of complexity, but also on probabilistic terms. The less is a part with respect to a whole, the less probable seems it, a priori â€“provided equal spaces have equal probability, as in the phase space of equilibrium systems in statistical mechanics-. We will not deal longer with this point, but we only want to outline that, in the views of evolution, it is known that the most improbable events may trigger the most innovative and far reaching changes, as emphasized, for instance, by Schmitz-Moormann (1997). Here, we have noted that the existence of life requires an enormous number of stars, i.e., that the improbability of life in relation to cosmos has some logical grounds, related to the probability distribution of the size of stars, of the size and distance of planets with respect to their stars, on the galactic environment and the relative positions of stars in their respective galaxies, etc. These features have been discussed in detail in the context of the SETI project (Search for Extraterrestrial Intelligence), in the so called Drakeâ€™s formula, which analyzes the probability of the several factors necessary for the formation and evolution of life up to intelligent beings. In our analysis, we have not gone to such a detailed view, related to the possible number of intelligent civilizations, but we have focused our attention on the temporal scale necessary for the existence of intelligent beings.
Another topic that one could analyse in the context of the cosmic immensity is whether the whole Universe is truly infinite, or only immensely bigger than our observable universe, or smaller than our visible universe â€“indeed, in some models of closed universes, the actual universe could be smaller than the observed universe, as the number of observed galaxies would be smaller than the actual number of galaxies, because we would received several different images of every galaxy, their respective light arriving to us along different pathsâ€“. This is still a topic under discussion. Although a flat universe is usually assumed to be infinite, it has been mentioned the possibility that the universe is closed but with a polyhedral form. In this way, instead of having everywhere a non-vanishing curvature, it would be flat in big regions but in some small regions it would have a strong curvature. Such a polyhedral model is not disproved by the the WMAP observations on the cosmic background radiation. It is expected that new observations of Plankâ€™s satellite may yield more precision on the spatial correlations of the cosmic background radiation and may decide whether this polyhedral possibility of a finite universe is acceptable or not.
Still another question, deeply related to the anthropic principles, is whether a very high number of very big universes â€“rather than a single big universeâ€“ must exist for the existence of a life-containing universe to be possible. In this setting it is imagined that the values of the physical constants would be randomly distributed in the several universes, and our universe is a one that per chance has the right values of these constants for heavy elements formation (in particular, for carbon formation), necessary for life. Since these topics have been already widely discussed, we have focused our interest on the size of the observable universe, which is the one we may admire in the astonishing images of the current telescopes, as the Hubble telescope, and which has had a longer and deeper impact in literature. This topic is accessible to observation and closer to emotions that the more abstract and subtle physical setting of the values of the physical constants, on which the usual analyses of the anthropic principles are based.
In summary, the current view of the expanding universe, nuclei formation, planetary systems formation, the evolution of life, and the relevance of complexity, modifies our intuitions about the apparently overwhelming disproportion between an immense universe and our existence. We have emphasized that the minimum size for a universe to contain a bacterium is of the order of four billion light years, and to contain intelligent life its size must be of the order of ten billion light years. In the same way, and by the same arguments, it could be said that the minimum size of the universe to contain a single carbon atom must be of the order of a some millions of light years. Thus, the size is not meaningful as a criterion for comparison of the different levels of reality. The time necessary for the required processes for the formation of atoms and the organization of molecules and the constitution of living structures is extremely relevant.
On the other side, the role of information and complexity in the Cosmos is another topic worth of attention. The complexity of the brain is comparable or higher than the large-scale complexity of the universe, and spatial and temporal immensity of the universe is a necessary â€“but not sufficientâ€“ condition for our existence â€“or the existence of other intelligent speciesâ€“, and it is not necessarily a hint of our ontological insignificance.
I acknowledge useful discussions with Prof. Dr. Manuel G. Doncel and other members of our MGNI Group STIC (Seminari de Teologia i CiÃ‹ncies) of Barcelona, in Sophia Iberia, which are working in different topics of our project â€œHuman evolutionâ€. I am grateful to the invitation of the Metanexus Institute to participate in this Metanexus Conference as the representative of our Metanexus group.
Brague R, La sagesse du monde. Histoire de lâ€™experience humaine de lâ€™univers, Fayard, Paris, 1999 (English translation The Wisdom of the World. The Human Experience of the Universe in Western Thought, Chicago, The University of Chicago Press, 2003)
Edwards D., Breath of life. A theology of the Creator spirit, Orbis Books, 2004
Jou D, The scriptures of the Universe (poetry), Servei de Publicacions, Universitat AutÃšnoma de Barcelona, bellaterra, 2007
Jou D, Reescribiendo el GÃˆnesis. De la gloria de Dios al sabotaje del universo, Destino, Barcelona, 2008
Lloyd S., Programming the Universe. A quantum computer scientists takes on the Cosmos, Vintage Books, Random House, New York, 2007
Nicolis G and Prigogine I, Exploring complexity, Freeman, New York, 1989
Polkinghorne, J, Science and Creation (SPCK/New Science Library, 1989; Templeton Foundation Press, 2006)
Rees M, Before the beginning: our universe and others, Addison-Wesley, London, 1997
Rees M, Our cosmic habitat, Phoenix, London, 2002
Russell R J, N. Murphy and J. C. Isham, eds, Quantum cosmology and the laws of Nature, Scientific perspectives on Divine Action, Vatican Observatory Publications & CTNS, 1991.
Russell R J, N. Murphy and A.R. Peacocke, eds, Chaos and complexity. Scientific perspectives on Divine Action, Vatican Observatory Publications & CTNS, 1993.
Sallantin X, Le monde nâ€™est pas malade, il enfante, Oeils, ParÃŒs, 1989
Schmitz-Moormann K, Theology of Creation in an evolutionary world, Pilgrim Press, London, 1997