Not a matter of timing : Lemaître on creation

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1 Not a matter of timing : Lemaître on creation
Interdisciplinary workshop in honour of Monseigneur Georges Lemaître December 1-2, 2016, Academia Belgica, Rome

2 B. Disraëli Tancred: or, the New Crusade (1847)
Can Theories of Everything deal with « Nothing »? “everything is explained by geology and astronomy; and in that way. It shows exactly how a star is formed […] You know, all is development. The principle is perpetually going on. First, there was nothing, then there was something; then I forget the next, I think there were shells, then fishes; then we came, let me see, did we come next? Never mind that; we came at last”. Talk of creation out of nothing implies tlak of “nothing” as such. Is is witthin the scope of natural sciences ?, or even o any rational discourse at all ? In one of his novels, Benjamin Disraëli describes the enthusiasm of a Lady (Constance Rawleigh) for a book entitled The Revolutions of Chaos: (Tancred: or, The New Crusade (1847), Bradenham edition, vol. X, Peter Davies (London: W.C., 1927), Book II, chap. 9, pp ). The Lady is fascinated by the explanawardsry power of natural sciences ; and no doubt, this power deserves admiration. This is the fascinating power of theories of everything. But she seems to imply that the principle of development, explains everything, including the coming-into-being of the universe from scratch. This is a serious issue as to whether theories in physics are likely to account for the very existence of whatever, and in particular to account for the transition, if any, from no-thing at all to something. What is the trouble with this alledged transition from no being to some being ? B. Disraëli Tancred: or, the New Crusade (1847)

3 From « no things » to « things »
“No one is going to show how a state of affairs in which there were no things of any sort developed into a state of affairs in which there were things” (Peter Van Inwagen, Metaphysics) « No things » = a physical state of affairs ?… or rather = no state of affairs at all (no dimensions, no variables, no vacuum, no field…)

4 Troubles with « First there was nothing »
Time → events → things Observational/Theoterical means to get a glimpse of « Nothing » ? Extrapolation of observational data to « nothing at all » ? No, according to Lemaître. Absolute nothingness beyond the boundary or edge of space-time ? No, even along Borde-Guth-Vilenkin views. Inductive arguments (Mackie, Swinburne) to a finite duration a parte ante ? There may be problems with the premiss “First there was nothing” First, if time is a relational property, that supervenes on events, which occur to things : no things, no events, no time. Once there was nothing turns out to be paradoxical (this line of reasoning is to be found in Lemaître) Second, have we observational/Theoterical means to get a glimpse of « Nothing » ? Large Nothingness Collider, Nihiloscope ? In which appropriate terms of a physical theory can we describe pure nothingness (quite different, from vacuum or from processes of creation/annihilation of particles, which still involve physical parameters) As we shall see, Lemaître provides us with arguments to the claim that, within the framework of natural sciences, we cannot extrapolate our data to « nothing at all » Absolute nothingness is not to be located beyond the boundary or edge of space-time. For « absolute nothingness »is not to be located at all. If it has a location, it is something that has a location. The fact that we have no model to predict or explain what could take place before or beyond an hypothetical wall, does not allow us to infer that there is nothing at all; Having nothing to say does never allow to say there is nothing. Sure there are philosophical discussions as to whether a finite duration of the universe a parte ante is more plausible than an everlasting universe ( See Richard Swinburne, ‘The Beginning of the Universe and of Time’, Canadian Journal of Philosophy, 26, (1996)). But this is metaphysics, not physics, it still does not allow us to claim that physics provides us with a state of affairs where there is nothing Let us now turn to consider the contribution of Lemaître to this issue.

5 Lemaître 1927 : «Un Univers homogène de masse constante et de rayon croissant, rendant compte  de la vitesse radiale des nébuleuses extra-galactiques », Ann. Soc. Scient. de Bruxelles, 47A Let us begin with Lemaître’s paper of 1927 (translated 1931) : « A homogeneous Universe of constant mass and growing radius accounting for the radial velocity of extragalactic nebulae » (Monthly Notices of the Royal Astronomical Society, 91, ) « 6. Conclusion. We have found a solution such that: 1. The mass of the universe is a constant… 2. The radius of the universe increases without limits from an asymptotic value R0 for t = −∞… 3. The recession velocities of extragalactic nebulæ are a cosmical effect of the expansion of the universe. »

6 Einstein’s ironical congratulation
This is the most beautiful and satisfactory explanation of creation I have ever listened to !

7 From suspicion to denial Einstein: « Your calculations are correct, but your Physics is atrocious. No ! This is too much suggesting… a creation ! » «J’ai rencontré Einstein pour la première fois, il y a vingt-neuf ans. Il était venu à Bruxelles assister au congrès Solvay de En se promenant dans les allées du parc Léopold, il me parla d’un article, peu remarqué, que j’avais écrit l’année précédente sur l’expansion de l’univers et qu’un ami lui avait fait lire. Après quelques remarques techniques favorables, il conclut en disant que du point de vue physique cela lui paraissait tout à fait abominable.» 10 ans auparavant, introduction de la constante cosmologique… pour sauver le caractère statique de l’univers <<inspirée par le dogme chrétien de la création, et injustifiée sur le plan de la physique>> Lemaître : « The hypothesis of the primeval atom is the antithesis of a supernatural creation »

8 Einstein (!), Lemaître, Gamow, Hubble
As you know, Einstein will finally join the Big bang Gang I would like now to inquire into the reasons why there is no creationnist commitment in Lemaître’s theory Einstein (!), Lemaître, Gamow, Hubble

9 (1) Energy of constant total amount is distributed in discrete quanta.
« The beginning of the world from the point of view of quantum theory »  Nature 127 (1931) « Thermodynamical principles from the point of view of quantum theory may be stated as follows: (1) Energy of constant total amount is distributed in discrete quanta. (2) The number of distinct quanta is ever increasing. If we go back in the course of time we must find fewer and fewer quanta, until we find all the energy of the universe packed in a few or even in a unique quantum » Despite EDDINGTON’s statement that, « philosophically, the notion of a beginning of the present order of Nature is repugnant » Lemaître inclined to think that quantum theory suggested « a beginning of the world very different from the present order of Nature. » Let us follow some claims of Lemaître’s cosmogony : which could be summed up : « First,there was some thing » (primitive atom) « L’hypothèse de l’atome primitif, un essai de cosmogonie » (1946)

10 In the « beginning » was a single quantum
« If the world has begun with a single quantum, the notions of space and time would altogether fail to have any meaning at the beginning; they would only begin to have a sensible meaning when the original quantum had been divided into a sufficient number of quanta… If this suggestion is correct, the beginning of the world happened a little before the beginning of space and time » !!! Lemaître adds : «  If this suggestion is correct, the beginning of the world happened a little before the beginning of space and time » Which is of course a little paradoxical… So let us put « begin » into brackets Starting point, rather than beginning in the absolute metaphysical meaning.

11 The lecture of 1963 : Universe and atom
« The solution of the differential equations that govern the world obtain  both in letting grow and in letting decrease time. Well, the claim of creation consists in denying that this occurs. But if, at the time of creation, you suppose that the physical laws operate, you may infer which could have been the state of the world before creation, so that a natural evolution from this prewold could have produced the state of the world when created». To sum up, there seems to be a conflict between the naturalist view that physical laws operate at any time, and the view that the world is created at a time.

12 Creation as negation of an extrapolated preworld
« Claiming the creation amounts to saying that this preworld, from which the actual world could have come, is a fiction; that the world was actually created out of nothing; that this preworld did not exist. You can suggest this by saying that creation is not a physical notion » To put it otherwise, the claim for a supernatural creation amounts to suspending the extrapolation towards the past, towards a preworld.

13 A physical beginning of the world
« It is precisely the notion that I think I can take away by suggesting the hypothesis of a physical beginning of the world. My preceding inference rested on the assumption that the world was ever in conditions where the laws of scientific determinism operate. But those laws can break down in many ways» But in order to deny any preworld, you have to give an argument to the stopping, at some point, of the regressive extrapolation towards the past. Which is not at all the same as denying the very possibility of this regressive extrapolation;

14 « Physical beginning» in GR
« First ; the radius of the space grows with time. If it was once, in the Friedman equation, inferior to the equilibrium radius, it is unavoidable that precedently it was smaller and smaller. A naught value of the radius induces a physical beginning. From the zero value of the radius, there are solutions in one direction only.There is no more preworld that could have been the true beginning as well as what we consider as the true one… We would then get a physical beginning that does not deserve anymore the title of creation out of nothing » With the zero value of the radius of the universe, you have no more concurrence between a physical extrapolation to the preworld and a supernatural suspension of the extrapolation : you just get a natural stopping point.

15 « Physical beginning » from the quantic point of view.
« the degradation of energy is bound with its sputtering[…] We should expect that, in the first days of the world, matter was endowed with a much weaker entropy and was, why not, condensated in a few number of packets, or even in one. Then we still come to an evolution that can happen only in one direction, for which the problem of a pre-beginning is pointless, for which the problem of a creation out of nothing is meaningless.  » Lemaître suggests the same point, but from the point of view of Quantum Theory :

16 Last interview (Revue des Questions scientifiques, 1966)
«The beginning of space (of its radius), the beginning of multiplicity is a physical beginning; when inquiring into its nature, you understand that it cannot have any past, that there is no anterior state of affairs that you would have to exclude by saying that it is created from nothing » « Le début de l’espace (de son rayon) et le début de la multiplicité est un commencement naturel; si on en analyse la nature, on comprend qu’il ne peut avoir de passé, qu’il n’y a pas d’état antérieur qu’il faudrait exclure en disant qu’il est créé de rien. Il ne serait donc plus question d’invoquer une action où Dieu perdrait son essentiel incognito, ne resterait plus, suivant le mot du prophète, le Dieu caché, mais s’abaisserait à quelque chiquenaude initiale ou suivant l’expression moins désagréable de Jeans, au " finger of God agitating the ether ". Le problème de la création garderait son sens métaphysique, dans le sens de la dépendance de tout être, de nous-mêmes. Toutes choses ont été faites par lui et rien de ce qui a été fait n’a été fait sans Lui. Mais ce problème serait totalement dégagé de la cosmogonie, de ce fonds étrange de l’espace-temps où s’évanouissent toutes nos notions familières dans l’absolue simplicité. [...] Ce début est parfaitement simple, insécable, indifférentiable, atomique au sens grec du mot. Le monde s’est différencié au fur et à mesure qu’il évoluait. Il ne s’agit pas du déroulement, du décodage d’un enregistrement; il s’agit d’une chanson dont chaque note est nouvelle et imprévisible. Le monde se fait et il se fait au hasard. Tel est du moins tout ce que peut dire la physique ou l’astronomie. Il n’en est pas moins vrai que physique et astronomie n’épuisent pas toute réalité» (G. Lemaître,1966 Revue des Questions Scientifiques, n° 138, 51).

17 Supernatural creation underivable from physics
Talk of supernatural creation requires: 1°) the possibility of the regressive extrapolation towards the past; 2°) an argument to the suspension of this preworld No time → no regressive extrapolation to a preworld → no argument for excluding a preworld → no argument to a supernatural creation . Supernatural creation : privative concept ; you should expect a regression towards a physical past, AND you claim the suspension of the regression But if there is no talk of regression, you are left with a physical beginning, not with a supernatural creation. Even with edges or finite duration, you are not physically committed to a supernatural creation…

18 DISENTANGLEMENT PHYSICAL COSMOGONY≠ CREATION
« Such a theory stays completely out of every metaphysical or religious issue. The materialist remains free to deny any transcendent being» (June 1958, Solvay Congress) « The problem of creation is completely disentangled from that of cosmogony » (1966) Oppose constamment «  création surnaturelle » et « commencement naturel » (pour lequel le problème d’une création de rien est sans signification (pas d’extrapolation possible vers le passé) Incompatibilité méthodologique entre l’application des lois de la physique et l’affirmation de la création : « Si à l’instant de la création, on applique les lois de la physique, on peut en inférer quel aurait pu être l’état du monde avant la création de manière que l’évolution naturelle à partir de ce prémonde ait pu produire l’état du Monde à sa création. Affirmer la création c’est dire que ce prémonde dont le monde réel aurait pu provenir est une fiction. En réalité le monde a été créé de rien, ce prémonde n’a pas existé. On peut exprimer ceci en disant que la création n’est pas une notion naturelle… » (Univers et atome, pp ) « Le raisonnement que je viens de faire repose sur l’hypothèse que le monde s’est toujours trouvé dans les conditions où les lois du déterminisme scientifique s’appliquent. Celles-ci peuvent tomber en défaut de plusieurs manières. Tout d’abord , le rayon de l’espace augmente avec le temps. Si, dans l’équation de Friedman, il a été jadis inférieur au rayon d’équilibre, il est inévitable qu’il ait été jadis de plus en plus petit. Une valeur nulle du rayon de l’espace introduit un commencement naturel . A partir de la valeur zéro du rayon, il n’y a de solution que dans un sens. Il n’existe pas de prémonde qui pourrait avoir été le vrai commencement tout aussi bien que celui qu’on envisage comme un vrai commencement. On obtiendrait donc un commencement naturel qu’il ne serait plus nécessaire de qualifier de création à partir de rien » L’affirmation de la création suspend l’extrapolation des lois de la physique vers le passé. En deçà d’un rayon de l’univers nul, il n’y a pas de physique, donc pas de relève de la physique par la création. « Mais il est un autre aspect de la physique qui conduit par une autre voie à la notion d’un commencement naturel… La théorie des quanta… La dégradation de l’énergie est liée à sa pulvérisation (p. 212). … L’entropie est liée au nombre de quanta. L’augmentation de l’entropie …c’est la pulvérisation de l’énergie. On doit donc s’attendre à ce qu’aux premiers jours du monde, la matière avait une entropie bien plus faible et même pourquoi pas était condensée en u petit nombre, même en un seul paquet. On arrive encore à un commencement naturel avec une évolution qui ne peut se faire que dans un sens, pour laquelle le problème d’un précommencement n’a pas de sens, pour lequel le problème d’une création de rien est sans signification. » (p. 213)

19 25 years later… « There would be no singularities at which the laws of science broke down and no edge of space-time at which one would have to appeal to God or some new law to set the boundary conditions for space-time. One could say: 'The boundary condition of the universe is that it has no boundary.' The universe would be completely self-contained and not affected by anything outside itself. It would neither be created nor destroyed. It would just BE » …. (Hawking 1988 : 136) 25 years later, The picture of a self-contained universe has been suggested by Prof Hawking. But contrarily to Lemaître, Hawking seemed to imply that any boundary or edge of space-time could be crying out for a divine intervention. That is why Hawking welcomes « a new possibility, [opened up by the quantum theory of gravity] in which there would be no boundary to space-time and so there would be no need to specify the behavior at the boundary ». Text one of the most famous claims of Hawking’s Brief history of time [Stephen Hawking, A Brief History of Time (New York: Bantam, 1988), p. 136.] I will not ehter the discussion as to which extent the no boundary model holds I am just considering the point that getting rid of singularities at all cost is a useless precaution against theistic metaphysics. For, first : when studying physics, you should never appeal to God, for God is not a concept of Physics. The famous « finger of God agitating the ether » is a metaphor. When studying physics, you are not dealing with supernatural powers or superguidance of the universe. And second, the inference from a boundary to a creator is not valid in Physics.

20 La The « no boundary, no creation » inference
« So long as the universe had a beginning, we could suppose it had a creator. But if the universe is really completely self-contained, having no boundary or edge, it would have neither beginning nor end: it would simply be. What place, then, for a creator? » (Hawking, 1988: 140) Presuppositions: creation → beginning (temporal boundary); no beginning of the universe → no place for a creator The place for a creator, not a matter of boundary… Let us focus on what I will call the « no boundary, no creation » inference "With the success of scientific theories in describing events, most people have come to believe that God allows the universe to evolve according to a set of laws and does not intervene in the universe to break these laws. However, the laws do not tell us what the universe should have looked like when it started -- it would still be up to God to wind up the clockwork and choose how to start it off. A Brief History of Time (New York: Bantam, 1988), p. 140

21 The true state of the question
…the Question between us and the Atheists is not, Whether the World can possibly have been Eternal? but, Whether it can possibly be the Original, Independant, and Self-Existing Being? Which is a very different Question. For many, who have affirmed the One, have still utterly denied the Other. Samuel Clarke, A Discourse concerning the Being and Attributes of God, 1706

22 Creation : a matter of self-existence, not of timing
Universe is everlasting is finite in time is self-existent has always existed on its own (without any external cause): Epicurus, Lucretius, Spinoza has once existed or just exists on its own (without any external cause) Hume ? Russell ?Hawking ? owes its existence to a cause everlasting effect of a timeless or everlasting God (Neoplatonists, Avicenna, Averroes, Aquinas*, Leibniz…) was created at some point, or at the “beginning” of time (Plato, Augustine, …) Nowadays theologians like Arthur Peacocke or Ian Barbour still claim that the doctrine of the "creation" of the universe is best interpreted as one of the universe's timeless dependence on God, and that such dependence does not demand a temporal creation event. D. Hume, A Treatise of Human Nature, Book I, Part. III, sect. III “Why a cause is always necessary”, ed. L.A. Selby-Bigge, revised by P.H. Nidditch, Oxford, Clarendon Press, 1978, pp , Russell/ Copleston : “I should say that the universe is just there, and that's all”

23 A book everlastingly copied …
Hey, you ! Copycat ! « Let us imagine that the book of the elements of geometry has always existed, one always copied from another; it is evident that, even if a reason can be given for the present book from a past one, from which it was copied, …

24 …nevertheless we shall never come upon a full reason - no matter how many past books we assume - since we would always be right to wonder why such books have existed from all time, why books existed at all, and why they were written in this way.

25 …The library of the states of the world
« What is true of books is also true of the different states of the world; for a subsequent state is in a way copied from a preceding one (although according to certain laws of change). And so, however far back you go to earlier states, you will never find in those states a full reason why there should be any world rather than none, and why it should be such as it is. » Leibniz, On the ultimate origination of things (1697) Two separate questions Given such and such physical state of affairs, what are we likely to infer from the data ? Where does the universe come from? Why is there a universe (eventually self-contained ?)

26 Therefore, even if you should imagine the world eternal, because you still suppose only a succession of states, and because you will not find a sufficient reason in any of them, and indeed no matter how many states you assume you will not make the least progress towards giving a reason, it is evident that the reason must be sought elsewhere. The universe at t t t t t t t to

27 Self explanation vs theistic explanation
« Even if there is only one possible unified theory, it is just a set of rules and equations. What is it that breathes fire into the equations and makes a universe for them to describe?... Why does the universe go to all the bother of existing? Is the unified theory so compelling that it brings about its own existence? Or does it need a creator, and, if so does he have any other effect on the universe? And who created him? » (Hawking 1988, 192)  As a matter of fact, Hawking did know that the no boundary condition was not sufficient to get rid of a creator TEXT : Even if there is only one possible unified theory, it is just a set of rules and equations. What is it that breathes fire into the equations and makes a universe for them to describe?... Why does the universe go to all the bother of existing? Is the unified theory so compelling that it brings about its own existence? Or does it need a creator, and, if so does he have any other effect on the universe? And who created him? (A Brief History of Time (New York: Bantam, 1988), p. 192) Cf The taxi cab objection Once the existence of the First Cause is inferred, the PSR is dismissed, like a taxi after it has brought us to our destination, instead of being applied to the First Cause or its creative act. Why should God constitute a better explanation for the existence of the universe, than… a self-existent universe ? A good starter for a metaphysical inference to God : « the universe is not One thing, but many things »

28 , The Great Design, 2010 X creates itself from nothing ? (A) Given « nothing » at all, X spontaneously brings it about that… X exists (B) Given « a law such as gravity », and some X on which it operates… physical explanation  selfcreation from nothing  Anyway, I do not suggest that it is necessary to invoke God There is no contradiction in the conjunction : the universe simply is, and there is no God Nevertheless, God (a supernatural agent) might provide a metaphysical explanation – not a scientific one - of the very fact that there is something rather than nothing. Let us turn to consider Hawkings more recent Great Design Because there is a lawsuch as gravity…

29 “Science is incompetent to reason upon creation of matter itself out of nothing” (J. C. Maxwell,“The Molecules”, 1873) de collisions de photons ou de rencontres particule/anti-particule,

30 « The problem of creation retains its complete metaphysical meaning, the meaning of the dependence of every being, of ourselves. […] Physics and astronomy do not exhaust the whole reality » (1966) To conclude : we cannot conceive of any physical transtion from absolute nothingness to any physical state of affairs, for absolute nothingness is not a physical concept. (it is rather a concept of the non-physical) Even in metaphysics this transitional account of creation meaningless. First there was nothing, then there was something is but an image, due to narrative constraints. A spatio-temporal boundary of the universe is not a necessary condition for its being eventually created. Lemaître has displayed an interesting argument to the claim that it is not even a sufficient condition, for the kind of « beginning » it provides the universe with cannot be contrasted with a supernatural creation : it is an internal affair of physical development. And a development from a radiusasymptotically tending to zero , or from a primeval atom, is not a development from nothing. Lemaître considered that the physical universe could be endowed with a physical or natural boundary that precludes any physical discussion as regards what could take place before or beyond the edge of space-time. For if there is neither place nor time, there is neither before nor beyond It is a starting point for physics, not an abolsute metaphysical beginning. But this physical starting point neither implies, nor precludes any l relation of ontological dependence, which is a better concept of creation. To this extent, Lemaître is a great promotor of the Non Overlapping of Magisteria, a very careful scientist, and by the way a good metaphysician.