Monday, July 26, 2010

Should the reigns of the question of origin of the universe be a proprietary subject addressed by science?

"The Origin of the Universe and Contemporary Cosmology and Philosophy"


Jan Such


Since the 1970s both in physics and cosmology, there has been a controversy on the subject of the ‘beginning of the universe.’ This indicates that this intriguing problem has reached scientific consideration and, perhaps, a solution. The aim of this paper is to try to answer the question as to whether the origin of the world has slipped out of the hands of philosophers (and theologians), and passed in its entirety into the realm of science, and whether science is able to solve this problem by itself. While presenting the main views in this dispute, I try to show also that metaphysics, philosophy of nature and epistemology provide important premises, proposals and methods that are indispensable for a solution. These premises concern such issues as the extremely subtle problem of the sense and existence of ‘nothing,’ the problem of extrapolation of local physics onto the large-scale areas of the universe, the epistemological status of cosmological principles, as well as problems of the origins of the laws of nature. This last issue is entangled in the difficult problem of the ‘rationality of the world’ and the problem of overcoming the dichotomy of laws and preconditions, according to which the conditions and laws are independent of each other.

I. Introduction

One of the determinants of scientific rationality is the condition that science undertakes only those problems whose solution is within the range of possibilities of research methods which science currently applies or is able to apply. Simply speaking, scientists are attracted by solvable problems. If this is really so then the fact of widespread discussions since the 70s among physicists and cosmologists on the subject of "the beginnings of the Universe" seem to be an obvious sign that also this unusually intriguing problem has matured to its scientific solution.

The purpose of my paper is to attempt to answer the question whether the problem of the origin of the world currently evades philosophers (and theologians) and passes completely to the realm of science (i.e. physics, astronomy and cosmology), or whether science by itself is not able to solve this problem. In the latter case one would have to acknowledge that metaphysics, the philosophy of nature and epistemology, provides important premisses, assumptions and methods indispensable for this solution.

II. Two Approaches in Cosmology

The task cosmology has to perform is to explain the structure of the Universe as it is observed. Contemporary cosmologists carry out this task by means of two, to some extent contradictory, approaches. One wants to explain the structure of the Universe observed through what the Universe was at the very beginning; the other, on the other hand, tries to show its present structure as an inevitable consequence of past physical and chemical processes, irrespective of what was at the beginning. A permissible possibility here is that the Universe is so constructed that no observable traces of its quantum origin remain. The Theory of the Big Bang in its classical, purely relativistic interpretation, is an example of the former approach. However, its inflational development which refers to the physics of high energies and to quantum mechanics is the fullest expression of the latter approach. Irrespective of how the Universe began (and whether it began at all) that which we observe at present on a cosmological scale is the result of an extremely short period of inflation in which, due to the unparallelled intensity of extension at an exponential rate, it was transformed from a microobject (with respect to its spatial dimensions) into a macroobject.

Obviously to solve the problem of the origin of the world, of fundamental importance is the former approach which assumes that further evolution of the Universe did not preclude the significance of its initial states for what we observe now on a large scale.

It does not mean that the prevalence of inflational models in modern relativist and quantum cosmology renders cosmology incapable of dealing with questions of the origin of the Universe. It is only in recent years that scientists have concentrated on the former approach. There has been a search for fundamental laws which would determine the initial conditions of the Universe.

III. Dichotomy of Laws and Initial Conditions

In classical physics (and in general, in the modern approach to explanations of phenomena) a principle of dichotomy of laws and of initial conditions. According to this principle initial conditions (understood as conditions in which laws may be applied) are totally independent of the laws of nature, in the sense that from the point of view of laws their distribution is completely random.

Quantum mechanics seems to be the first theory which began to threaten this dichotomy. According to Heisenberg's principle of indeterminacy initial conditions of a mechanical system (i.e. position and velocity) are canonically joined and as such cannot at the same time be determined with optional precision. This imposes certain restrictions on the distribution of these conditions and leads as is well known, to the undermining of the so-called Laplace determinism which respected the principle of dichotomy.

In modern cosmological considerations concerning the earliest stages of the Universe the problem of dichotomy of laws and conditions is given first-rate significance. As it is the problem of the beginnings of the Universe may not be solved in any way without shaking this dichotomy.

IV. In the Search of a New Type of Laws

In reference to the initial state of the Universe one should consider critically the view that initial conditions are independent of the laws of nature. One might assume that the Universe is exceptional in the sense that it is the only nomologically coherent possibility. This means that the initial conditions are also exceptional and through this become a law of Nature themselves ("a superlaw"). Another possibility is that the universe is genetically unlimited, i.e. is a Universe "without boundaries".

This kind of approach leads to the search for a new type of laws. These would not be the laws which determine a permissible change of the state of the world between one moment and another, but laws which rule very initial conditions.

The traditional view, based on the dichotomy of laws and conditions as applied to the Universe was often associated with the view that theologians deal with initial conditions and physicists deal with the laws of evolution. However, contemporary cosmologists try to establish whether there are any laws of initial conditions which would overcome randomness of their distribution. Studies divide into two directions.

V. World Without Borders

The first one, which is more radical, is the Hartle-Hawking conception of the world without borders. A suspicion that time and space are not universal characteristics of the physical reality, sometimes formulated in microphysics, have been strengthened in this conception but only as far as time is concerned, and transformed into an assumption that in Planck's era given extreme densities under which quantum effect dominate time loses its properties which differentiate it from space. First of all it stops being anisotropic, stops running in a given direction. It means that the initial quantum state is actually a timeless state and that there had been nothing "before" the beginning of the Universe since "then" there was no time. As a result, in Planck's era the Universe behaves as a four-dimensional hypersphere (surface of a ball). In this manner "the condition of not occurring of a border" makes it possible to avoid the singularity of the initial state. On the other hand, the ordinary character of time as qualitatively different from space begins to crystallize in the first moments following Planck's era. Therefore, we can see how the question on the beginning of the Universe leads to the question of the nature of time itself.

Conception of time which becomes space — to be more exact still another (fourth) dimension of space — is one of the most innovative ideas of modern cosmology. The condition of non-occurring of the border shifts the whole "responsibility" for the origin of the Universe onto the laws ruling the Universe (and possibly onto their source, e.g. in the form of a Lawgiver). In this way the question of dychotomy of laws and conditions is settled through total subjection of initial conditions to initial laws, even at the cost of liquidating initial conditions as such.

The solution for this dychotomy assumes another form in the other direction of studies.

VI. Creative Conceptions of the Universe

This is a direction which contains various conceptions of the creation of the Universe (1) out of "nothing" or (2) out of a "vacuum". However, at least one of these conceptions solves the problem of dichotomy in a similar manner to the conception of the lack of borders. This is a view that our Universe is exceptional in the sense that it is the only (logically or nomologically) cohesive possibility. This leads to the conclusion that also the initial conditions could not have been different from what they were. In this interpretation the role of conditions is as if reduced to the role of laws, so that the conditions themselves become law (or laws) of nature. (Let us notice that in this respect at the extreme end of cosmological views there is a conception of a multitude of universes, according to which there is an infinite number of worlds in which all possible conditions are realized. This conception does not, therefore, undermine the classical dychotomy of laws and conditions.)

However, a vast majority of conceptions of creation assume that our Universe, in which conditions arose for the existence of "a conscious observer", due to its insignificant a priori probability is — from the point of view of laws which we know — only one of many possible universes. Therefore, even if the initial conditions are not totally independent of laws still the latter do not determine them unequivocally. In the conceptions discussed the problem of the description of initial conditions is reduced to giving characteristics of from what the Universe arose.

From the point of view of philosophy what is significant is the division of creative conceptions into those which assume that the Universe arose from "nothingness" in the strong ontological meaning of the word and those which lead to the conclusion that it was originated from a certain "poorer" physical reality, usually called "a vacuum" or space-time. Both kinds of conceptions usually refer to quantum mechanics or the future quantum theory of gravitation which is to combine quantum mechanics with the general theory of relativity.

VI.1. Creation from "Nothing"

Supranatural conceptions of creation out of "nothing" which refer to God are well-known to us in European philosophy and Christian theology. In cosmology the first conception of creation out of nothing appeared and was promulgated already on the grounds of the relativist theory of the Big Bang, especially after 1970 when Penrose and Hawking proved their famous theorem on singularities. It could be seen from these theorems that if there is a sufficient amount of matter in the Universe and gravitation always and everywhere attracts, then the extension of all light rays back in time, to infinity is impossible. This meant that (at least some) time lines break at the moment of the Big Bang, or in the primary cosmological singularity.

It could be interpreted as the rise of matter, time and space out of "nothing", therefore, as "a beginning of the world and at the same time the beginning of time". In this interpretation the world does not arise in time, but together with time (which recalls St. Augustine's conception). However, since the general theory of relativity could not give any "mechanism" of transition from "the state of nothingness" to "the state of existence" of the Universe, further conceptions of creation out of "nothing" began to adduce quantum mechanics. This theory describes at least two processes which may compete for the name of "creative processes" which rouse the interest of cosmologists. These are phenomena of "quantum tunnelling" and of "quantum fluctuation" which occur due to quantum effects; consequently are impossible from the point of view of classical physics.

In the conceptions of creation out of "nothing" the former phenomenon is mostly used. "Tunnelling" in its common quantum interpretation is overcoming certain energetic potentials by microobjects whose energy resources are lower than the necessary minimal energy if the process is to be interpreted in the light of the unexceptional laws of classical physics.

In quantum cosmology the "tunnelling out of nothing" is discussed. When an analogy with the effect of quantum tunnelling is made a mathematical description of the process in which the Universe together with time and space emerges out of nothingness, described in the language of mathematics by an empty set. One cannot speak here about tunnelling in the strict sense of the word, since such a claim would assume the existence of two different physical states. In the meantime, the process postulating the creation out of nothingness reveals that one cannot determine any earlier states of the emerging Universe since no prior external time exists, previous in relation to the time which appears together with the world.

If we apply Schrödinger's equation defining the wave function in ordinary quantum mechanics for the whole Universe so that it also takes gravitation into account (the space-time curvature) then the Wheeler-De Witt equation is obtained which is called "the wave function of the Universe" U. In this way the function T [x1, t1 ---> x2, t2] gives the probability of finding the Universe in state x2 at the t2 moment, if at the previous moment t1 it was in the x1 state. One of the possibilities consists in this that, according to functions U and T the Universe tunnels to the state of existence out of nothing with a definite probability. In other words, there is a certain probability of transition which has such a form in which there are no previous initial states. According to this scenario there is a certain probability of a spontaneous appearance of the Universe of a definite type together with a definite time and space, created out of nothing.

However, there is a fundamental question: Can nothingness (total nothingness in the strong ontological sense) exist at all from the point of view of the laws of physics? This doubt does not relate to the conception of creation out of a "vacuum".

VI.2. Creation out of a "vacuum"

A well-known fundamental metaphysical question is: "Why is there rather something than nothing?" which led great philosophers of various times (Aristotle, Leibniz, Heidegger) to grapple with the basic philosophical problems. It assumes the sensibleness of the concept of "nothingness".

The question of the sensibleness of this concept is conspicuous in quantum mechanics and in the quantum theory of the field, extended around quantum electrodynamics. Sometimes a conclusion is drawn from Heisenberg's principle of uncertainty that a "vacuum" (in the sense of something devoid of any substrate or any physical properties) is impossible since its existence would allow exact establishing of the value of the canonically joined values, e.g., position and velocity.

The quantum field theory (and attempts at creating of the quantum theory of gravitation made on these grounds) interpret vacuum not as a nothingness, but as an extremely active arena which through "fluctuation of a vacuum" constantly creates virtual particles of all possible kinds. Vacuum in this interpretation has not much in common with the philosophical concept of "nothingness", but constitutes a kind of active time and space endowed with various physical properties (which are usually divided into topological, metrical and properties of symmetry). On the other hand, the dynamic character of the vacuum (time and space) signifies that it is also apportioned with energy.

Conceptions of the creation of the Universe out of "vaccum" assume that it arises in the process of "fluctuation of vacuum", and therefore it is created not out of nothing, but out of a certain physical reality, poor in properties and called a "vacuum".

Some of the conceptions of this type, e.g. J. Wheeler's conception, impoverish even more this initial reality of which the Universe was to emerge. They assume, for instance, that time as such is a complex structure which consists of simpler elements. Assuming that these elements "went into the composition" of time at the moment of the rise of the Universe we obtain a conception according to which time is created together with the Universe, but it is created not out of nothing, but is preceded by certain elements of physical reality (this brings to mind the conception of "the world without borders" where time in Planck's era also loses some of its characteristics or, in other words, becomes impoverished). Following this line of thinking one could imagine that our Universe was not formed in one act of creation, but in a number of such acts, e.g. first out of nothing (in the literal sense) elements of time and space had been created (pregeometry) which then formed space-time ("vacuum"), and then out of vacuum the Universe was created (which in the course of further development may be enriched with new essential ontological characteristics and so on without end).

VII. Conceptions of the Universe which is Infinite in Time

Not all conceptions which deal with the origin of the Universe negate its eternity; it is not negated by (1) A. Linde's conception of a chaotic inflation, (2) the conception according to which the Universe suddenly starts an expansion from the solid state in which it rested for an infinite period of time in the past, (3) the conception which assumes that the Universe was smaller and smaller in the past, however, never achieving zero dimensions and some others.

VIII. Cosmology and Philosophy

Let us go back now to the main problem of my paper: Has the beginning of the Universe become a strictly scientfific question, i.e. such that science is able to solve it itself ?

A partial answer to this question can be given by consideration of the cognitive status of these conceptions which assume the creation of the Universe out of "nothing".

So, the concept of nothingness itself and the assumption that nothingness is possible, is a philosophical concept and a philosophical assumption, which goes much beyond that which can be established by scientific research as such. The latter reaches at most the concept of a vacuum which, as can be seen, is by no means identical with the concept of nothing (in the philosophical sense). That which is understood as vacuum in physics and cosmology is apportioned with essential physical properties, and deserves rather the name of space or space-time than that of nothing.

The fact that in these sciences at least several concepts of vaccum are used ("absolute vacuum", "relative vacuum"; "false vacuum", "true vacuum" etc.), and that actually this concept is relativized to the concrete physical theories does not change anything (e.g. the absolute vacuum is not nothingness in the philosophical sense either). Similarly, the theses on the creation of the Universe out of "nothingness", on "tunnelling out of nothingness", "fluctuation of nothingness" and the like are not purely scientific theses. These kind of theses and conceptions which they contain must assume as a basis much more than that which corresponds to the philosophical (and also the everyday) understanding of the concept of nothingness. If one omits energy, mass and even geometry (chronogeometric properties) as characteristics not of nothingness, but of the active (dynamic) space-time then one should recognize that "at the very beginning" there must be laws of nature, according to which "nothingness creates the world", which also assumes the existence of something that can be called the world of logic and mathematics. In this sense explanation of the origin of the Universe cannot do without an assumption of some structure of rationality.

Perhaps this assumption may not lead by itself to theology, but seems to lead inevitably to philosophy. Perhaps physics is able to explain both the origin, the order and content of the physical Universe, but not of the laws of physics themselves. There must exist laws of quantum mechanics if quantum processes are to lead to the rise of the Universe. From this point of view, open to critical analysis is S. Hawking's conviction in which elimination of all questions about the so-called boundary of time and space, which has its own place in his conception, signifies as if automatic exclusion of problems which as a rule led to religious and philosophical comments. From the philosophical point of view the conception of the non-existence of borders shifts the problem of the source of initial conditions to the question of the origin of physical laws, according to which the Universe does not have borders.

Another reason which indicates an inevitable involvement of the question of the beginning of the Universe in philosophy is that cosmology as an empirical science is entitled to make statements on the structure and evolution of the observable part of the Universe, but not on the Universe as a whole. In turn, constraints on our scientific knowledge about the Universe to its observable part (called the horizontal Universe) mean that we are not able to check scientifically the correctness of a rule for initial conditions (or their lack) for the whole Universe. After all we observe results of evolution of only some part (indeed a very small one, which is confirmed by conceptions of inflation) of the initial state.

However, it can be seen from this that extrapolations of local physics onto the whole observable Universe cannot do without cosmological principles, about which we know are basically of a philosophical character. Still extrapolations of this kind conducted in cosmology are insufficient to make their conclusion pertaining to the Universe, understood as the whole physical Universe.

One more reason of the inevitability of philosophy in cosmological considerations is that the outcome of cosmological statements, also those that are essential for the solution of the question of origin of the Universe, may be interpreted differently, and that in the process of this interpretation an important role is played by philosophical assumptions, both ontological and epistemological (as well as those which are not connected with cosmological principles). Great significance of interpretation in cosmology is emphasized by circumstances that while macroscopic physical theories such as classical mechanics — due to their relative "closeness" to experiment — have the so-called natural interpretation (which generally does not rouse any doubts) microphysics and cosmology theories may be interpreted in many different ways. Proof of this are numerous and extremely different interpretations of quantum mechanics on the one hand, and the multitude of interpretations of the shift to the red in galactic spectra, the multiaspectual dispute over the nature and distance of quasars or different interpretations of the initial singularity, on the other hand.

Hawking's criticism of metaphysics seems to be a little bit outdated because it combines in itself elements of positivist philosophy of cognition with the conception of God, shared by Clark in the 18th century, filling in the gaps in natural science.

In connection with the occurrence in cosmology of numerous, and at the same time significant, philosophical and methodological assumptions which cannot be verified empirically without which it could not function as a science, cosmology may be considered as "science not only of the Universe in its largest scale, but also about assumptions which one should form in order to make such a science possible".

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