The Enigma Of The Universe : The Reality of Space-time

The second aspect of the theory of the relativity is regarding the reality of space and time. We have already seen that all the scientists are not unanimous regarding it. Whereas Einstein, Jeans etc. consider space and time as merely the intuition of consciousness, Reichenbach, Heisenberg etc. do not deny their reality to reach some definite conclusion. First of all it is necessary to clearly understand some scientific concepts, such as space, time, four-dimensional continuum of space-time, gravitational field, metrical field, ether etc. It will be also fruitful to know their relation with the Jain metaphysical concept of 'ākāśa', time, Dharma and Adharma Dravyas.

Einstein, and other scientists mean by space an 'order of things', whereas Reichenbach etc. conceive space as an independent reality, besides such an order; the Jain metaphysics define ākāśa as an objective reality or real substance giving room to other substances. This concept of Jain metaphysics is quite different from the Einsteinian concept. But if we accept the Einsteinian concept, the problem of the substratum of the substances is not solved. We, therefore, on the logical grounds, have to abandon the Einsteinian concept; moreover the Einsteinian definition is not sufficiently clear. For the general theory of relativity unifies space with the gravitational field or the metrical field. Then space no more remains a mere order of things but takes the form of some reality or field which has curvature. Now the question is whether this field is an independent reality? If the answer to this question is not in negative, then this field would be probably not much different from the 'real space', i.e. ākāśa.

It is generally believed that such a field or curvature is generated only due to the presence of the mass of the substances. That is to say anything possessing 'mass' creates a gravitational field around itself, just as a magnet creates a magnetic field or an electric current creates an electromagnetic field around it. If this is so, the gravitational field cannot be considered as an independent reality. But this is not strictly true, for even in absence of matter or mass, there exists a sort of residual curvature or field in the space. This is clearly expressed by Sir Arthur Eddington, the renowned physicist, thus; "In a region where there is no recognised matter or electromagnetic field, there is still a certain small natural curvature, viz., that specified by the famous 'cosmical constant'. The mass, momentum and stress equivalent to this curvature ought therefore to be ascribed to whatever we suppose to occupy such a region, i.e., to the space, field or ether whichever term we are using." ^[1]

Here, we quote his view:^[2] "As far as and beyond the remotest stars the world is filled with aether. It permeates the interstices of the atoms. Aether is everywhere.

"How dense is the aether? Is it fluid like water or rigid like steel? How fast is our earth moving through it? Which way do the particles of aether oscillate when an electromagnetic wave travels across it? At one time these were regarded as among the most urgent questions in physics; but at the end of a century's study we have found no answer to any of them. We are, however, convinced that the unanswerableness of these questions is to be reckoned not as ignorance but as knowledge, what we have found out is that aether is not the sort of thing to which such questions would apply Aether is not a kind of matter. Questions like these could be asked about matter but they could not be asked about time, for example; and we must reckon aether as one of the entities to which they are inappropriate.

"Since aether is no material it has not any of the usual characteristics of matter-mass, rigidity, etc.-but it has quite definite properties of its own. We describe the state of the aether by symbols, and its characteristic properties by the mathematical equations that the symbols obey.

"There is no space without aether, and no aether which does not occupy space. Some distinguished physicists maintain that modern theories no longer require aether-that the aether has been abolished. I think all they mean is that, since we never have to do with space and aether separately. we can make one word serve for both; and the word they prefer is "space". I suppose they consider that the word aether is still liable to convey the idea something material. But equally the word space is liable to convey the idea of complete negation. At all events they agree thus in employing an army of mathematical symbols to describe what is going on at any point where the aether is-or, according them, isn't. "Whosesoever the carcass is, there will the eagles be gathered together", and where the symbols of the mathematical physicist flock, there presumably is some prey for them to settle on, which the plain man at least will prefer to call by a name suggestive of something more than passive emptiness.

"Those to whom the word space conveys the idea of characterless void are probably more numerous than those to whom the word aether conveys the idea of a material jelly; so that aether would seem to be the less objectionable term. But it is possible to compromise by using the term "field". The field includes both an electromagnetic field and a gravitational or metrical field; and the army of symbols to which I have alluded describes these two fields. Space (in its ordinary physical meaning) is the same thing as the metrical field; for the symbols describing the metrical field specify the one characteristic that we are accustomed to ascribe to a space, viz., its geometry (Euclidean or non-Euclidean). In specifying the geometry they specify also the field of gravitation, as Einstein showed in his famous theory. We recognise that there is an inner unity of the electromagnetic and the metrical (gravitational) fields and the mode of bifurcation of the single unified field into these two component fields is, I think, fairly well understood.

"The change in our conception of the world wrought by the aether or field theory may be illustrated by an incident not infrequent in astronomical observatories. A visitor is handed a photograph of some interesting celestial object. He is puzzled; he turns it this way and that; but he cannot get the hang of the thing. At last the astronomer sees what is the trouble-"I should have explained. This is a negative. The dark markings constitute the object; the bright part is only background". The visitor mentally turns the picture inside out. Our familiar picture of the world is the aether really stands for. Early electrical theories focused attention on an electric fluid flowing along a wire and treated the space outside the wire as mere background. Faraday taught us that, if we would understand the phenomena of electricity, the supposed background-the field outside the wire- was the place to attend to. If you can make this reversal of the picture, turning space from a negative into a positive, so that it is no longer a mere background against which the extension and the motion of matter is perceived but is as much a performer in the world drama as the matter-then you have the gist of the aether theory whether you use the word "aether" or not.

"The reversal of the picture is liable to be carried too far. After the great development of the field theory of electromagnetism by Faraday and Maxwell, attention was brought back to the more material aspect by the discovery of the electron and the development of electron theory by Lorentz and Larmor. This reaction in its turn has probably proceeded too far, and it would be a gain if the field aspect were more emphasised. But by gradually diminishing oscillations we are drawing nearer to a unified field-matter theory in which neither the field nor the matter is mere background, nor one is seen to be the necessary complement of the other."

This quotation makes it clear that even in complete vacuum there exists something which we have to consider as an independent reality. The Ākāśa of Jain metaphysics may be even different from this. The twin ethers Dharma and Adharma seem to be responsible for this natural curvature of space. Though we cannot say anything certainly about this, at least it becomes clear that the Einsteinian definition of space falls short in this respect. Also the above discussion makes it clear that the concept of 'Ākāśa' which is given by the Jain metaphysics is not fulfilled by the concepts of space, ether or field of the modem physics.

Now we shall consider the curvature or field, which is different from the natural curvature denoted by 'the cosmical constant, and which is created by the masses. The general theory of relativity proposed by Dr. Einstein is supposed to replace the Newton's Law of Gravitation by its Law of Curvature of Space. According to this law, the properties of space or even the existence of space depends upon the material bodies and energy or masses that are present. Where there is a mass, field or space is generated around it. If the mass is removed from that place, the field or space is also removed. In other words, as said before, this field is connected with the mass in the same way as the magnetic field is connected with a magnet. The philosophical interpretation of this phenomenon would be that a gravitational field or metrical field is essentially an attribute of matter and not an independent reality in itself. Hence it is clear that the realities represented by Ākāśa, Dharma and Adharma of the Jain metaphysics are quite different from this gravitational field produced by a mass.

Next we shall consider the concept of four-dimensional continuum of space and time. This Einsteinian concept is a bit difficult to understand. As said before Einstein, Jeans etc. consider it not to be an objective reality. The universe, in their view, is nothing but a four-dimensional continuum of space and time.^[3] Also, they believe that the universe consists not of things but of events and that these events are the various modes of the four-dimensional continuum of space and time. Such a picture of the universe is certainly quite confusing. On the one hand it is believed that the matter causes curvature in the four dimensional continuum. This belief is clearly expressed in the following analogy: "Just as a fish swimming in the sea agitates the water around it, so a star, a comet, or a galaxy distorts the geometry of the space-time through which it moves."^[4] On the other hand all these objects which constitute the universe are taken to be the modes of the four-dimensional continuum itself. Such ambiguous concepts have weakened the philosophical or more precisely the metaphysical aspect of Einstein's theory. Contrary to this, Reichenbach's concepts are quite clear. He accepts the fact that space, time and matter are related to each other, but at the same time he does not deny their independent existence. Also it is his clear view that calling time a dimension of space on the basis of the concept of the four-dimensional continuum would be wrong; he remarked "whereas the conception of space and time as a four-dimensional manifold has been very fruitful for mathematical physics, its effect in the field of epistemology has been only to confuse the issue. Calling time the fourth dimension gives it an air of mystery."^[5] He concludes: "We may therefore retain the perpetual difference between space and time without fear of contradicting the mathematical representation. The properties of time which the theory of relativity has discovered have nothing to do with its treatment as fourth dimension."^[6]

The Jain metaphysical concepts are more logical and clearer than Einsteinian concepts. By accepting the Pudgala (i.e., matter), Ākāśa, (i.e., space) and Kāla (i.e., time) as independent substances, the Jain theory does not seem to contradict the theory of relativity. The Jain view is that the material attributes of Pudgala such as mass, motion etc. should have no effect on the structure of Ākāśa. On the basis of the Jain concept, it can be said that the gravitational field etc. generated by the matter or material effects should be material and hence the changes, modifications brought about thus also should be connected with matter and not with space.