Our conception of what is possible, and what should be discarded as impossible depends largely on our perception of the universe as well as the range of our observations. It is equally true whether we indulge in a statistical analysis of limited scope, or natural philosophy encompassing the entire cosmos. Even in a scientific analysis, the direction and scope of investigation is defined by the chosen or stipulated constitutive equations and the observed boundary conditions. In fact, perception and conception are considerably more interrelated than we usually realize. Imagine the consternation of a robotic visitor from outer space on earth whose range of perceptions is limited to solid inorganic materials such as rocks and metals. Not being able to see the human beings, animals and trees and plants he would be wondering about the important role wrist watches, rings, buttons, buckles, shoe-nails, ear-rings and lockets play in the running of the mechanical systems on the earth. He is bound to be surprised at the observation that the arrival of keys and other trinkets brings automobiles to life, and the accumulation of a number of vehicles in the vicinity of a building and the movement of trinkets, especially nibs close to large machines causes great mechanical movements and production. Eventually, even if our visitor develops the means to detect the existence of fruit and vegetable, not being able to perceive those who consume them, he might wonder if there are holes in space into which things disappear. And, of course he would be convinced of the existence of dark invisible matter. If he persists in his investigations rather than making an escape from this baffling place, after some time he would come to believe that there exist on earth, life forms that he is unable to see, although in some ways he can feel their presence. Similarly, over the centuries mankind has come to believe in the existence of invisible forces that influence its existence.
The fact that modern physicists have accepted the existence of massless particles that transport energy and momentum or electrons making quantum leaps in privileged orbits definitely has roots in thousands of years of belief in spirits and genie, if not exactly a case of substituting superstitions. So let us, briefly, go through the history of the development of the concept of the physical universe, and see if the divergent views can be unified to achieve a globally acceptable model that obviates the need to turn a blind eye to certain undeniable facts. The most significant and trying question in such an analysis is: Where to start? There are many ancient mythologies which present some sort of a model of the universe that can be interpreted variously by the substitution of terms to indicate the probable intention of the author in contemporary vocabulary. The Greek, Chinese and Indian ancient religious traditions, to name the best known, have their own romance and socio-spiritual utility for those who choose to adopt them. They might even be distorted expressions of Divine revelations. However, none of those has produced an offshoot that could be recognized as a movement towards sustained intellectual or scientific development leading to the present day state of affairs; although their occasional or indirect contributions can not be denied. Let us, therefore, start with Democritus, the fifth century BC Greek philosopher who is generally credited with the discovery of the Atom.
The work of Democritus is summarized by Giorgio de Santillana in the following words:
"In order to rescue phenomena and have them reveal a rational reality, Democritus projects it, on two levels. Space is one, and matter is one, too, and events are due to the changing dispositions of matter in space. Empedocles had apparently disregarded (if it had ever reached him, for there is a question of dates, too) the sharp reasoning of Zeno, which led from total divisibility to the irrelevance of physical matter. Democritus was mathematician enough to acknowledge its full impact. This led him to dispose once and for all of the equivocation about particles going into the smaller and smaller, by posting firmly a threshold of divisibility. Hence we must conceive of matter as composed of mobile elements, all of the same substance but of different forms and sizes; small enough to bring forth the many things of this world only by aggregating and coming apart, and also small enough to remain themselves unbroken or "undivided" in the turmoil, as are the grains of sand on a wave laden beach. "Undivided" is the Greek `atomon', and it is thus that the key image of modern physics makes its appearance.
Since atoms are the only reality, they move in what must be emptiness, and so that other key idea, the "void" has been brought in. The universe, until then, had always been thought of as being full, were it only, as in Parmenides, "Being full of Being", the abstract density of the true continuum which was also in some way the body-of-the-world. Here the dichotomy is completed; we have the continuum become what it truly was from the start, geometrical empty space, and in it the one matter, conceived on its part as "wholly full" and compact; but that matter has nothing but geometrical properties itself, derived from space. It has "size, shape, position and velocity". Nothing else is needed to describe the atom".
He goes on:
"The extant scientific fragments of Democritus, as we have said, are miserably few. But each one of them goes straight to the heart of the matter:
"Nothing comes about perchance, but all through reason and by necessity. [This is already attributed to his master Leucippus.]
Nothing can be created out of nothing, nor can it be destroyed and returned to nothing.
There is no end to the universe, since it was not created by any outside power.
By convention color, by convention sweet, by convention bitter; in reality nothing but the atom and the void.""
The atomic theory has already been developed and expanded to very useful limits as we shall see in subsequent discussion. The question as to whether the universe is limitless or finite will be answered in time. If the universe is finite then light must be reflected from its boundaries and it should be possible to observe and identify reflected images of stars and galaxies through the advanced techniques of sky mapping already developed and being used by astronomers. In fact, the identification of reflected images should help to determine the exact dimensions of the universe. If the Universe is finite then the actual number of galaxies that can be seen through telescope may not be as high as it seems. We might just be seeing multiply reflected images of the same galaxy or galaxies at different times in antiquity. The more powerful a telescope the fainter and older image it would show and it would appear to be farther away. One day we may develop a telescope strong enough to show the picture of the universe as it was “in the beginning.”
Could our hollow universe be nothing more than an air pocket in a very large casting? The ultra-simplistic binary concept of the atom and the void also had to be modified when Democritus realized that there would have to be an innumerable variety of atoms in order to account for the diversity in the properties of the materials that exist. The atheism propounded by Democritus seems to be a logical extension of the intellectual movement proceeding from the mythological polytheism to Anaximander's monotheism, which was interpreted by his scientific mind more or less in the same way as some of the twentieth century scientists. The rejection chain syndrome! It is also a typical example of the fact that whenever the possibility of a change in the status quo arises, everyone tries to mold the situation according to his or her own thinking or whim.
In the very next century, an even more formidable intellectual juggernaut, Aristotle came forward with a far more eloquent rebuttal of the ideas put forth by Democritus. His package included a summarization of all existing philosophy regarding cosmology, physics, mathematics, biology, sociology, religion, and literature; augmented by his direct observations on biology and the four element (earth, water, air and fire) theory of the composition of matter. If we interpret earth, water, air and fire as the primitive concepts of the states of matter -- solid, liquid, gas and radiant energy -- then the void would contain a certain amount of rarefied gases and radiant energy; whereas on earth there would be various varieties and combinations of each of the four basic forms. It is such a pity that none of his contemporaries nor followers tried to reconcile the two and suggest that the three states of matter could have atomic structures. Giorgio de Santillana sums up the universe model of Aristotle as follows:
Quote:
"Plato had made it very clear that true knowledge is divorced, "cut off" as he insists, from sensible reality, whose symbol is the dark wall of the Cave. Between the two worlds there is only geometry to join them, myth, and the wings of Socratic Eros, of which we are told in the Symposium. For Aristotle, the Ideas are inherent in the individual substances; they are nowhere else to be found and known, except in the Active Intellect of God who thinks them forever and thus causes the world to function. But if there is nothing but physical substance, it must extend all the way to the upper limit of heaven, and be such as to account for the geometrical behavior of the stars. There will be rigid spheres, hard, transparent, crystalline, to carry the celestial bodies. The abstract mathematical models of the astronomers (of which hereafter) are transformed by Aristotle into an absurd machinery of crystal spheres turning and counterturning so as to cancel out all except the one driving 24-hour motion, that of the outer heaven or Primium Mobile, which in turn is moved by the Unmoved Mover "as a thing beloved."
"That outer sphere encloses and concludes the universe. Beyond it there is only God, who is totally actualized thought, immaterial, enfolding the whole. There is no space out there, for space is "place" and place has ceased. There is no void, because the void does not exist. The universe is an achieved Form, which excludes any reality beyond it. Inside, all is Form again, in a hierarchy of causes which goes down to the individual beings. Plato's concept of Design has been demathematized, Ionian fashion.
"We can see how Aristotle has solved the original problem of the One and the Many. The Ionians had imagined a primeval matter, a single physis, underlying everything. Aristotle shows that it was merely a symbol to be worked out. Matter itself can have only amorphous oneness; it is the raw material, the Possible. Above it there are the efficient causes which ultimately become one cause, the rotation of the Outer Sphere. This is supposed to bring about the motion of the Sun in its yearly cycle, which in turn controls the motions of the four elements. The cause of the change lies in the obliquity of the ecliptic. The formal cause of nature is again, at the summit, one; it is the total Design; and above it is the final cause, which is also the First Cause, God himself. "It is good that there should be only one ruler." Unity is throughout. It works articulated into four levels."
Unquote.
Ali Hijveri's paradox "I am in search of nonexistence" could be a sarcasm in support of the Aristotelian point of view, meaning that the void would cease to exist the moment one reaches it.
Archimedes of 3rd century B.C. commonly recognized as the discoverer of buoyancy stands out as a great forerunner of the later scientists in all fields of mathematical analysis, experimentation and innovation. He not only found a way of testing the purity of gold, but also set in motion the development of hydraulics. It is interesting to note that even in ancient societies, once the process of thinking and exchanging ideas was set in motion, people would appear from nowhere to contribute and develop a more or less comprehensive scenario, even if they themselves did not fully appreciate it.