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COSMOLOGY : OLD AND NEW would be all chaos, there would be no world. The atoms 76 would be scattered throughout space; the galaxies would disperse; the members of the solar system would be torn off one from the other. Hence the necessity of the important postulate of adharma dravya, the gravitation.
It should be borne in mind that Newton regarded the force of gravity as an active force, although acting like an invisible agency. The modification of the concept of gravitation introduced by the author of Relativity, Prof. Albert Einstein, renders gravitation quite inactive and thus brings it on the same level as the adharma dravya of the Jaina philosophers.
The view of Einstein can be approached in the following manner : Suppose this room is a lift"; the support breaks and down we go with ever-increasing velocity, falling freely like a stone. Suppose I am inside the lift and I perform the experiment of dropping an apple held in my hand. Remember that the lift and all things contained in it are falling freely all the while. To my surprise I shall see that the apple cannot fall any more than it is already doing owing to the free fall of the lift. The apple remains poised in my hand. The force which causes apples to fall, i.e. gravitation as an active ageni, disappears, so far as the man in the lift is concerned.
How ignorant science is of the ultimate nature of gravitation is prettily set forth in a story told by Einstein, as a preliminary to a popular exposition. “Suppose”, he says, "that a man were put into a perfectly dark cage that was poised, motionless, far out into inter-stellar space. The man would not weigh anything, he could move from one side of the cage to the other,
from top to bottom, by the slightest push: he could float in the middle of the cage without touching it. Suppose that, unknown to him, a cable were attached to the top of the cage and
76. We have pointed out that the earth moves round the sun because of gravitational attraction. In the case of atoms, however, gravitational attraction plays no real part. The masses of electrons and protons are too small for that. On the other hand, here there is an incomparably greater electric force, i.e., the force of attraction between the positive electric charge of the proton and negative electric charge of the electron. (see Footnote on p. xxiv of Prologue.) However the law which governs this attraction is exactly similar in form to the law of gravitation, so that it is merely a change of name. It is again in force of attraction which keeps an electron moving round the proton.
77. Lifts, electric or hydraulic, are fitted in various buildings, railway platforms, etc., for going from one storey to the other.