Microcosmology: Atom In Jain Philosophy & Modern Science: [1.3.5] Atom in Modern Science - New Physics - Subatomic Level - the Heart of the Atom

Let us now descend to the subatomic level for a more detailed study of the nucleus - the heart of every atom. It is not necessary to know more about the nucleus than its charge and its mass to understand the great variety of molecular structures. But to unravel the nature of matter, i.e. to comprehend what matter is ultimately made of, the study of nucleus is essential because it contains almost the entire mass of the atom. Whereas the structure of the outer body of the atom can be, to a certain extent, compared to a miniature solar system, the structure of the nucleus itself presents an entirely different picture. The main task of the post-quantum theory physicists was to study the structure, i.e. the constituents of the nucleus as well as the forces, which bind them together as a stable entity.

First of all, it is clear that the nuclear forces which tightly bind the nucleus together cannot be of the familiar electro­magnetic origin, since the protons are all positively charged, thus repelling each other. (The electromagnetic repulsion force in the nucleus varies inversely as the square of the distance separating the positively charged particles. Prof. E. Soddy has figured out that two grams of protons placed at the opposite poles of the earth would repel each other with a force of twenty-six tons.)

It must, therefore, be an entirely new force of nature, not encountered anywhere outside the nucleus and must be many times stronger than the repelling electromagnetic force. In fact, it is one hundred times stronger than the electromagnetic force and is the strongest force known in nature. (This strong force can be compared to that encountered in ordinary liquids causing the phenomenon of surface tension. In the atomic nuclei, we have similar force of much greater magnitudes acting as the cosmic cement which prevents the breaking up of the nucleus under the action of electric repul­sion between the protons. Thus, if we assume the nuclei of different ele­ments to be droplets of a universal "nuclear fluid", the density of such a fluid will be 24 x 10 times that of the water. Its surface tension forces will be about 1018 times larger than those of water.)

We have already seen that the nucleus is about one hundred thousand times smaller than the atom itself but it contains almost all of the atom's mass. A nucleon has the same quantum nature as an electron and, therefore, reacts, to its being squeezed into a much smaller space, more violently than electron. It races about in the nucleus with an incredible velocity of about 40.000 to 50.000 miles per second. We have already seen that the nuclear matter is extremely dense (If a mass of about 100 kg. were to be compressed to nuclear density, it would take less space than an ordinary pin-head) compared to matter at macro-level. The high velocity and high density of the nuclear matter is, thus, entirely different from any thing experienced at the macro-level.

The exclusively unique aspect of the strong nuclear force that makes the nucleus an extremely stable unit is that it acts as an attractive force when the constituent nucleons are at a distance of two to three times their diameter. The very same force is strongly repulsive when the distance becomes less so that the constituents cannot get any closer. Thus the equilibrium is dynamic and yet extremely stable.

The comparative instability of the radioactive elements is explained thus. The electromagnetic force of repulsion between the positively charged protons tries to disrupt the nucleus into its constituents. This force is countered by the strong nuclear force which tends to keep it unified. Now if the repulsive force predominates, the nucleus will have a tendency to break up into two or more parts, the process being known as 'fission'. On the contrary, if the strong nuclear force holds the upper hand, not only he nucleus will never break by itself, but will also have a tendency to fuse with other nuclei coming into its contact. It is now established that the electric repulsion forces prevail in all heavier nuclei, while the cohesive forces hold the upper hand in the lighter elements from hydrogen approximately up to silver in atomic table (See Appendix Atomic Table). Each proton or neutron in the elements weighs less than it does in the free state, the loss of weight equal to the energy binding the nucleons. This loss becoming progressively greater for the elements in the first half of the atomic table, reaching its maximum in the nucleus of silver. After that the loss gets progressively smaller. Since each loss of mass manifests itself by the release of energy, it can be seen that to obtain energy from the atoms, nucleus requires either the fusion of two elements in the first half of the table or the fission of an element in the second half.

[1] Please see Chapter III for discussion on this point.

However, because ofthe state of metastability, neither the fission nor fusion would occur normally unless something was done to start the process [1]. And the process of starting a nuclear reaction is extremely difficult because it needs very high activation energies.

The available energies, when the temperature is not too high, are not high enough, to disturb the nuclear equilibrium, and as we have stated earlier, mostly electrons are responsible for the diverse nature of physical existence on earth.

The multitudes of shapes and molecular architecture can exist only on earth where temperature is not too high.

In the stars, where the thermal energy increases a hundredfold and where most of the matter in universe exists, the state of the matter is radically different from that on earth.

[2] Further description of solar processes is given at the end of this chapter.

In the center of stars, where temperatures are very high, the matter exists in large accumulations of nuclear matter and nuclear processes, which are rare on earth, predominate there. Of particular importance to us are nuclear reactions in the sun because they supply life-supporting energy on earth. The discovery that the constant energy-flow from the sun is the result of nuclear reactions is one of the significant achievements of modern science. [2]