________________
A CRITIQUE
-
131
of negatively charged particles (electrons) rotating - round the central nucleus which itself is composed of a number of positively charged particles (protons) and electrically neutral particles (ncutrons) Protons and neutrons are much heavier than electrons so that the nucleus contain 99 97% of the total atomic mass The number of protons, neutrons, electrons are different in different elements but the atom on the whole is electrically neutral because the total charge of all negatively charged particles equals the total positive charge The simplest and lightest atom is That of hydrogen It is composed of a single proton as the nucleus and a single electron orbitting round it Its diameter is 10 -8 centimeter and mass 1 64 x 10 ?? grammes The distance between the nucleus and the rotating electron is such that the atomic diameter is 100,000 times greater than the diameter of the nucleus In the atom of Uranium there are as many as 92 protons and 146 neutrons in the nucleus and 92 electrons rotate round it in different orbits
PARAMAŅU INDIVISIBLE UNIT OF MATTER i Paramāņu, as defined by Jain philosophy, on the other hand is a truly indivisible fundamental unit of matter and therefore has no components It is not composed of many particles and is dimensionless Like a true geometrical point, it has no length, no breadth, and no thickness Its centre is identical with its ends Thus it has no extension and occupies only a single space point It has no shape and it has no mass It is, however, not an abstract piece of matter deprived of the qualities of colour, smell etc, like the atom of Democritus It has a real objective existence and does possess colour, smell, etc Inspite of this, a paramānu by itself is not perceivable by sense organs
