So far, we have discussed the development of those parts of the science of Physics which relate to the understanding of the universe around us. Theorization from a mass of data collected from observation and experimentation, or theoretical analysis resulting in the prediction of what would be discovered later, are the two main modes by which Science grows. However, there is no dearth of anomalies in Science, some of which have been occasionally highlighted in the preceding text.
One of the topics which has not been discussed at any considerable length in spite of being significant to the aims and objects of this work is Cosmology which combines astronomy with the more recently developed techniques of radiotelescopy and spectroscopy. With these techniques, it is now established that the Sun, like other stars, is a dense mass of plasma with a core temperature of about thirteen million degrees Centigrade consisting mainly of hydrogen and small amounts of heavier elements formed by nuclear fusion which constantly releases heat energy producing the blinding illumination. It is also believed that planets have formed due to the separation of small quantities of spinning gaseous clouds containing heavier elements which gradually cooled and condensed into bodies such as the Earth.
However, it is curious that while ninety two elements and hundreds of isotopes are formed in the complex process of nuclear fusion, transmutation and, probably fission in stars, the dozen elements of the man-made trans-Uranic series are not formed naturally.
Even more curious is the fact that the steady state theory of the formation of the universe assumes that stars were formed by the gravitational collapse of very large clouds of hydrogen gas which created such high temperatures and pressures that nuclear fusion reactions took place in them without any external detonation. But regular hydrogen found abundantly in the water of our oceans and whose nucleus has only one proton does not take part in nuclear fusion no matter what you do with it. Only isotopes of hydrogen such as deuterium whose nucleus has both a proton and neutron and tritium whose nucleus has one proton and two neutrons take part in nuclear fusion. So it seems that the original gas clouds would have had predominantly deuterium and tritium and so would be the case with our Sun. And since our Earth is believed to have originated from the Sun, the waters in our oceans should have been mostly heavy water in the beginning which may have transformed into normal or light water over billions of years. But then the same would have happened in the stars including our Sun and the fuel for the fusion reactions should have ended ages ago.
The advances in the techniques of radio transmission and reception during the first half of the twentieth century, and the invention of radar and eventually radio telescopes resulted, during the 1960's, in the discovery of some unique phenomena called Quasars, Pulsars and Black Holes. The quasars are very large stars, though much smaller than galaxies, at great distances beyond the limits of our own galaxy (The Milky Way which is known to be so large that light takes a hundred thousand years to travel across it; and containing roughly a hundred thousand million stars) which are not only visible with optical telescopes but also emit radio waves and ultraviolet radiation. Scientists are unable to explain how such relatively small objects can generate such inconceivably large amounts of energy that they appear bright at such huge distances. Pulsars are celestial bodies, again at very great distances, but estimated to have planet (Earth) size dimensions characterized by the emission of regular pulses of radio waves every second or fraction thereof.
Our knowledge about the Earth, the Solar system and the Universe as a whole has been considerably augmented by the data obtained from satellites equipped with sophisticated electronic gadgetry sent into outer space, earth orbit and orbit around the Sun with the help of powerful rockets developed initially for military purposes. The paths of these satellites have, however, remained within the range of the orbital planes of the planets of our Solar system.
To explain the complex cosmological phenomena, a new science of astrophysics has come into existence which correlates the known facts of other disciplines particularly physics with astronomical observations. For instance, several mathematical models of the universe's evolution and lives of stars have been based on Einstein's general relativity. The equations represent such fundamental canons of physics as preservation of the sum total of mass and energy in the universe, the conservation of momentum, the balance of forces etc., and are solved starting with the initial condition that all matter and energy was concentrated at a point in a boundless vacuum where it suddenly exploded, expanded and eventually diluted into what we see as the universe around us, which is still believed to be expanding.
Thus although the void of the universe is assumed to be infinite, the expanded material part must always have a dynamic boundary within which all our observations are limited, enveloped by a larger expanding sphere of radiation energy which must have escaped in all directions at the speed of light; a sort of universe within universe within universe, the radius of the radiation envelop being about twenty thousand million light years if the current estimate of the age of the universe is correct.
As for what came out of the big bang initially, it is obvious that the vital fundamental particles were formed which then combined in their own ways to form subatomic particles and so on.
Oddly enough, all the estimated matter and energy in the universe fails to account for all the gravitational forces that are supposed to be acting in it; and hence the existence of large quantities of some sort of speculative dark matter beyond perception is suspected, perhaps similar to the apparitions of some religious beliefs. However, there is a spectrum of solutions to the equations of general relativity that range from a continuous and indefinite expansion at the present rate to an eventual slowing and subsequent contraction to a dense state. Identical analyses can be carried out for either the entire universe or a single star or galactic system. The pulsars, thought to be the remnants of such collapsed stars are also called neutron stars and are believed to consist largely of tightly packed neutrons with a density that is a few billion times that of earth such that a cubic centimeter of their matter would weigh a few million tons on earth.
Many astrophysicists believe on theoretical grounds that the gravitational collapse of a star could create a high density object whose gravitational field would be too strong to allow anything -- including light waves -- ever to leave the body. Such hypothetical objects are called "black holes", because light and other signals being unable to emerge from them, their matter has literally disappeared from view, although they continue to influence the motion of other stars in their vicinity. Based on irregularities in star movements and the emission of very short wavelength radiation, a number of black-hole locations have been conjectured by astrophysicists. What is more interesting is that scientists believe that the normal laws of physics would not be applicable in the vicinity of black holes which are said to be capable of "devouring" any matter that approaches them and loses its physical structure.
We thus find that an extension of our knowledge of Physics and Astronomy brings us to a point where we must start looking for a new set of physical laws which could naturally bifurcate into two sets of physical laws, one governing the events in our galaxy, and the other in the vicinity of the black holes. For those who believe that the laws of physics are universal and everlasting, this must be a minor shock. On the lighter side, blackholism seems to have existed among people for some considerable time in the form of persons who are always ready to grab but never willing to give away anything, and somehow they seem impervious to all norms and laws.
