Question no 1: Sir, I have read about Big Bang theory. I wish to know more about it. Will you please tell me something about essential features of the theory?
Answer: Yes, I shall give you a brief introduction of Big Bang Theory. The Big Bang theory is the most commonly accepted model for the origin of the Universe since it is an experimentally derived theory. The underlying principle behind the Big Bang is that, the Universe was in a compressed state 4 to 5 million years ago. After the Big Bang, the Universe started expanding which is continuing yet. The experimental proof for this is available from the outer space. Distribution of galaxies extends uniformly in all directions and because of gravitation they move with respect to each other. They move away from the Milky Way with speeds that increase with distance which is a standing evidence for the Big Bang. trường đại học việt nam
Q 2: Sir, what happened after the Big Bang?
Answer: Though this theory is accepted by and large as the only theory which explains the origin of the Universe, the theory itself postulates or in fact, provides for a ‘hot, dense matter’ during the Big Bang. It further assumes Gravitational effects which are of high magnitudes. As per the theory, the entire fate of the Universe was decided in five minutes after Big bang and after that, nothing substantial took place.
Q 3: In such a case, can I say that Big bang supposes existence of matter even before Big Bang?
Answer: Definitely yes. Also we should consider what is the source and what is the cause for such an enormous action. According to law of conservation, from nothing, ‘something’ could not have come. In other words, if it could have come from nothing, laws of conservation fail. Hindu Religion states that there is an Almighty, Who is the ultimate commander from ‘Zero’. I am not wrong if I say that there is some hesitation on the part of the scientific community itself to accept Big Bang theory because it postulates such pre-existence of the Universe,
Such pre-existence of matter is taken as the first postulate for our consideration of The Double Universe theory.
Q 4: Sir, it seems there are some other models for the formation of the Universe. I have read about Steady State Model or ‘The Cosmological Principle’. Please tell me something about it Sir.
Answer: There is one weakly accepted alternative theory to Big Bang which was supported by none other than Albert Einstein applying his General theory of Relativity known as ‘ Steady State Model’ or ‘The Cosmological Principle’
“The Cosmological Principle” or the steady state model proclaims that the Universe ‘always exists’ as it is and there is no change in the overall situation especially with respect to the observer from any point in the Universe. Because of the changing positions of the Universe, this theory has gained momentum, as observed by the red-shifts. While the Cosmological Principle is able to explain the present state of the Universe, it is unable to explain the cause of the Universe. To explain the origin, the Big Bang model is used.
‘The Universe always exists’ is a very useful postulate to propound Double Universe Theory and it is the second postulate.
Q no 5: There is one more theory known as ‘The Oscillating Universe’. May I know about it Sir?
Answer: To explain the situation ‘before’ the Big Bang, a concept of “Oscillating Universe” was put forward by the Russian Astronomer Ernst J. Opik (1893-1985). He says that after, say 25,000 million years, the expanding Universe will stop expansion and start shrinking as a stone thrown upwards, having exhausted all its energy comes back to the ground, due to gravity.
If we assume the age of the Universe as 4,500 million years it means that the Universe exploded 4,500 million years ago. The energy for this explosion must have come from within the matter itself known as the nuclear fluid.
German Priest and Astronomer George Lemaitre (1894-1985) was the first to visualize such an initial state of the Universe. He pointed out that at the density of the nuclear fluid, this state would correspond to a “GIANT ATOM” or a primeval atom or Egg, from which the Universe hatched. This “egg” must have been very much unstable as the radioactive unstable atoms: It must have decayed simultaneously exploding at the instance it was formed. Our present Universe would thus consist of the debris of radioactive decay of one huge, single atom.
How did this primeval atom come into being? On one hand it should have been created. Creation is beyond the scope of Science. The alternative is an assumption of a previous state, “a collapsing” Universe which converged to a single spot from all directions. The collapse was stopped at the maximum possible density of matter, whose elastic forces sent the Universe back expanding like a ball rebounding from the wall. Thus the theory of Opik presumes a “Cosmic pendulum”(Oscillating Universe)