Thanu Padmanabhan, a distinguished professor at the Inter-University Centre for Astronomy and Astrophysics,
NEW DELHI: Thanu Padmanabhan, a distinguished professor at the Inter-University Centre for Astronomy and Astrophysics, Pune, was awarded the Infosys Foundation Prize 2009 for Physical Sciences this week for his contribution to a deeper understanding of Einstein's theory of Gravity in relation to thermodynamics. In an interview with ET, Prof Padmanabhan talks about the behaviour of black holes, the future of our universe and why there might not be any doomsday for the Universe. Excerpts:
Are there other universes apart from the one we live in?
Yes, according to the multi-verse theory, scientists do believe that many universes have been created with the Big Bang. These universes can be likened to bubbles, moving away from each other. It's a theory because no instrument can observe other universes. We will never be affected by them as we will never get in touch with them. They are moving far apart, with speeds more than the speed of light. Our light will also never be able to reach them.
Why does the universe keep on expanding?
The universe systems are trying to achieve equilibrium by expansion. Our universe is also expanding since the time of the Big Bang (which happened about 13.6 billion years ago). It's called cosmic inflation and has been observed scientifically. According to my view, the universe will continue to expand forever till eternity.
So, there may never be a doomsday for the universe?
According to my view, the universe will continue to expand till eternity. And not come back to the same point (self destruction) from where it started.
Will human experiments like the Large Hadron Collider give clue to the existence of universe in near future?
Yes, about 26% of our universe is composed of dark matter — of matter composed of particles other than protons, electrons, neutrons, which we don't know of. In 5-10 years, with such large experiments, we might create such dark matter in our labs. Such matter might behave differently. This might help us in understanding the composition of our universe better.
Why can we never see matter disappearing inside a black hole?
Black holes have immense gravitational pull, from where even light can't escape. So, if a person or thing is falling inside a black hole, human eye through instruments will never be able to see it. It will just appear to approach the event horizon (point of no return on the surface of a black hole), for eternity. That's because of gravitational time dilation, proposed by Albert Einstein in his Theory of Relativity. When a clock is kept on a table and another underneath it, practically both show different times. Gravitational force exerted on both are different. Similarly, very high gravity inside a black hole makes time passes very quickly inside it. The thing may appear to approach the black hole till eternity even as it would have already been absorbed. The difference between the rate of change of time for a black hole to its outside is almost infinite.
Is there a purpose behind the existence of the universe, according to astrophysics theories?
There might not be a purpose behind everything, according to science. Like a pencil standing on its nib falls in a certain direction might not have a purpose. It is just trying to achieve equilibrium. Likewise, if Big Bang and the origin of earth is allowed to happen again, the same protons, neutrons and electrons might combine to form creatures different than what we look like at present.