Stephen William Hawking (1942-2018) was an English theoretical physicist, cosmologist and the Lucasian Professor of Mathematics at Cambridge. He authored ‘The universe in a nutshell (2001) and ‘A brief history of Time’(2005). When he was doing his graduation at Cambridge, he was diagnosed with the motor neurone disease that gradually, paralyzed him with in a decade. After the loss of speech, he communicated through a speech generating device, in the beginning through the use of a handheld switch and at the end by using a single cheek muscle. Hawking was the first to set out a theory of cosmology explained by a union of the general theory of relativity and quantum mechanics.
‘Questioning to Universe’ is a TED talk of Stephen Hawking where he answers the questions that need answers from an authentic persons like him.
How did the universe come into being?
Where did we come from?
Are we alone in the universe? Is there alien life out there?
What is the future of the human race?
His answers are based on his scientific insights and theoretical framework.
Until 1920s everyone thought the universe was essentially unchanging in time. Then we came to find that the universe was expanding. The distant galaxies that were closed to us billions of years ago, moved away from us. Actually, this was the big-bang, the beginning of the universe. The universe expanded from the initial state of high density and temperature before 13.77 billion years. As the General Relativity and quantum theory allow time to behave like another dimension of space, under extreme conditions, the distinction between time and space removed. So, the law of evolution can also determine the initial state. Thus, the universe has spontaneously created itself out of nothing.
Then Hawking talks about the two pieces of observational evidence on the probability of life appearing. The first is that we have fossils of algae from 3.5 billion years ago. Life appeared on earth, that was formed 4.6 billion years ago, only after only after a billion years. As it didn’t happen earlier, the probability of life appearing is reasonably high. Here, Hawking emphasizes the crucial role of self-replication and 'primordial soup' in the emergence of life,that helps to believe life might have emerged from a mixture of organic molecules in the earth's oceans as they can reproduce themselves. As we believe that life arose spontaneously on the earth, no doubt, there are possibilities for life to appear on other sinkable planets in the neighbouring galaxies. But, as we haven’t been visited by any aliens so far and as we haven’t heard any radio waves from them, Hawking believes that we are the only civilization within several hundred light years.
Hawking is also of the opinion that as our population is growing and as we change the environment with the technical ability, it will be difficult to avoid disaster in the next 100 years. So, our only chance of long term survival is not to remain on the planet Earth but to spread out into space. Thus through his TED talk on 'Questioning The Universe', Hawking, not only gives answers to a few questions, but highlights the intriguing possibilities and need for ongoing scientific investigations in the future.
-----Thulasidharan V
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