The “Great Silence” is the observation and contradictory nature of why we have not found life elsewhere in the cosmos. The sheer size and age of the universe suggests that there should be something out there which is more advanced than us or at least on a par, so why has no evidence been found yet? The Milky Way alone is so old that enough time should have passed for an alien civilisation to have conquered it hundreds of times over.
Yet, as far as scientists are aware, we are the only inhabitants.
This leads to the Fermi Paradox.
In 1950, physicist Enrico Fermi – the creator of the world’s first nuclear reactor – came up with a paradox which says due to the age and size of the universe there is bound to be a civilisation much more advanced than ours, which begs the question: “Why is it just us?”
The solution, many scientists argue, is once a civilisation reaches a certain size, it eventually kills itself off, either through war with advanced weapons or natural disaster.
Now, one expert is arguing that if we are truly alone, as seems to be the case considering little evidence has been discovered so far, then it does not bode well for humanity.
Bryan Walsh, author of the new book End Times which analyses the existential threats which humanity faces, believes “we should be worried” if we are alone.
Mr Walsh said in the book: “If we are truly as alone as we now appear, then perhaps intelligent life is an unlikely accident of cosmic fate, one in a 100 billion – the number of stars in the Milky Way.
“If so, our fate is even weightier, for Homo sapiens would become the cosmos’s sole conscious observers.
“Or worse, perhaps intelligent life has arisen elsewhere in the galaxy, only we see no evidence because aliens have been destroyed over and over, or have destroyed themselves.
“Maybe every time the experiment of intelligence has been conducted, it has failed.
“If that is the case – if the apparent lack of intelligent life in the galaxy is the product of repeated cosmic catastrophes that destroyed alien civilisations, as we ourselves are in danger of being destroyed – then are we too doomed to extinction?
“We should be worried.”
There are several threats in End Times which Mr Walsh believes has the potential to wipe out humanity.
These include asteroids, disease, nuclear war, bioterrorism, volcanoes, climate change and artificial intelligence.