Lao Tzu, a Chinese philosopher in 4th century B.C. had said, that ‘Life is a series of natural and spontaneous changes.’ And dare we say that he had been correct in every sense of the word?That life is indeed filled with uncertainty, in it’s every nook and cranny. That there’s unpredictability in life’s every twist and turn. In fact, the only certainty in life is that – one day it shall ‘end’.
And while one might argue that the ‘end’ could be a morose thing to talk about. I beg to differ! If the beginning of the universe is such an interesting idea of deep study and speculation. The ‘end’ could be of, just as much interest, if not more!
The universe had originated with a ‘Big Bang’ after all and it might end with an equally big crunch some day.
Yes, you read it correctly, ‘The big crunch’ is one of the most widely accepted theories of universe about, how it will end.
Reversal of the Big Bang – The Big Crunch
The universe that we know today, originated about 13.5 billion years ago from an extremely hot and dense point in space with a giant explosion, called – The Big Bang. Following which, the universe expanded far and beyond our reach and stretched to such an extent, that at present, cosmologist are still unaware of what exists in the 75% of the universe, where the humans haven’t ventured yet. In fact, the universe is still expanding – at a rate far beyond our perception.
Now, according to the, ‘Big Crunch’ theory – if this forever enlarging universe ever reaches a threshold limit of the matter within it, the force of gravity will increase to an extent, that will bring the expansion of the universe to a halt and reverse it in the opposite direction.
In simple words, it would mean that the gravitational force would become so high that different galaxies and stars will start rushing towards each other at a high velocity, leading to a giant collision between them and the subsequent collapse of all universe into a hot giant ball. The size of the universe will then, plummet and plummet even more – until it is compressed into such a small space that even atoms and sub-atomic particles will be crunched together.
The universe will then, once again become an intensely dense, hot and compressed particle in space, just like it has been preceding the, ‘Big Bang’.
The Big Bounce
Another widely discussed theories of universe enlists ‘The Big Bounce theory’. Some cosmologists believe that following every Big Crunch – When everything had collapsed and been reduced to one tiny ball of mass, another Big Bang might follow immediately afterwards. Leading to the universe’s expansion once again. This would mean that the expansion of the universe following a Big Bang and then it’s shrinking back to it’s original point shape by ‘Big Crunch’ is a cyclic process. This is known as ‘The Big Bounce theory’.
Big Freeze: Heat death of the universe
We know that the universe is expanding at an accelerated rate. The galaxies and stars being continuously zooming away from us with time.
But what is causing this never ending expansion?
The answer is – Dark Force.
Dark force is yet another broadly accepted theories of universe and its end. Just like the attractive force of gravity that holds everything together. There is a repulsive dark force in the cosmos that is trying to pull everything apart in the universe, thus explaining it’s continuing expansion. Currently, the repulsive dark force and the attractive force of gravity is in an equilibrium, thereby maintaining a balance in the universe.
But according to the Big freeze theory- millions and millions years later, there might come a day when the ever increasing dark force shall reach to such an extent that it would overcome the gravitational force holding the different galaxies and stars together. In such a condition, the equilibrium between the two opposing forces will end and the universe will be destabilised and the expansion would not accelerate anymore, but the universe will continue to grow forever.
The galaxies and stars will start to separate and zoom away from one another. Even the planets and suns and solar systems within every galaxy will be swept far away from one another, and float as individual objects in the vast space with nothing to hold them together anymore. The light from the stars will be red shifted, with the decrease in energy and the universe will go darker and colder with time, ultimately reaching a frozen state, known as ‘Big freeze’ or ‘Heat death of the universe.’
Big rip:
As the name suggests, this cosmological model states that the universe might end by being torn apart due to the ever increasing dark force in the universe. According to this model the dark force might overcome all other forces around us, tearing apart not only galaxies, stars and solar systems but also the nuclear forces that holds the sub-atomic particles like electrons and protons together in an atom.
Thus, in the case of ‘Big Rip’ not only humongous stars would be torn apart but something as basic as the atoms and sub-atoms will be completely destroyed, leading to the end of the universe.
What it means for us?
While humans are nothing but a tiny speck of dust as compared to the vast scale of this universe, we are also the ONE species which has got the mental ability to reach far beyond our mundane lives and attempt to solve such a complex mystery of cosmos. The above mentioned theories of universe and its end have evidently proved to be more culminating than the origin of the universe was.
And truth be told, even if someday we do find out the exact answer to this great mystery, it will have little to no effect on mankind. Because 6 billion years later when this said end would arrive- we humans will be long gone by then. Forgotten and wiped away from the surface of the earth.
I found the big freeze most intresting.