But it was still something not something that could be measured or proved as fixed. Newton in his Princpica observed God as he is everywhere he would be keeping time same through space. And no one I guess even thought about it since it something contrary was not in our everyday experience.
And here came Einstein and in his special theory of relativity told that time is no longer fixed and only thing fixed is speed of light !
He devised a simple thought experiment , simplicity of which has amazed me too.
Suppose we are in a train platform and we observe two strikes of lightning happening at same time in front. Now imagine there is a person on a train , and train is speedimg towards lightning which is to come on right. As train is speedimg towards lightning which is to come on right, he will observe lightning on right happening first than that on left.
So to observer on train two lightning strikes are not simultaneous events, his perception of time will be different than person on platform.
In short there is no absolute time or absolute tick tock happening throughout universe.. Time is a relative function of movement of refernce system.
In Hinduism we hear stories of time travel including one story of a king going to God Brhama (in a diffrrent universe), and after a while God Brahma tells him that in this short time , millions of years have already occurred on Earth. Are these ancient texts trying to tell us high technology from our past in form of a story (easier to pass on to next generations )?
Is it possible that during all these million years of Homosapiens, serious technology was only developed in last 1000 years ? Is it practically possible ?
Isn't it like mathematical improbablity of there being no aliens , will all billions of stars and galaxies in universe ?
The more we know I guess we will come to the realisation that we don't know.
