Thoughts about the greatest mystery ever – the arrow of time. Only in retrospect can you decide, whether reading this article was worth the effort. And let us face it – There is no future. There is no past.

A major chunk of all the decisions we take in our lives are optimization problems But a situation commonly arises where the cost of setting up and solving an optimization problem exceeds the effects of the solution itself – a situation referred to as “analysis paralysis“. Only in retrospect can we look back and see if a problem could get solved. It is never possible to know in advance if it is worthwhile trying to solve it.

Similar is the case while coming up with laws of physics. Just as you can never be sure if all swans are white, you can never be sure if the current physical law is 100% correct. Only in retrospect, when you’ve discovered a better law can you look back in time and see how the earlier one was merely an approximation and how the new law is a better approximation of reality. It is impossible to say if all swans are white. And it is impossible to say if we will ever find an exact approximation for reality.

Only in retrospect can we see whether a Turing machine stops while going through a complex algorithm. Only when we have the concept of the time domain in place can we see the clear difference between P and NP problems.

Kind of makes me wonder, what if the arrow of time suddenly reversed? 

If the universe pressed the rewind button right now, will I have to do what I just did, backwards in time? So will I be forced to “unwrite” this article? Do I only get free will while moving forwards in time? The universe works in mystifying ways and amazingly, only in retrospect will we be able to find out whether free will actually exists backwards in time.

Only in retrospect can we see the past. The arrow of time moves as entropy flows into the universal bucket, awaiting an overflow. Delusional are those who think the nature of occurrence in our world is cyclic. History rarely repeats itself. And only in retrospect have we realized this.

Even chance is a slave of time. If the amount of data or knowledge we have is not dependent on time, all outcomes are deterministic. What use is coin toss experiment then if everything is already known across the time-domain? It is only because of time that we can slowly assemble the greater puzzle of knowledge as the curtain of experience unfolds revealing new jigsaw pieces.

And let us face it. There is no future. There is no past.
There are speculations and dreams which allow our imaginations to wander across a future land. There are memories which give us this false sensation of there being a meaningful past.

If there were no thoughts, would there be a future?
If there were no memories, would there be a past?
If there were no humans, would there be time ?

In retrospect, someday, I would be glad to know the answers.