Have you ever spared a thought to this, seemingly "trivial" question? It is not as simple as it looks. Time, as we perceive it, is clock-ticks, hours, minutes, days, years, centuries and ages. But, is this really time that is passing?
Well, you guessed it right, it depends on how we define time. If time is defined as "something measured by a clock" then the above hypothesis might be true and you don't need to read all the prolix prattle which follows. But, if we consider time as something which gradually passes, then we have a problem.
Consider an Arrow. its motion is similar to passing of time. Now, according to Heisenberg's Uncertainity principle position and momentum of this arrow cannot be accurately and simultaneously determined (Yes, it is true even for macroscopic bodies!!). And it is true, if we photograph the Arrow, we know its position, but we have lost all the information about its momentum. and if we see an arrow moving, we know its momentum (as a vector), but we can't determine its position !!
Now, its analogy with time. If time is an Arrow. and say the arrow is moving, then we can't say whether we are in Past, Present or Future !!(its position can't be determined). and if we assume that we are in the Present. then Time is stationary (momentum cannot be determined !!). Thus, a fallacy!!
The thing is, we confuse time with relationships. We measure time (lets call it that for the time being:) ) with respect to some cyclic changes like Earth's revolution around the sun or moon's revolution around the earth. Which implies, that if these motions slow down, time will slow down !! ... therin lies the fallacy! .. we don't measure time, we compare ourselves with other activities. This comparison should not be confused with time!
So, there is nothing called time.
Time is just a perception. An imagination of human mind. That explains why time (the colloquial "time", acutally there is nothing like time) seems to pass slowly while we do a boring piece of work and why time seems to fly away when the work we are doing is interesting! Because, clock-ticks is not time, neither is the location of sun or moon with respect to the earth!
Then what is past? what is future?
Past is just an improbable event. i.e. the waves of probability have grew stronger for the Present and weaker for the past. Also, the waves of probabilty are weak for the future. So, future is also an improbable event, as of now.
To understand it completely, well, consider a gramophone record. Assume, the needle is at a particular point playing your favorite song. Well, it just implies that the other parts of the record are improbable and the part which is being played in highly probable (the analogy with past, present and future in simple).
To summarize the above paragraph, well, past and future are nothing but, improbable events. There is nothing called "time" as such !!
Its all quantum mechanics. As true for macroscopic objects as for microscopic!
So, go over the topic again ... What is time? .. does it seem that simple yet??:))
12 hours ago