For those who may be confused with stating that time doesn't exist: Time as in a physical parameter may not have any actual existence unlike mass or charge. However the concept of time does exist. We perceive it through the change that happens within us and around us. The change is largely unidirectional, meaning that we cannot undo what happens. This is the sense of entropy - the idea of order reducing and disorderliness increasing in everything in this universe.

Entropy has a tangible form. We can observe it and measure it. We grow from a zygote into a full blown adult, who has cells being created and destroyed all the time in randomly different parts of their body. There is no unique pattern in this.

Mountains crumble even if a tiny bit in many years; stars shine out their light; galaxies move apart on large scales. Even the human mind which desperately tries to fight to secure order in the "world" of that person, cannot but digress and diffuse eventually.

Time is the perception of entropy and not a physical quantity in its own right.

But then, should we even measure it? Well ... That's for another time.