What's the smallest measurement of time?

IE: nanosecond.

I guess it would be what is used in quantum mechanics which is the Planck. It is a measurement of distance but also of time. It's about 1.6 x 10^-35 meters or 10^-43 seconds. It's the amount of time that a proton (traveling at the speed of light) takes to travel a distance of 1.6 x 10^-35 meters.

And that time would be even smaller if it travelled only, say, 1.6 x 10^-70 metres.

Why would someone work out something like that? What importance does it have other than to say "Ha! I own you at Maths"?

welp.....

re-welped...

I wonder where the hell they got the 5.4 from...

And then I wonder why I asked this question anyway. I can't remember the reason.

re-welped...

This is the same thing I posted. What the?

years – scale of an estimated Poincaré recurrence time for the quantum state of a hypothetical box containing a black hole with the estimated mass of our entire universe.

Someone please explain.

Also, I believe a Yoctosecond is the smallest named measure of time.