whats the significance of the Planck length? and can it be disproved?

The Planck Length is the shortest MEANINGFUL distance. Quantum mechanics tells us that it is impossible to measure a shorter distance. If for no other reason, the universe is so chaotic at that scale that a measurement cannot be taken The question then is, "if we cannot measure something smaller, does it exist." (The smallest conjectured object is a :String from M-Theory. A String is a Planck Length. There is no physical entity smaller. If there is nothing smaller, what is the use of a unit of measure smaller?)

http://en.wikipedia.org/wiki/Measurement_in_quantu...

A nice philosophical question to explore. Have fun.

The plancks length is actually the smallest length that exists because you cant measure something smaller. 1,6*10^-35 metres is way to small to measure with our current technologies so there are no hopes of proving or disproving it by experiment in the coming future.