**Ask a monkey a physics question thread**

[OngBonga]

c tells us the speed of causality... basically how fast we move through time.

g tells us how much a given mass will bend spacetime.

h-bar tells us something too, we just haven't really figured out what.

[MadMojoMonkey]

c tells us the speed of causality... basically how fast we move through time.

g tells us how much a given mass will bend spacetime.

h-bar tells us something too, we just haven't really figured out what.

Why use h-bar and not h?

The difference is only a factor of 2 pi, but which one you choose to use in the calculation of the Planck Length will obviously change the value you calculate.

So which one gives the "real" Planck Length? Why is that the one?