Hi,

try

m=plank_length*plank_length^plank_length

Motion (m) is very sensitive to the length of the plank, the shorter (and as
a consequence relatively thicker) the planks become the rate of motion can
cease to an almost vegatative level.

Mike



"Marvin P. Winterbottom" wrote:

I need a formula that describes motion without using a time coordinate.
Needs to be consistent with Special Relativity.
(I'm thinking it will involve the Plank Length...?)

Thank you.