First page Back Continue Last page Overview Graphics
Answer: Leapfrog is time reversible.
Suppose we step back from (ti+1,xi+1,vi+3/2) to (ti,xi,vi+1/2). Applying the algorithm:
- vi+1/2 = vi+3/2 + f(xi+1)(-t)
- xi = xi+1 + vi+1/2(-t)
- These are precisely the steps (in reverse) that we took to advance the system in the first place!
- Hence if we Leapfrog forward in time, then reverse to t = 0, we're back to where we started, precisely.