A simulation illustrating the "twin paradox" of the Special Theory of Relativity.


Twin A is the "home twin" while twin B is the "travelling twin".
A and B are initially co-located, could be on the Earth for all I know.

B is accelerating away from A, and is returning when he is ten light years away from A.


Scrollbar "Acceleration distance":
Choose how long B accelerates. 0.1 - 5.0 light years in A's rest frame.

Scrollbar "Acceleration":
        Choose B's proper acceleration. 0.01 - 2.00 c per year.
        (1 c per year is about the same as one g.)

Choice box:
     Choose from whose frame of reference to see the journey. "A-view" or "B-view".

Button "Start":

        Run the scenario as viewed in the chosen twin's frame of reference.

Button "Pause":

        Pause the run.

Button "Resume":

        Resume a paused run.

Button "Reset":

        Reset the run.


You can run the simulation either as an Applet or as an Application, se how here

Run as Applet

Download Application


Best regards Paul B. Andersen