Forum author Mr. K. has implemented a script into a cube that allows the simultaneous run of a physics simulation and scene transition.
Here is a test video example: http://www.youtube.com/watch?v=-FefrAAGfpU
With proper adjustment of the scenes and the transition rate in the script, the simulation can run very smart.
Link to the post with the scripted cube: http://sketchucation.com/forums/viewtopic.php?f=61%26amp;t=36109%26amp;p=345444%26amp;hilit=scene+in+physics#p318368