On Jan 23, 2006, at 9:19 AM, Merlyn wrote:
Having loads of fun here <my email truncated the interesting and relevant parts of the previuos messages, so no quote possible> Horace, your gedanken experiment involving the dropped rock neglects the fact that light carries momentum. In order for the rock to be turned into light ttraveling the opposite direction, a force must be applied to reverse its momentum. Equally, Einstein at the top of the ladder must apply a force when he catches the light to stop it and turn it into a stationary rock.
That was not my gedanken. It was Keith's. Horace Heffner
