From: utzoo!decvax!cca!knutsen@SRI-UNIX@sri-unix Newsgroups: net.physics Title: Re: Flickering train lights Article-I.D.: sri-unix.3278 Posted: Tue Sep 14 20:33:58 1982 Received: Thu Sep 16 01:16:57 1982 From: Andrew KnutsenThe Michelson-Morley experiment is the oldest "proof" that the speed of light does not change from one frame to another. The problem with the flashing train lights can be visualized using the well-established length-contraction effect. The "track" frame sees the train foreshortened, and the train sees the distance between the lights on the track foreshortened. How can the lights "line up"?