ConwayLife.com

Well, there could be a few different metrics. You could just as well use the Manhattan distance (in that case it would be 6c/3 == 2c). It's kind of like how, in 100 ticks, a glider will move from (0, 0) to (25, 25) -- this would make the glider have a "Manhattan speed" of c/2 -- similarly because ...

I am inclined to say that speeds are equal to just the Euclidean distance divided by the period (i.e. (1, 2, 3)c/3 the speed = sqrt(14)/3.)


This would allow speeds faster than c, and would be inconsistent with current usage. The glider, for example, is said to have a speed of c/4, not sqrt(2)c ...