muzik wrote:Could we engineer a spaceship to move at the same speed a human hair grows (assuming CGoL's c is also the real-life speed of light) and still have it run fairly fast in Golly?
Sure, that shouldn't be a problem with current Life technology. At least, we can make something that will run quickly in Golly once the hash tables are populated. It might take a while to get it warmed up, but then Golly could "run away" with it, simulating it pretty much as fast as you want to go, at negligible extra cost.
One likely candidate would be a rebuilt Demonoid or an Orthogonoid, with a speed that's a negative power of two -- let's say (2^-56)c, since that's more or less the rate of hair growth as a fraction of the speed of light. It's better if the step size is also a power of two.
Any factor other than 2^N in the step size or period will multiply the number of hashtiles needed by that factor. At a period around 2^56, you're bound to run out of memory and have to start garbage-collecting -- unless the period is exactly
2^56, in which case Golly knows the entire future history of the pattern as soon as it has calculated one cycle.
We can't get to (2^-56)c by adjusting an existing Demonoid, because the replicator units' 180-degree reflector doesn't have the right phasing mod 8. So a complete rebuild would be needed there, including new self-destruct circuitry.
However, the most recently posted Orthogonoid design
could be set up to run at human-hair-growth speed, simply by moving the replicator units far enough apart.
Somebody just has to add the MWSSes to program the existing circuitry to construct a copy of itself and its construction elbow at (0,-256), and shoot down the copy behind it. Once that's done, it's all set to travel at any speed you want!