[lostmsu]

So they still can exist. I don't think they meant that any such configuration would run, just one.

[4ad]

The empty board is a repeating pattern of length one.

[lostmsu]

The question was related to the simulation of game of life linked by the OP. E.g. Can a full simulation of game of life simulate itself.

[svara]

Yes but the question is whether there are repeating non empty patterns. I don't think you've answered this? I don't know but I think that's a fascinating question.