I remember an episode, I think it was from The Twilight Zone or The Outer Limits.
A scientist finds a rock.
There is a world simulation happening on that rock, wherein grows a small simulation of our own evolution (by chance?)
The rock is then put in a room, inside a glass.
The scientist monitoring the rock world's evolution follows it with great interest as a comparative history method of our own evolution, and in hopes of predicting our own future, as they are evolving very quickly in a way very similar to the Earth´s history.
By the time it reaches the equivalent of our time and they master atomic energy, there appears a shadow around the rock.
The shadow turns out to be a ghost that does not let the observer follow the experiment or even get near the rock anymore.
Any idea of what episode is this?