In the course of reading The Fabric of the Cosmos by Brian Greene, I came across an intriguing concept, that travel to the past may perhaps be possible, but that changing the past is not. The reason for this is, more or less, that each moment is its own immutable now. Sound familiar, fans of Walt Whitman and St. Augustine? I wrote a paper in grad school dealing with the eternal nature of now in relation to the Tree of Charity in The Vision of Piers Ploughman. It's a subject that interests me.
In particular just now, however, I found Greene's idea provocative because one of my current active projects deals specifically with time travel to the past that goes awry. The traveler ends up in a couple of different parallel realities rather than going straight back in her own. One of them is pretty far removed from her own timeline, and I've been wondering how such a major mistake could have happened. Her friend, the “time machine’s” inventor is a talented and highly skilled quantum mechanician. How did he land her so far from her home reality?
Since reading Greene's remarks, though, it occurred to me to wonder if it really was a mistake as such at all. Maybe the operator of the "time machine" meant to send the traveler to a parallel reality all along. The story is told in first person narrative by the traveler, a person who knows next to nothing about Quantum Physics. The operator could have told her a fib, an oversimplification...His goal might have been to send her to a parallel reality all along, since he knew that changing the past, as such, is impossible.
I'll need to chew on the idea some more, but it presents possibilities. It may mean that the story is more complicated, and thus more interesting, than I initially anticipated. That's good, since simple stories don't sell.