“For a Foggy Night”, by Larry Niven.
The Forest of Time. There was also a sequel short story as I recall.
One day, I hope I transfer to the universe where the “alternate” engine to Big is the real ending. I’d like to see it.
Maybe in one universe it was Niven’s Foggy Night short story, and in another it was Forest of Time
Thank you! I knew it wasn’t “All the Myriad Ways…” but I couldn’t remember the title of the other one.
That sounds familiar – probably is the one I’m looking for.
Definitely not it, but I want to read it. Thanks for the suggestion!
Now to find copies of them. . . .
On the contrary, there was a story I believe called “Infinite Resources” where a man discovers that he can jump to an alternate universe but only by consuming every erg of energy in the one he leaves.
There’s a story about a guy who travels in time by using every bit of energy in the universe - he travels back 18 minutes.
You know, Andy_L, I had never really thought of that. I suppose that if you want to travel 18 minutes, you would need to reverse the entropy of the entire universe by 18 minutes…which is a hell of a lot of entropy to reverse.
Is it a horror story, with him realizing that he and everyone around him only have 18 minutes left before being sucked dry?
This also works in H. Beam Piper’s first “Paratime” story. People who travel from his Prime timeline and return find a “broadening of the bands”, where their original Prime timeline has continued to split while they were away. The longer they’re away, the more alternate timelines they find, and from their point of view it doesn’t really matter which one they choose to call home when they get there.
Of course, this has huge implications that cause a myriad of other problems, so he just kind of dropped it for his later Paratime stories.
It’s from the point of view of a guy who meets the time traveler in the past. “18 minutes” is the punch line.
You can read it here (2 pages)
Oh man, that’s depressing.
But not for the reasons you’d think. You see, I wrote what I thought was an original, clever time travel story. It had a similar denouement. I thought it was…pretty good. Now I see it is just derivative. I’d even read that one linked before! Must have been percolating in my subconscious.
Sorry about it. It happens to the best of us.