1995

Poul Anderson's "The Little Monster" was published in 1974 and is set in 1995 by which time there are telecasts from Mars. Since the first Moon landing was in 1969, this was a plausible future.

The young hero's physicist uncle says:

"'Never mind the physics of it...'" (p. 143)

Such an introduction would usually indicate that we are about to read a brief scientific rationale for "...temporal relativistics..." (p. 144) and "'...time projection...'" (ibid.)

All that we get, however, is:

"'Come back when you know tensor calculus, and I'll explain about n-dimensional forces and the warping of world lines.'" (ibid.)

Is that "n" the same as the "N" in "Time Patrol" where a Time Patrol Academy instructor refers to:

"'...the concept of infinite-valued relationships in a continuum of 4N dimensions, where N is the total number of particles in the universe.'"

-Poul Anderson, "Time Patrol" IN Anderson, Time Patrol (Riverdale, NY, 2010), pp. 1-53 AT 2, p. 9.

 

4N is a powerful lot of dimensions but, if there are that many, then there is plenty of room for the mutable timeline, some immutable timelines, the Old Phoenix multiverse and everything else - what I call the megamultiverse.

Lastly, for now (today is Sunday with a walk in the morning and a zoom meeting in the afternoon), there are two kinds of time machine, I suggest: a temporal vehicle carries time travelers whereas a time projector sends them.

In Past Times:

 

"Wildcat" and "The Little Monster" have time projectors;

"The Nest" has a temporal vehicle, the Rover;

"Flight to Forever" has a temporal vehicle called "the time projector."