The Physics Of The Corridors Of Time

Copied from Poul Anderson And Time Travel:

In The Corridors of Time by Poul Anderson, warring factions called Wardens and Rangers walk or drive along corridors that have been rotated onto the temporal axis. Before entering a corridor, time travellers leaving different periods are separated by temporal intervals. After entering the corridor, they are, theoretically, separated only by spatial distances. Some will be near enough to see each other. Others will pass when moving along the corridor. Therefore, they should encounter and interact with each other and with their later and older selves on their first attempt to use the corridor.
However, such an outcome would complicate the story uncontrollably, especially since the factions are at war. An instant pitched battle inside the corridor would ensure that most individuals did not survive their first attempt to travel along the corridor and therefore never did re-enter it as older versions of themselves. Usually, however, the characters use the corridors without meeting each other. The only explanation given is:
"Duration occurs there too, but on a different plane…" (60)
The twentieth century protagonist, Lockridge, standing in a corridor with a companion, thinks:
"At any moment, someone might enter through some other gate and spy them. (Just what did that mean, here in this time which ran outside of time? He’d think about it later.)" (61)
If he does think about it, he does not do so in the novel. When Lockridge, pursued by Rangers, enters one of the corridors, his pursuers arrive in the corridor not a short distance away from him but a few moments after him. Thus, the order of events in the time "on a different plane" in the corridor follows the order of events in the familiar time outside the corridor. Again, this is convenient for story telling purposes. Lockridge would have been apprehended if his pursuers had arrived simultaneously with him.
If, in Lockridge’s experience, his first journey along a particular corridor starts from the twentieth century and his second journey along the same corridor starts from the fourteenth, which of the journeys will an observer inside the corridor witness first? We must imagine not an observer moving steadily along the corridor from the past towards the future but instead a stationary observer able to perceive the entire length of the corridor simultaneously.
As in the Time Patrol series, Anderson is good at writing his way around potential complications so that the reader is rarely troubled by them. The question in the preceding paragraph occurred to me only when writing about The Corridors of Time. Another potential problem arises when we are told that:
"Emergence cannot be precise, because the human body has a finite width equivalent to a couple of months. That was why we had to hold hands coming through – so we would not be separated by weeks." (60)
The Einsteinian space-time equivalence is not one body width to two months or "thirty-five days per foot" but one hundred and eighty six thousand miles to one second. (62)
Thor Wald, explains:
"Assuming, to keep the figures simple, that Robin lives to be a century old, he would then be roughly a foot thick, two feet wide, five feet five inches in height, and five hundred and eighty-six trillion, five hundred and sixty-nine billion, six hundred million miles in duration." (45)
Thus, Anderson’s corridors that endure for six thousand years would have to extend for six thousand light years in space before they were rotated into time but, in this novel, Anderson avoids mentioning Einsteinian space-time. If space-time equivalence is valid, then the simplest theory is that one of our three space dimensions becomes a corridor’s time dimension. It should be possible to construct a spatial corridor that allows entry to any period of the internal history of one of the corridors. This is another complication that Anderson does not need for the story that he wants to tell so it is not mentioned.