Variability And Solidity

My point recently has been that Poul Anderson's Time Patrol series has two almost contradictory aspects:

subtle, counter-intuitive reasoning about variable reality in "abstract space-time";

concrete historical details like the up-to-date Empire furniture in Berlin in 1858, heavy-looking oak furniture and thick carpet in London in 1894 and "...a solidity that had endured and accumulated since the Congress of Vienna..." in Paris in 1902. (The Shield Of Time, p. 119)

How does noumenal variability affect phenomenal solidity? On the underlying spatio-temporal level, there is incessant, imperceptible diffraction, probability waves usually reinforcing or cancelling each other but sometimes (a second temporal dimension is implied) abruptly changing their rhythm or powerfully converging on a single point. Consequently, time travelers can arrive in the altered history of a divergent timeline.

This seems the opposite of the "...mesh of tough rubber bands..." model of world-lines that was presented in Time Patrol, p. 15. However, the reader rejoices as the Patrollers' understanding of their continuum deepens in the light of new experiences. Guion, an internal agent of the Patrol, seeking clues to the hypermatrix of  the continuum, interviews other agents about their experiences, knowing that he cannot fully express what he seeks even in Temporal. When a major temporal upheaval does occur, the Patrol might be a little better prepared than otherwise.