I am not sure whether or not we can, for "duration of the time", write just "duration".
Here is the text which I encountered the problem in writing:
The expressions "bosom friends" and "bosom buddy" refer to the closeness of relationship between two or more persons as friends; the expressions do not refer to the time from when such relationship subsisted. I think the crux of the question is not the closeness of the relationship, but the duration of the time during which such relationship subsisted.
Reference: see my comment to the answer of BiscuitBoy to the question entitled "Term or idiom to describe a best friend since your childhood". Link: Term or idiom to describe a best friend since your childhood
My question is: could I have written just "duration" for "duration of the time"?