By default, LaTex inserts a longer, intersentence space after a period. The exception is if the period follows a capital letter, in which case an interword space is assumed. This thread describes the situation (and how to work around it) nicely:
However, I never follow acronyms with periods, so this behavior is a constant source of annoyance. It means that I always have to carefully proofread my document to make sure that I haven't forgotten the critical
\@ between my uppercase acronyms and trailing periods. Not only does this waste my time, it violates the very good idea that content and the busywork of formatting should be kept separate.
Is there any way to modify this default behavior?
If the string ". " occurs in my document, I always want LaTex to use an intersentence space.