Musician here with terrible pitch guessing ability (but semi-decent composition skillz and good harmony sense). I have always found absolute (or "perfect" pitc

Musician here with terrible pitch guessing ability (but semi-decent composition skillz and good harmony sense). I have always found absolute (or "perfect" pitch) to be misinterpreted in popular culture. I have not actually met a musician with perfect pitch. However, perhaps my definition is too narrow. Would a person with perfect pitch be able to tell the difference between 440 Hz A and 432 Hz A? Would they be able to tell the difference between 440 Hz A and 438 Hz A? If the definition is to be able to tell that a note is only slightly off within some pre-decided tuning system, then I know many people that can do this. The question to me is whether absolute pitch is as it says in the name, "absolute", or is it always limited by some measure of uncertainty? Is there a physical limitation? (Is it 1 Hz, or is it 5 Hz?) Hope someone can explain this. Edit: In the paper, they seem to stick to a pre-decided tuning system. Probably the standard one that we have now (equal spacing based on 13th root of 2 with 440 Hz A).