Insofar as someone using the account with the name of the OP doing the writing, yes. All edits are saved and tracked. If any post was edited, next to the author attribution at the bottom right of the post, there will show a link saying "edited (X time) ago". Click on it and you can see the complete history of revisions.
The actual physical association of an account to a person is, of course, outside the purview of StackExchange.
To show you an example. I just edited the question text that you posted. Now there is a tag next to the author attribution tag displaying your name, that states that this question has been edited. Clicking on the "time" (not my name!) will bring up the revision history for this question.