The Paradox of the Two Joes

I have been thinking about the concept of memories. They are these strange little invisible threads that hold together our view of our entire persona. Our whole life is woven of experiences (touched, tasted, smelled, heard and seen) This is somehow distilled into a data storage medium and kept in a vault in our brain somewhere, like [Steven King's "Dream Catcher" reference] a "memory warehouse." So these bits of data, how accurate are they as representations of actual events? Take even the simplest event, a birthday party, a fishing trip, or the viewing of a film, each one of these events will be dictated and translated into the data banks of our memory in unique ways. Emotions help to give them a rating of importance and where and how they are stored. somethings just seem to get lost in the shuffle.

If we are completely honest with ourselves, we will have to admit that not all the memories that we have are accurate. Processing errors do happen. Some events actually took place in a different set of conditions, time, weather, colors, people and participants might have been different. Some psychologists have theorized that people "paint" their memory into existence.

I would like to set up a scenario for you:

Imagine that a man named Joe is trying to remember his childhood. He has never had any problems with mental illness or mind-altering drug use, and he is healthy in every way. Joe is 27 years old, so his childhood is not too distant from his vantage point. Now imagine that in a parallel universe there exists another Joe, with slightly different memories (again this Joe has no mental illness, history of drug use and is perfectly healthy in every way.) We will call the first Joe [Joe 1] the second [Joe 2.]

At the precise time that Joe 1 tries to recall his childhood an event occurs, (we will just call it a quantum event or quantum shift.) This event causes Joe 2 to be swapped with Joe 1. (or possibly Joe 1's mind with that of Joe 2. The memories of Joe 1 transferred into Joe 2 and vice versa.)

A few questions:

1.) Does Joe 1 or 2 know that the switch has occured? If so, how?
2.) Does anoyone else notice? If so, how?

In all actuallity this event could happen to any one of us, and if it did, by some querk of physics, how would we know it? Would not our only measure of the shift be lost by the act of shifting? Memories might linger, thoughts might haunt the Joes for some time, but which would ever be able to truly discern what had happened?

I order to further explore this paradox one must have an understanding of the Multiple Worlds Interpretation of Quantum mechanics. The Everett/Wheeler model.

My point is this... How sure are you that the world you lived in today was that same world [or world-line] you lived in yesterday? How sure are you of the accuracy of your memories? And if we travle between similar but different worlds, how can any of us really know where we started?