"Can somebody explain in plain English"\

Not even those who believe in and developed this idea can explain it 'clearly', because some of it depends on complex math, and some of it is merely linguistic....manipulation of terms to create metaphor that we think we understand.

We can create the concept of "traveling back in time", but we can't really imagine what that would be like, or avoid all the contradictions involved. In physics, some of these ideas DO represent some interpretations of odd observations and math...but don't really translate easily into something we can 'explain', the temptation notwithstanding.

   My mother used to say her favorite color was "sky-blue pink", and we all see commonly used terms in that name, but it really makes little sense if you try to imagine it. I once found a ceramic tile that faded from sky-ish 'blue' to a 'pinkish' hue in various areas....but it was only a blending OF colors...not a color. Language can discuss things that are not exactly 'real'.