It occurred to me whilst showering this morning that the reason we can't simply step backwards or forwards in time is because we're in the middle of an intimate sandwich hug with our self of a moment before and our self of a moment hence, and so are they. This would be true for all extended material objects (except for Bose-Einstein condensates). All the rocks, trees, houses; the earth, planets, asteroids, stars, etc. are embraced in sandwich hugs keeping them secure in the time stream. Makes me feel warm and cozy thinking of it, as my part of the planet moves into winter.
I'm sharing this amusing thought for fun, not as a serious physical theory, so please don't rush into criticism (or publication). Yet it's fun to explore it a bit. Feynman suggested that an isolated particle can make an angled turn which reflects it in time, exchanging a gamma ray, etc. to balance the energy and momentum; it continues happily along its "worldline" but now moving "backwards" in time. We see such a backwards-in-time-moving particle as an anti-particle moving "forwards" in time, i.e. along with us. We follow it along and observe its approach to a particle of the same class with which it annihilates, emitting a gamma ray, etc.
Looking at myself from outside of four-dimensional spacetime I appear to be an extended four-dimensional pink worm with extended fringes along its body. There is a long line of hair along one of the fringes. Cut the worm into slices and the fringes become arms, legs, a head with hair, etc. If you've never seen yourself from this point of view take a moment until you can see yourself as a 4D worm. Explore your birth (and before), your growth and your death, etc. Although the physical continuity of the worm along its time axis prevents it from changing its time direction (it is unable to make a sharp enough turn to avoid running into itself), perhaps energy could travel along the worm in the form of vibration. This was explored in the Heinlein short story Life-Line. Thinking of the sandwich hug, though, perhaps I can make and receive some vibrations along the hug line, communicating with my past and future selves for fun and profit.
In preparation for trials of intertemporal communication, it might be a good idea to practice sending and receiving vibrations through some extended lines of sandwich hugs - I'll need some help here, any volunteers?
_Greg (aka Touch)