Multiple tape TM

Multiple heads, multiple tapes, one control logic. A similar interleaving argument can be used to multiplex these tracks on a single track if the heads are tied together. If they are not tied together, then shifting can be used to move information around to avoid head collisions.

$$\centerline{ \begin{tabular} {ccccc} head one region & & h... ...yyyyyyyy & $\ldots$\space & zzzzzzzzzzzzzzz \\ \end{tabular}}$$ (6)