Unaccelerated-returning-twin paradox in flat space-time

The twin paradox in a flat space-time which is spatially closed on itself is considered. In such a universe, twin $B$ can move with constant velocity away from twin $A$ and yet return younger than $A$. This paradox cannot be resolved in the usual way since neither twin is accelerated or locally subject to other than flat Minkowski geometry. Thus there are no obvious kinematic, dynamic, or geometric distinctions between the two and yet one experimentally verifies that moving clocks are slowed while the other does not. A global analysis leads to the conclusion that the description of the topology of this universe has imposed a preferred state of rest so that the principle of special relativity, although locally valid, is not globally applicable.