| Abstract 摘要 | We consider a static thin shell wormhole collides with another thin shell consisting of ordinary matter. By employing the geometrical constraint, which leads to the conservation of energy and momentum, we show that the state after the collision can be solved from the initial data. In the low speed approximation, the solutions are rather simple. The shell may either bounce back or pass through the wormhole. In either case, the wormhole shrinks right after the collision. In the ``bouncing'' case, a surprising result is that the radial speeds before and after the collision satisfy an addition law. Once the shell passes through the wormhole, we find that the shell always expands. However, the expansion rate is the same as the collapsing rate right before the collision. |
