# Bisimilarity and Trace Equivalence in Labelled Transition Systems

I'm a bit confused regarding the relation between trace equivalence and bisimilarity. These lecture notes I found and a few others documents I've read state that "if an LTS is deterministic then two states are bisimilar if they are trace equivalent".

The answer is that the LTS on the left isn't deterministic, as the label (or action) open_door doesn't go to a single state and hence that action is non-deterministic.