system
Given the following post, respond as if you're commenting on Reddit:
human
Is rotation (angular momentum) possible in two dimensions?

I learned about angular momentum in school, and how the vector representation of angular momentum points perpendicular to the plane of rotation, so if a disc rotates in the xy plane, the angular momentum vector associated with it would point in the z axis. 

Does this mean that in a two dimensional universe, it's impossible for rotation to occur because there's no "room" for the angular momentum vector?
gpt
In two dimensions, angular momentum is a scalar (strictly speaking, a pseudoscalar, just as in three dimensions, it's a pseudovector).

Really, in any number of dimensions, angular momentum is given by an n by n antisymmetric matrix.  In three dimensions, this has three independent components, and can be grouped into a (pseudo)vector; in two dimensions, this has one independent component, and can be written as a (pseudo)scalar.