My lysdexia above has a variety of origins. Indeed, this subject is littered with banana peels on which the unwary can slip, so it is probably pedagogically useful to list them.

The main reason for my slip, writing *e ^{ipc}* instead
of

and thus in the commutators of the corresponding operators:

where an extra factor of -*i* is traditionally thrown in to further
confuse the uninitiated.

Thus in the state *e ^{-icp + ibq} *|0>, the expectation
value of position is

Second, there is a somewhat arbitrary convention about whether we think
of a point in phase space with momentum *b* and position *c*
and as being the point *c*+*ib* in the complex plane, or *b*+*ic*.
Time evolution for the harmonic oscillator amounts to having our complex
plane rotate as time passes, and if we use *c*+*ib* the plane
will rotate *clockwise*, while if we use *b*+*ic* the plane
will rotate *counterclockwise*. The former means that after a time
*t*, the point *c*+*ib* will evolve to

while the latter means that after a time *t*, the point *b*+*ic*
will evolve to

The latter seems nicer to me, which is another reason for my slip, but we seem to be working with the former convention.