  The Brownian motion of a test particle interacting with a quantum scalar
field in the presence of a perfectly reflecting boundary is studied in (1 +
1)-dimensional flat spacetime. Particularly, the expressions for dispersions in
velocity and position of the particle are explicitly derived and their
behaviors examined. The results are similar to those corresponding to an
electric charge interacting with a quantum electromagnetic field near a
reflecting plane boundary, mainly regarding the divergent behavior of the
dispersions at the origin (where the boundary is placed), and at the time
interval corresponding to a round trip of a light pulse between the particle
and the boundary. We close by addressing some effects of allowing the position
of the particle to fluctuate.

Quantum Physics;High Energy Physics - Theory