Rindler Noise in the Flat Spacetime with a Boundary. I

The vacuum ~oise of a quantum field as viewed by a uniformly accelerated observer is studied in the flat spacetime with a static boundary perpendicular to the direction of acceleration. The noise consists of two terms; one is the ordinary thermal term that satisfies the KMS condition, and the other is a new term that represents the boundary effect. It is shown that the latter effectiyely vanishes as the position of the boundary tends to the edge of the Rindler wedge associated with the observer. This special property can be interpreted as the consequence of a specific type of interference among various modes of the field. These results hold regardless of the dimension of the spacetime for massive as well as massless fields.