Comment on 'Hawking Radiation, Unruh Radiation,and the Equivalence Principle'

摘要

In a recent Letter "Hawking Radiation, Unruh Radiation, and the Equivalence Principle" [1] the authors study massless scalar field in the two-dimensional analog of Schwarzschild spacetime. In particular, they study the response rates of the Unruh-DeWitt detector in the Boulware, Unruh, and Hartle-Hawking vacua in this space-time and compare them with those of the accelerated Unruh-DeWitt detector in two-dimensional Minkowski spacetime with the same acceleration. (In fact the calculations in this Letter can be found in Sections 4.4 and 8.3 of Ref. [2], where many of the conclusions of this Letter, e.g., the vanishing of the response in the Boulware vacuum, are given though it contains some errors.)