A massless scalar field minimally coupled to gravity and propagating in Schwarzschild
spacetime is considered. After dimensional reduction under spherical symmetry the resulting
2D field theory is canonically quantized and the renormalized expectation values< T ab> of
the relevant energy-momentum tensor operator are investigated. Asymptotic behaviors and
analytical approximations are given for< T ab> in the Boulware, Unruh and Hartle-Hawking
states. Special attention is devoted to the black-hole horizon region where the WKB …

A massless scalar field minimally coupled to gravity and propagating in Schwarzschild
spacetime is considered. After dimensional reduction under spherical symmetry the resulting
2D field theory is canonically quantized and the renormalized expectation values< Tab> of
the relevant energy-momentum tensor operator are investigated. Asymptotic behaviors and
analytical approximations are given for< Tab> in the Boulware, Unruh and Hartle-Hawking
states. Special attention is devoted to the black-hole horizon region where the WKB …