The Stretched Horizon and Black Hole Complementarity

TL;DR

This paper develops a framework for understanding black hole evolution using a stretched horizon model, integrating quantum theory, relativity, and thermodynamics, and advocates for black hole complementarity.

Contribution

It introduces a set of postulates for black hole physics and implements them via a stretched horizon approach, differing from 't Hooft's method.

Findings

Dissipative properties arise from microphysical degrees of freedom.

Postulates enable a membrane description for distant observers.

Supports the principle of black hole complementarity.

Abstract

Three postulates asserting the validity of conventional quantum theory, semi-classical general relativity and the statistical basis for thermodynamics are introduced as a foundation for the study of black hole evolution. We explain how these postulates may be implemented in a ``stretched horizon'' or membrane description of the black hole, appropriate to a distant observer. The technical analysis is illustrated in the simplified context of 1+1 dimensional dilaton gravity. Our postulates imply that the dissipative properties of the stretched horizon arise from a course graining of microphysical degrees of freedom that the horizon must possess. A principle of black hole complementarity is advocated. The overall viewpoint is similar to that pioneered by 't~Hooft but the detailed implementation is different.