A Modest View of the Black Hole Information Paradox

TL;DR

This paper argues that the black hole information paradox is more a conflict between theoretical models than a physical problem, emphasizing the limited applicability of semi-classical calculations and the nature of quantum states.

Contribution

The paper offers a modest perspective that questions the physical significance of the black hole information paradox and highlights the conceptual limitations of current models.

Findings

The paradox may not have direct observational consequences.

Unitarity is a property of models, not necessarily of nature.

Semi-classical calculations have limited applicability.

Abstract

Thirty years ago, John Preskill concluded "that the information loss paradox may well presage a revolution in fundamental physics" and mused that "Conceivably, the puzzle of black hole evaporation portends a scientific revolution as sweeping as that that led to the formulation of quantum theory in the early 20th century." Many still agree with this assessment. On the other hand, it seems to me the "paradox" has little to do with the physical world but rather, at best, simply points out the possible inconsistency of two, already disparate, theories (mathematical models) of nature, general relativity and quantum mechanics, with virtually no conceivable observational consequences. The information paradox hinges on the concepts of a pure quantum state, the unitarity of quantum mechanics, and Hawking's semi-classical calculation of black hole evaporation. I used the qualifier "at best" above because, for me, the concept of a quantum state is far more restrictive than required by the paradox while unitarity is not a property of nature but rather of a mathematical model and is already violated by the process of making a measurement. Furthermore, the semi-classical calculation of Hawking is surely of limited applicability.