# Black hole evaporation: information loss but no paradox

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## Abstract

The process of black hole evaporation resulting from the Hawking effect has generated an intense controversy regarding its potential conflict with quantum mechanics’ unitary evolution. A recent set of works by a collaboration involving one of us, have revised the controversy with the aims of, on one hand, clarifying some conceptual issues surrounding it, and, at the same time, arguing that collapse theories have the potential to offer a satisfactory resolution of the so-called paradox. Here we show an explicit calculation supporting this claim using a simplified model of black hole creation and evaporation, known as the CGHS model, together with a dynamical reduction theory, known as CSL, and some speculative, but seemingly natural ideas about the role of quantum gravity in connection with the would-be singularity. This work represents a specific realization of general ideas first discussed in Okon and Sudarsky (Found Phys 44:114–143, 2014) and a complete and detailed analysis of a model first considered in Modak et al. (Phys Rev D 91(12):124009, 2015).

## Keywords

Black hole evaporation Information paradox Measurement problem Quantum foundation## Notes

### Acknowledgments

We acknowledge useful discussions with Robert Wald, Elias Okon, Philip Pearle, Bernard Kay, George Matsas, Alejandro Perez and the participants of the meeting “Haunted Workshop: Who is afraid of Quantum Theory?”, Tepoztlán, México, 2013. IP thanks ICN-UNAM for providing visiting facilities during his sabbatical year when part of this work was done. Two of the authors, SKM and LO, are supported by DGAPA postdoctoral fellowships from UNAM. We acknowledge partial financial support from DGAPA-UNAM projects IN107412 (DS), and CONACyT project 101712 (DS).

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