PIRSA:19110052

Planckian discreteness as a solution of Hawking's information puzzle

APA

Perez, A. (2019). Planckian discreteness as a solution of Hawking's information puzzle. Perimeter Institute. https://pirsa.org/19110052

MLA

Perez, Alejandro. Planckian discreteness as a solution of Hawking's information puzzle. Perimeter Institute, Nov. 15, 2019, https://pirsa.org/19110052

BibTex

          @misc{ pirsa_PIRSA:19110052,
            doi = {10.48660/19110052},
            url = {https://pirsa.org/19110052},
            author = {Perez, Alejandro},
            keywords = {Quantum Gravity},
            language = {en},
            title = {Planckian discreteness as a solution of  Hawking{\textquoteright}s information puzzle},
            publisher = {Perimeter Institute},
            year = {2019},
            month = {nov},
            note = {PIRSA:19110052 see, \url{https://pirsa.org}}
          }
          

Alejandro Perez Centre de Physique Théorique

Collection
Talk Type Scientific Series
Subject

Abstract

In approaches to quantum gravity, where smooth spacetime is an emergent approximation of a discrete Planckian fundamental structure, any standard effective field theoretical description will miss part of the degrees of freedom and thus break unitarity. Here we show that these expectations can be made precise in loop quantum cosmology. Concretely, even when loop quantum cosmology is unitary at the fundamental level, when microscopic degrees of freedom, irrelevant to low-energy cosmological observers, are suitably ignored, pure states in the effective description evolve into mixed states due to decoherence with the Planckian microscopic structure. When extrapolated to black hole formation and evaporation, this concrete example provides a key physical insight for a natural resolution of Hawking's information paradox.