PIRSA:11090067

Cosmology Meets Quantum Gravity: a Chiral Signature in the CMB?

APA

Magueijo, J. (2011). Cosmology Meets Quantum Gravity: a Chiral Signature in the CMB?. Perimeter Institute for Theoretical Physics. https://pirsa.org/11090067

MLA

Magueijo, Joao. Cosmology Meets Quantum Gravity: a Chiral Signature in the CMB?. Perimeter Institute for Theoretical Physics, Sep. 08, 2011, https://pirsa.org/11090067

BibTex

          @misc{ scivideos_PIRSA:11090067,
            doi = {10.48660/11090067},
            url = {https://pirsa.org/11090067},
            author = {Magueijo, Joao},
            keywords = {Quantum Gravity},
            language = {en},
            title = {Cosmology Meets Quantum Gravity: a Chiral Signature in the CMB?},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2011},
            month = {sep},
            note = {PIRSA:11090067 see, \url{https://scivideos.org/index.php/pirsa/11090067}}
          }
          

Joao Magueijo Imperial College London

Talk numberPIRSA:11090067
Source RepositoryPIRSA
Collection

Abstract

Cosmology and quantum gravity have not always had the smoothest of interactions. As a case in point I'll summarize the calculation behind the prediction of tensor modes in inflationary universes and discuss the difficulties found in recasting this calculation in terms of Ashtekar-Barbero-Immirzi variables. Contrary to the belief that ``inflation is shielded from quantum gravity'', novelties are found, leading to the interesting prediction of a chiral signature in the gravitational wave background, proportional to the imaginary part of the Immirzi parameter. This would leave a distinctive imprint in the polarization of the cosmic microwave background. On a more theoretical level, our remarks shed light on matters permeating quantum gravity, such as the inner product, the ground state (which we prove is NOT the Kodama state) and ordering issues.