Spacetime Foam and the Cosmological Constant


Carlip, S. (2019). Spacetime Foam and the Cosmological Constant. Perimeter Institute. https://pirsa.org/19110107


Carlip, Steve. Spacetime Foam and the Cosmological Constant. Perimeter Institute, Nov. 21, 2019, https://pirsa.org/19110107


          @misc{ pirsa_19110107,
            doi = {10.48660/19110107},
            url = {https://pirsa.org/19110107},
            author = {Carlip, Steve},
            keywords = {Cosmology, Quantum Fields and Strings, Quantum Gravity},
            language = {en},
            title = {Spacetime Foam and the Cosmological Constant},
            publisher = {Perimeter Institute},
            year = {2019},
            month = {nov},
            note = {PIRSA:19110107 see, \url{https://pirsa.org}}

Steve Carlip University of California System


I describe a radical proposal for the cosmological constant problem: perhaps Lambda really is very large, but is "hidden" in Planck-scale fluctuations of geometry and topology. I show that an enormous set of initial data describe a universe with such a hidden cosmological constant at an initial time. The question of whether this structure is preserved under time evolution is still open, but I provide some evidence that it may be. I close with a discussion of open questions that might lead to further insight (or perhaps kill the idea).