A comment on "How the cosmological constant is hidden by Planck scale curvature fluctuations''.

A recent preprint by Wang and Unruh [arXiv:1911.06110] contains a number of criticisms of my paper, "Hiding the cosmological constant" [Phys. Rev. Lett. 123 (2019) 131302, arXiv:1809.08277]. While Wang and Unruh suggest an interesting alternative scenario and raise an important conceptual question, most of their criticisms are incorrect, in part because of misunderstandings about averaging and about the nature of the "foamy" spacetimes considered in my paper.

[1]  W. Unruh,et al.  How the cosmological constant is hidden by Planck scale curvature fluctuations , 2019, 1911.06110.

[2]  D. Pollack,et al.  Causal geodesic incompleteness of spacetimes arising from IMP gluing , 2019, General Relativity and Gravitation.

[3]  V. Moncrief,et al.  Could the universe have an exotic topology? , 2019, Pure and Applied Mathematics Quarterly.

[4]  Mehrdad Mirbabayi.  Topology of cosmological black holes , 2018, Journal of Cosmology and Astroparticle Physics.

[5]  S. Carlip,et al.  Hiding the Cosmological Constant. , 2018, Physical review letters.

[6]  Samuel S. Cree,et al.  Can the fluctuations of the quantum vacuum solve the cosmological constant problem? , 2018, Physical Review D.

[7]  L. Senatore,et al.  Inhomogeneous anisotropic cosmology , 2016, 1602.03520.

[8]  J. Novak,et al.  3+1 geodesic equation and images in numerical spacetimes , 2012, 1208.3927.

[9]  D. Pollack,et al.  Gluing initial data sets for general relativity. , 2004, Physical review letters.

[10]  D. Pollack,et al.  Initial Data Engineering , 2004, gr-qc/0403066.

[11]  B. Krishnan,et al.  Dynamical Horizons and their Properties , 2003, gr-qc/0308033.

[12]  T. Buchert.  On Average Properties of Inhomogeneous Fluids in General Relativity: Dust Cosmologies , 1999, gr-qc/9906015.

[13]  R. Wald.  Asymptotic behavior of homogeneous cosmological models in the presence of a positive cosmological constant , 1983 .

[14]  Sven J. Dickinson,et al.  Geons , 2021, Computer Vision.