My newest work titled “Instantons and the Hartle-Hawking-Madacena proposal for dS/CFT” has appeared in http://arxiv.org/pdf/1406.6148.pdf.

Together with S. de Haro, we tested the Maldacena proposal for the Hartle-Hawking late time quantum state in an asymptotically de Sitter universe. In particular, we calculated the on-shell action for scalar instantons on the southern hemisphere of the four-sphere and compare the result with the renormalized on-shell action for scalar instantons in EAdS4. The two results agree provided the corresponding instanton moduli as well as the curvature radii are analytically continued.
The instanton solutions in de Sitter are novel and satisfy mixed boundary conditions. We also pointed out that instantons on S4 calculate the regularized volume of EAdS4, while instantons on EAdS4 calculate the volume of S4, where the boundary condition of the instanton in one space is identified with the radius of curvature of the other. We finally briefly discussed the implications of the above geometric property of instantons for higher-spin holography.