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In this essay, we discuss the fine-tuning problems of the Higgs mass and the cosmological constant. We argue that these are indeed legitimate problems, as opposed to some other problems that are sometimes described using similar vocabulary. We then notice, following Tom Banks, that the problems become less compelling once we recognize that the Universe contains quantum gravity, and thus isnt fundamentally described by bulk QFT. Embracing this solution requires a reversal of the standard arrows UV->IR and past->future. The first reversal is familiar from AdS/CFT. The second reversal refers more specifically to our Universes cosmology, and is clearly in potential conflict with the Second Law of Thermodynamics. In the final part of the essay, we attempt to defuse this conflict, suggesting that the Second Law can arise naturally from de Sitter boundary conditions at future infinity.
Maximally symmetric curved-brane solutions are studied in dilatonic braneworld models which realise the self-tuning of the effective four-dimensional cosmological constant. It is found that no vacua in which the brane has de Sitter or anti-de Sitter
Robinson-Wilczeks recent work shows that, the energy momentum tensor flux required to cancel gravitational anomaly at the event horizon of a Schwarzschild-type black hole has an equivalent form to that of a (1+1)-dimensional blackbody radiation at th
We investigate the generalized second law of thermodynamics (GSL) in generalized theories of gravity. We examine the total entropy evolution with time including the horizon entropy, the non-equilibrium entropy production, and the entropy of all matte
We study the dS/CFT duality between minimal type-A higher-spin gravity and the free Sp(2N) vector model. We consider the bulk spacetime as elliptic de Sitter space dS_4/Z_2, in which antipodal points have been identified. We apply a technique from ar
Light scalars in inflationary spacetimes suffer from logarithmic infrared divergences at every order in perturbation theory. This corresponds to the scalar field values in different Hubble patches undergoing a random walk of quantum fluctuations, lea