Natural solution to the naturalness problem: The universe does fine-tuning
Yuta Hamada (Department of Physics, Kyoto University, Kyoto 606-8502, Japan); Hikaru Kawai (Department of Physics, Kyoto University, Kyoto 606-8502, Japan); Kiyoharu Kawana (Department of Physics, Kyoto University, Kyoto 606-8502, Japan)
We propose a new mechanism to solve the fine-tuning problem. We start from a multi-local action , where the 's are ordinary local actions. Then, the partition function of this system is given by , where represents the parameters of the system whose Hamiltonian is given by , is the radius of the universe determined by the Friedman equation, and , which is determined by , is a smooth function of . If a value of , , dominates in the integral, we can interpret that the parameters are dynamically tuned to . We show that this indeed happens in some realistic systems. In particular, we consider the strong CP problem, the multiple point criticality principle, and the cosmological constant problem. It is interesting that these different phenomena can be explained by one mechanism.
