Designing Horndeski and the effective fluid approach

We present a family of designer Horndeski models, i.e. models that have a background exactly equal to that of the $\Lambda$CDM model but perturbations given by the Horndeski theory. Then, we extend the effective fluid approach to Horndeski theories, providing simple analytic formulae for the equivalent dark energy effective fluid pressure, density and velocity. We implement the dark energy effective fluid formulae in our code EFCLASS, a modified version of the widely used Boltzmann solver CLASS, and compare the solution of the perturbation equations with those of the code hi_CLASS which already includes Horndeski models. We find that our simple modifications to the vanilla code are accurate to the level of $\sim 0.1\%$ with respect to the more complicated hi_CLASS code. Furthermore, we study the kinetic braiding model both on and off the attractor and we find that even though the full case has a proper $\Lambda$CDM model limit for large $n$, it is not appropriately smooth, thus causing the quasistatic approximation to break down. Finally, we focus on our designer model (HDES), which has both a smooth $\Lambda$CDM limit and well-behaved perturbations, and we use it to perform Markov Chain Monte Carlo analyses to constrain its parameters with the latest cosmological data. We find that our HDES model can also alleviate the soft $2\sigma$ tension between the growth data and Planck 18 due to a degeneracy between $\sigma_8$ and one of its model parameters that indicates the deviation from the $\Lambda$CDM model.Comment: 31 pages, 9 figures, 5 tables, comments welcome. The codes used in the analysis of this paper can be found at https://members.ift.uam-csic.es/savvas.nesseris/efclass.html and at https://github.com/wilmarcardonac/EFCLAS

The traces of anisotropic dark energy in light of Planck

We study a dark energy model with non-zero anisotropic stress, either linked to the dark energy density or to the dark matter density. We compute approximate solutions that allow to characterise the behaviour of the dark energy model and to assess the stability of the perturbations. We also determine the current limits on such an anisotropic stress from the cosmic microwave background data by the Planck satellite, and derive the corresponding constraints on the modified growth parameters like the growth index, the effective Newton's constant and the gravitational slip.Comment: 29 pages, 10 figures; matches version accepted for publication in JCA

Making Political Tourism As an Alternative Model for Hawaii Indigenous Development

The current tourism business model, which is visitor-centered, shows how tourism has strong negative impacts to the host and the place. It happens in many places in the world where tourism business is run by outsiders or with outside capital, and creating conflict with local population. Political tourism is an alternative to the current business model because it looks at the business from the other side: the host-place-centered. Political tourism can be seen as the first step in "indigenizing" capitalism based on local values. The proposed model addresses subsystems in tourism business components, i.e. the transaction, transfer, and treatment systems. It suggests several strategies to make political tourism happen with reference to Native Hawaiians tourism development. It offers some lessons that can be applicable to other places in Asia and the Pacific

New Types of Protein Tyrosine Phosphatase 1B Inhibitors from Marine and Terrestrial Organisms

東北医科薬科大学平成28年