16 citations · 21 across the 4 of their papers we have counts for
5 papers
Light deflection in Observation: Angle differences between two null geodesics on the de Sitter spacetime with multi-lensing objects
Rio Saitou, Hiromi Saida
We derive angle differences between two null geodesics, propagating from light sources to an observer, on the de Sitter spacetime with multi-lensing objects. Assuming the lensing o…
Constraints on the dark mass distribution surrounding Sgr A*: simple analysis for the redshift of photons from orbiting stars
Yohsuke Takamori, Shogo Nishiyama, Takayuki Ohgami +3
Sagittarius A* (Sgr A*) is the central supermassive black hole with the mass in the Milky Way and stars are orbiting around it. In May 2018, one of th…
Stochastic approach to de Sitter instability and eternal inflation
Rio Saitou
We investigate when effective theories of a scalar field on (quasi-)de Sitter background break down through the stochastic formalism. We derive the Fokker-Planck equation leaving t…
Inflationary spectral tilts as a result of the dilatation symmetry breaking
Pisin Chen, Jiro Matsumoto, Rio Saitou
We derive the spectral indices and their runnings of single inflation models by a new approach. We perform a dilatation transformation to the linear cosmological perturbations and…
Hamiltonian analysis of nonprojectable Hořava-Lifshitz gravity with symmetry
Shinji Mukohyama, Ryo Namba, Rio Saitou +1
We study the nature of constraints and count the number of degrees of freedom in the nonprojectable version of the extension of Hořava-Lifshitz gravity, using the standard m…