123 citations · 175 across the 8 of their papers we have counts for
11 papers · 1 filter
Reheating after relaxation of large cosmological constant
Paul Martens, Shinji Mukohyama, Ryo Namba
We present a cosmological model of an early-time scenario that incorporates a relaxation process of the would-be large vacuum energy, followed by a reheating era connecting to the…
Positivity vs. Lorentz-violation: an explicit example
Katsuki Aoki, Shinji Mukohyama, Ryo Namba
We show how a class of multi-field scalar-field theories in a Lorentz-breaking background imposes consistency conditions on its effective theory of a single field and provides an e…
Partial UV Completion of from a Curved Field Space
Shinji Mukohyama, Ryo Namba
The -essence theory is a prototypical class of scalar-field models that already gives rich phenomenology and has been a target of extensive studies in cosmology. General forms o…
Role of matter in gravitation: going beyond the Einstein-Maxwell theory
A. Emir Gumrukcuoglu, Ryo Namba
For field theories in curved spacetime, defining how matter gravitates is part of the theory building process. In this letter, we adopt Bekenstein's multiple geometries approach to…
Unified Dark Matter, Dark Energy and Baryogenesis via a "Cosmological Wetting Transition''
Robert Brandenberger, Juerg Froehlich, Ryo Namba
In a recent publication \cite{us}, a cosmological scenario featuring a scalar field, , that is a source for Dark Matter and Dark Energy has been proposed. In this paper, a concr…
Solving the flatness problem with an anisotropic instanton in Hořava-Lifshitz gravity
Sebastian F. Bramberger, Andrew Coates, João Magueijo +3
In Hořava-Lifshitz gravity a scaling isotropic in space but anisotropic in spacetime, often called anisotropic scaling with the dynamical critical exponent z=3, lies at the base of…