33 citations · 404 across the 47 of their papers we have counts for
47 papers
Ostrogradsky's Theorem is Incompatible with Background Independence in Quantum Gravity
Ken-ji Hamada
Ostrogradsky's theorem shows that higher-derivative dynamical systems inevitably yields a Hamiltonian featuring a ghost mode that is unbounded from below. However, we argue that th…
Quantum Gravity Effective Action Provides Entropy of The Universe
Ken-ji Hamada
The effective action in renormalizable quantum theory of gravity provides entropy because the total Hamiltonian vanishes. Since it is a renormalization group invariant that is cons…
Study of Nonlinear Evolution of Spacetime Fluctuations in Quantum Gravity Inflation for Deriving Primordial Spectrum
Ken-ji Hamada
We study the evolution of quantum fluctuations of gravity around an inflationary solution in renormalizable quantum gravity, in which the initial scalar-fluctuation dominance is sh…
Revealing A Trans-Planckian World Solves The Cosmological Constant Problem
Ken-ji Hamada
The Planck scale is usually believed to be an unpassable wall. Putting a cutoff there and thinking of it as a quantized spacetime entity shows that. However, this is exactly the ca…
Diffeomorphism Invariance Demands Conformal Anomalies
Ken-ji Hamada
We study a series of the Wess-Zumino actions obtained by repeatedly integrating conformal anomalies with respect to the conformal-factor field that appear at higher loops. We show…
Localized massive excitation of quantum gravity as a dark particle
Ken-ji Hamada
We construct a static and spherical excited state without singularities in renormalizable quantum gravity with background-free nature asymptotically. Its diameter is given by a cor…