25 citations · 28 across the 12 of their papers we have counts for
12 papers
Time-reversed stochastic inflation in the quantum well
Chiara Animali, Baptiste Blachier, Nanoka Okada +3
Time-reversed stochastic inflation solves the stochastic evolution of the inflationary universe backward in time, by counting the number of e-folds from the end of quantum diffusio…
Primordial black holes in excursion set theory: Formation probabilities, mass functions, and window functions
Hayami Iizuka, Daiki Saito, Koki Tokeshi
We study the mass function of primordial black holes (PBHs) within the excursion-set theory, in which the response of the stochastic density contrast to the variation of the coarse…
Multifield stochastic inflation: Relevance of number of fields in statistical moments
Tomo Takahashi, Koki Tokeshi
In multifield inflation driven by scalar fields, symmetry renders the number of fields irrelevant at classical level. This ceases to be the case once stochastic effects…
Primordial black holes and smooth coarse-graining in excursion set theory
Daiki Saito, Koki Tokeshi
The excursion-set formalism enables us to infer the mass distribution of collapsed objects, such as primordial black holes (PBHs), by the language of stochastic processes. Within t…
Scalar field stochastic dynamics in de Sitter spacetime from exact solutions of quantum deficient oscillators
Yuta Nasuda, Koki Tokeshi, Yuki Watanabe
The stochastic dynamics of a scalar field in de Sitter spacetime can be regarded as a non-perturbative diffusion process, to which exact distribution and correlation functions are…
More fields are different: Stochastic view of multi-field inflationary scenario
Tomo Takahashi, Koki Tokeshi
High-energy physics often motivates multi-field inflationary scenarios where stochastic effects play a crucial role. Peculiar to multi-field models, the noise-induced centrifugal f…
Curvaton distribution from stochastic inflation
Koki Tokeshi
The curvaton paradigm can realise a part of or all the observed curvature perturbation. Based on the stochastic formalism of inflation and closed-form exact distributions therein,…
Exactly solvable stochastic spectator
Masazumi Honda, Ryusuke Jinno, Koki Tokeshi
The stochastic formalism of inflation allows us to describe the scalar-field dynamics in a non-perturbative way. The correspondence between the diffusion and Schrödinger equations…
Why does inflation look single field to us?
Koki Tokeshi, Vincent Vennin
Most high-energy constructions that realise a phase of cosmic inflation contain many degrees of freedom. Yet, cosmological observations are all consistent with single-field embeddi…
Borel resummation of secular divergences in stochastic inflation
Masazumi Honda, Ryusuke Jinno, Lucas Pinol +1
We make use of Borel resummation to extract the exact time dependence from the divergent series found in the context of stochastic inflation. Correlation functions of self-interact…
Superconducting Niobium Calorimeter for Studies of Adsorbed Helium Monolayers
Jun Usami, Koki Tokeshi, Tomohiro Matsui +1
We developed a calorimeter with a vacuum container made of superconducting niobium (Nb) to study monolayers of helium adsorbed on graphite which are prototypical two-dimensional qu…
Window function dependence of the novel mass function of primordial black holes
Koki Tokeshi, Keisuke Inomata, Jun'ichi Yokoyama
We investigate the ambiguity of the novel mass function of primordial black holes, which has succeeded in identifying the black hole mass in a given configuration of fluctuations,…