5 papers
Inflationary background renormalization
Jason Kristiano, Jun'ichi Yokoyama
In cosmic inflation, non-linearities of the curvature perturbation can induce backreaction to the background. To obtain observational predictions at non-linear order on the correct…
Comparing sharp and smooth transitions of the second slow-roll parameter in single-field inflation
Jason Kristiano, Jun'ichi Yokoyama
In single-field inflation, violation of the slow-roll approximation can lead to growth of curvature perturbation outside the horizon. This violation is characterized by a period wi…
Generating large primordial fluctuations in single-field inflation for PBH formation
Jason Kristiano, Jun'ichi Yokoyama
In order to produce appreciable amount of primordial black holes (PBHs), the square amplitude of curvature perturbation must take a large value of , namely, seve…
Note on the bispectrum and one-loop corrections in single-field inflation with primordial black hole formation
Jason Kristiano, Jun'ichi Yokoyama
Primordial black holes can be formed from the collapse of large-amplitude perturbation on small scales in the early Universe. Such an enhanced spectrum can be realized by introduci…
Constraining Primordial Black Hole Formation from Single-Field Inflation
Jason Kristiano, Jun'ichi Yokoyama
The most widely studied formation mechanism of a primordial black hole is collapse of large-amplitude perturbation on small scales generated in single-field inflation. In this Lett…