Primordial black holes and stochastic gravitational wave background from inflation with a noncanonical spectator field

Cai, Rong-Gen; Chen, Chao; Fu, Chengjie

doi:10.1103/physrevd.104.083537

Cited by 74 publications

(32 citation statements)

References 116 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…While, for the very light PBHs (M ≤ 10 15 g), their Hawking radiation can be strong [27,28] and have already evaporated, the Hawking-radiated particles may influence physical processes in the early Universe, like Big Bang Nucleosynthesis [29][30][31]. Meanwhile, with the dramatic developments of GW experiments, a lot of attentions focus on the GW signals coming from PBHs associated with the binary mergers [18,20,[32][33][34][35] and scalar perturbations [36][37][38][39][40][41][42][43][44][45][46][47][48][49]. In summary, PBHs can be a promising needle to detect physics in the early and late Universe.…”

Section: Pbh Bubblesmentioning

confidence: 99%

Cosmological Standard Timers from Unstable Primordial Relics

Cai¹,

Chen²,

Ding³

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

In this article we study a hypothetical possibility of tracking the evolution of our Universe by introducing a series of the so-called standard timers. Any unstable primordial relics generated in the very early Universe may serve as the standard timers, as they can evolve through the whole cosmological background until their end while their certain time-varying properties could be a possible timer by recording the amount of physical time elapsed since the very early moments. Accordingly, if one could observe these quantities at different redshifts, then a redshift-time relation of the cosmic history can be attained. To illustrate such a hypothetical possibility, we consider the primordial black hole bubbles as a concrete example and analyze the mass function inside a redshifted bubble by investigating the inverse problem of Hawking radiation. To complete the analyses theoretically, the mass distribution can serve as a calibration of the standard timers.

show abstract

Section: Pbh Bubblesmentioning

confidence: 99%

Cosmological Standard Timers from Unstable Primordial Relics

Cai¹,

Chen²,

Ding³

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…(4.45) and the possible oscillatory counterpart in the post-inflationary Ω rad GW . The same line of thought applies to [100,101] where visually similar shapes have been numerically computed for models with resonances. It is likely that our formalism and results are applicable there.…”

Section: 48)mentioning

confidence: 92%

Primordial gravitational waves from excited states

Fumagalli,

Palma,

Renaux-Petel

et al. 2021

Preprint

View full text Add to dashboard Cite

We show that a scalar excited state with large occupation numbers during inflation leads to an enhancement of tensor modes and a characteristic pattern of orderone oscillations in the associated stochastic gravitational wave background (SGWB) sourced during inflation. An effective excited state, i.e. a departure from the Bunch-Davies vacuum, can emerge dynamically as the result of a transient non-adiabatic evolution, e.g. a sharp feature along the inflationary history. We provide an explicit example in a multifield context where the sharp feature triggering the excited state is identified with a strong turn in the inflationary trajectory. En passant, we derive a universal expression for the tensor power spectrum sourced at second order by an arbitrary number of scalar degrees of freedom during inflation, crucially taking into account the nontrivial structure of the Hilbert space in multifield setups. The SGWB sourced during inflation can overcome the standard scalar-induced SGWB sourced at horizon re-entry of the fluctuations after inflation, while being less constrained by perturbativity and backreaction bounds. In addition, one may entertain the possibility of detecting both since they peak at different frequencies exhibiting oscillations with distinct periods.

show abstract

“…Moreover, there are plentiful nonperturbative phenomenologies to explore. For example, various resonances during inflation have been studied extensively in [43][44][45][46][47][48][49][50]. It is interesting to investigate rich behaviors of their non-Gaussian tails and other cases in follow-up studies.…”

Section: 𝜋| ≡ 𝑑𝜙(𝑛) 𝑑𝑛mentioning

confidence: 99%

One Small Step for an Inflaton, One Giant Leap for Inflation: a novel non-Gaussian tail and primordial black holes

Cai,

Ma,

Sasaki

et al. 2021

Preprint

View full text Add to dashboard Cite

We report a novel prediction from single-field inflation that even a tiny step in the inflaton potential can change our perception of primordial non-Gaussianities of the curvature perturbation. Our analysis focuses on the tail of probability distribution generated by an upward step transition between two stages of slow-roll evolution. The nontrivial background dynamics with off-attractor behavior is identified. By using a non-perturbative δN analysis, we explicitly show that a highly non-Gaussian tail can be generated by a tiny upward step, even when the conventional nonlinearity parameters f local NL , g local NL , etc. remain small. With this example, we demonstrate for the first time the sensitive dependence of non-perturbative effects on the tail of probability distribution. Our scenario has an inconceivable application to primordial black holes by either significantly boosting their abundance or completely forbidding their appearance.

show abstract

Primordial black holes and stochastic gravitational wave background from inflation with a noncanonical spectator field

Cited by 74 publications

References 116 publications

Cosmological Standard Timers from Unstable Primordial Relics

Cosmological Standard Timers from Unstable Primordial Relics

Primordial gravitational waves from excited states

One Small Step for an Inflaton, One Giant Leap for Inflation: a novel non-Gaussian tail and primordial black holes

Contact Info

Product

Resources

About