TY  - JOUR
PB  - SciPost Foundation
DO  - 10.21468/SciPostPhys.14.5.109
TI  - A tail of eternal inflation
PY  - 2023/05/12
UR  - https://scipost.org/SciPostPhys.14.5.109
JF  - SciPost Physics
JA  - SciPost Phys.
VL  - 14
IS  - 5
SP  - 109
A1  - Cohen, Timothy
AU  - Green, Daniel
AU  - Premkumar, Akhil
AB  - Non-trivial inflaton self-interactions can yield calculable signatures of primordial non-Gaussianity that are measurable in cosmic surveys. We calculate the non-Gaussian corrections to Stochastic Inflation within the framework of Soft de Sitter Effective Theory, from which we derive the associated probability distribution for the scalar fluctuations. As a consequence of this new result, we show that the phase transition to slow-roll eternal inflation is often incalculable in these models. Instead, this transition is sensitive to the non-Gaussian tail of the distribution of scalar fluctuations, which probes physics inside the horizon, potentially beyond the cutoff scale of the Effective Field Theory of Inflation. We delineate the parameter space consistent with current observations and weak coupling at horizon crossing in which the large fluctuations relevant for eternal inflation can only be determined by appealing to a UV completion. We also argue that this breakdown of the perturbative description is required for the de Sitter entropy to reflect the number of de Sitter microstates.
ER  -

@Article{10.21468/SciPostPhys.14.5.109,
	title={{A tail of eternal inflation}},
	author={Timothy Cohen and Daniel Green and Akhil Premkumar},
	journal={SciPost Phys.},
	volume={14},
	pages={109},
	year={2023},
	publisher={SciPost},
	doi={10.21468/SciPostPhys.14.5.109},
	url={https://scipost.org/10.21468/SciPostPhys.14.5.109},
}