Audible curvaton: modulated phase transition as the origin of large-scale curvature perturbations and gravitational wave anisotropies

by Wenyuan Ai (Tsung-Dao Lee Institute, Shanghai Jiao Tong University)

Monday 2 Nov 2026, 16:00 → 17:00 Asia/Shanghai

Abstract: We propose a post-inflationary first-order phase transition modulated by a light spectator field as the origin of primordial large-scale curvature perturbations. Spectator fluctuations acquired during inflation modulate the bubble nucleation history, generating curvature perturbations together with correlated intrinsic gravitational-wave (GW) anisotropies. We show that this mechanism can reproduce the observed amplitude of curvature perturbations while producing a loud stochastic GW background in the frequency bands of space-based detectors such as LISA, Taiji, and TianQin. A concrete benchmark yields strongly enhanced intrinsic GW anisotropies and a local primordial non-Gaussianity signal within reach of future large-scale-structure surveys.

Biography: Wenyuan Ai is an associate professor (tenure-track) at the Tsung-Dao Lee Institute (TDLI), Shanghai Jiao Tong University. He received his Ph.D. degree from the Technical University of Munich in 2019. He carried out postdoctoral research at UC Louvian (CP3, 2019-2021), King's College London (TPPC, 2021-2024), and Austrian Academy of Sciences (HEPHY, 2024-2026). He joined TDLI in February 2026. His research interests are mainly in quantum field theory and the early Universe, in particular cosmological phase transitions, the strong CP problem, non-perturbative and non-equilibrium QFT.

Online Link: https://meeting.tencent.com/dm/t5ibrIFvuenQ

Tencent Meeting ID: 863 955 019

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