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arXiv · 2507.17579

Bispectrum of induced gravitational waves in the poltergeist mechanism

Han-Wen Hu·Cheng-Jun Fang·Zhen-Min Zeng·Zong-Kuan Guo
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Abstract

In the poltergeist mechanism the enhancement of induced gravitational waves (GWs) occurs due to a sudden transition from an early matter-dominated era to the radiation-dominated era. In this work, we calculate the bispectrum of induced GWs from the poltergeist mechanism by adopting the sudden transition approximation. We find that the tensor bispectrum peaks either in the equilateral or squeezed configurations, depending on scales. Such a characteristic behavior enables us to distinguish it from that from other GW generation mechanisms.

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Han-Wen Hu, Cheng-Jun Fang, Zhen-Min Zeng, Zong-Kuan Guo. 2025-07-23. Bispectrum of induced gravitational waves in the poltergeist mechanism. https://doi.org/10.1103/j3nw-rt5p

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