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arXiv · 2509.16991

Exact quasinormal modes in Grumiller spacetime

Li-Qin Mi·Zhong-Heng Li
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Abstract

The Grumiller metric is an effective model for gravity at large distances and plays a significant role in constructing galactic models and explaining dark matter. Here, in Grumiller spacetime, we analytically compute the quasinormal-mode frequencies and wave functions for massless particles with spin $\leq 2$ by introducing a new transformation relation. Our findings indicate that the quasinormal-mode frequencies are identical for different fermions with the same quantum number $n$. Notably, no bosonic quasinormal modes associated with Heun polynomials were found. Furthermore, for a given quasinormal-mode frequency, the corresponding particles exhibit a $2(n + 1)$-fold degeneracy. These results provide a theoretical basis for the mutual simulation of fermionic waves.

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Li-Qin Mi, Zhong-Heng Li. 2025-09-21. Exact quasinormal modes in Grumiller spacetime. https://arxiv.org/abs/2509.16991

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