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arXiv · 2509.10360

Quantum fields on self-similar spacetimes

Jochen Zahn
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Abstract

We study scalar (not necessarily conformal) quantum fields on self-similar spacetimes. It is shown that in states respecting the self-similarity the expectation value of the stress tensor gives rise to a Lyapunov exponent $\omega_q = 2$, with a leading coefficient which is state-independent and geometric. Three examples for states respecting self-similarity are presented.

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Jochen Zahn. 2025-09-12. Quantum fields on self-similar spacetimes. https://doi.org/10.1088/1361-6382%2Fae3879

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