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arXiv · 2411.12617

Boulware Vacuum vs. Regularity: Thoughts on Anomaly-Induced Effective Action

Kota Numajiri·Kazumasa Okabayashi·Shinji Mukohyama
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Abstract

We examine the vacuum state and its corresponding renormalized stress-energy tensor (RSET) in static horizonless regular spacetime in both two and four dimensions. Using the local field formulation of the anomaly-induced effective action, we show that the regularities of the spacetime and the RSET dictate the appropriate vacuum state. Furthermore, through a case study under the horizonless Bardeen-type spacetime, we demonstrate that the preferred vacuum state is not the Boulware vacuum, but a nontrivial one with a different RSET profile.

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Kota Numajiri, Kazumasa Okabayashi, Shinji Mukohyama. 2024-11-19. Boulware Vacuum vs. Regularity: Thoughts on Anomaly-Induced Effective Action. https://doi.org/10.1103/physrevd.111.085024

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