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arXiv · 2501.17936

Aspects of Spatially-Correlated Random Fields: Extreme-Value Statistics and Clustering Properties

Ka Hei Choi·James Creswell·Florian Kuhnel·Dominik J. Schwarz
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Abstract

Rare events of large-scale spatially-correlated exponential random fields are studied. The influence of spatial correlations on clustering and non-sphericity is investigated. The size of the performed simulations permits to study beyond-$7.5$-sigma events (one in $10^{13}$). As an application, this allows to resolve individual Hubble patches which fulfil the condition for primordial black hole formation. It is argued that their mass spectrum is drastically altered due to co-collapse of clustered overdensities as well as the mutual threshold-lowering through the latter. Furthermore, the corresponding non-sphericities may imply possibly large changes in the initial black hole spin distribution.

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Ka Hei Choi, James Creswell, Florian Kuhnel, Dominik J. Schwarz. 2025-01-29. Aspects of Spatially-Correlated Random Fields: Extreme-Value Statistics and Clustering Properties. https://doi.org/10.1103/n3tr-t6dc

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