Research Paper#Cosmology, Primordial Black Holes, Excursion Set Theory🔬 ResearchAnalyzed: Jan 3, 2026 20:13
Impact of Smooth Coarse-Graining on Primordial Black Hole Mass Function
Published:Dec 26, 2025 16:29
•1 min read
•ArXiv
Analysis
This paper investigates how smoothing the density field (coarse-graining) impacts the predicted mass distribution of primordial black holes (PBHs). Understanding this is crucial because the PBH mass function is sensitive to the details of the initial density fluctuations in the early universe. The study uses a Gaussian window function to smooth the density field, which introduces correlations across different scales. The authors highlight that these correlations significantly influence the predicted PBH abundance, particularly near the maximum of the mass function. This is important for refining PBH formation models and comparing them with observational constraints.
Key Takeaways
- •Smooth coarse-graining, using a Gaussian window, introduces correlations in the stochastic noise.
- •These correlations significantly impact the predicted primordial black hole mass function.
- •The abundance of PBHs, especially near the maximum of the mass function, is strongly influenced by these correlations.
- •The study clarifies the role of noise correlations in PBH abundance predictions.
Reference
“The authors find that correlated noises result in a mass function of PBHs, whose maximum and its neighbourhood are predominantly determined by the probability that the density contrast exceeds a given threshold at each mass scale.”