The case for primordial black holes as dark matter

Understand

The aim of this paper is to present the case that stellar mass primordial black holes make up the dark matter component of the Universe.

• A near critical density of compact bodies implies that most lines of sight will be gravitationally microlensed, and the paper focuses on looking for the predicted effects on quasar brightness and spectral variations.
• These signatures of microlensing include the shape of the Fourier power spectrum of the light curves, near achromatic and statistically symmetric variations, and the absence of time dilation in the timescale of variability.
• For spectral changes, as the continuum varies there should be little corresponding change in the strength of the broad lines.