The study of the formation, or seeding, of supermassive black holes in galaxies has been a delicate balance between details and computational expense. Cosmological simulations can resolve the structures of galaxies that might form black holes, such as dense metal-poor gas clouds, but are much more burdensome to run compared to a simple semi-analytic model. In my work (with Rachel Somerville, Aklant Bhowmick, Aaron Yung, and Viraj Pandya), I use a combination of the detailed properties of the BRAHMA cosmological simulations and the computational flexibility of the Santa Cruz semi-analytic model.

Within this framework, I have shown that signatures of seeding are most discernible in black holes ${\displaystyle \begin{array}{c}\sim <{10}^5{M}_{\odot }\end{array}}$and halo masses ${\displaystyle \begin{array}{c}\sim <{10}^{10}{M}_{\odot }\end{array}}$meaning it is a very difficult task to use electromagnetic observations to uncover how these black holes are born. Perhaps gravitational wave observations are our only hope…