Speaker: Alejo Martinez-Sansigre
Location: Cerro Calan, Santiago, Chile
Every massive galaxy is believed to harbour a supermassive black hole in its centre. These can grow by accretion or by mergers, and these
processes will leave different imprints in the spin history of the supermassive black holes. I will discuss several different approaches to
estimating the cosmic spin of supermassive black holes, using the mean radiative efficiency of quasars, but more informatively by using radio
observations. These radio observations trace the jets produced by supermassive black holes, and using recent theoretical models we have
shown that black hole spin can explain the varying jet powers observed amongst active galactic nuclei, as well as the radio luminosity function.
We can therefore use the radio observations to infer the cosmic spin history of the most massive black holes, and I will discuss the
implications for the processes by which they grow.