Unravelling lifecycles & physics of radio-loud AGN in the SKA era
  Radio-loud AGN (>10^{22} W/Hz at 1.4 GHz) will be the dominant bright source
population detected with the SKA. The high resolution that the SKA will provide
even in wide-area surveys will mean that, for the first time sensitive,
multi-frequency total intensity and polarisation imaging of large samples of
radio-loud active galactic nuclei (AGN) will become available. The
unprecedented sensitivity of the SKA coupled with its wide field of view
capabilities will allow identification of objects of the same morphological
type (i.e. the entire FR I, low- and high-luminosity FR II, disturbed
morphology as well as weak radio-emitting AGN populations) up to high redshifts
(z~4 and beyond), and at the same stage of their lives, from the youngest
CSS/GPS sources to giant and fading (dying) sources, through to those with
restarted activity radio galaxies and quasars. Critically, the wide frequency
coverage of the SKA will permit analysis of same-epoch rest-frame radio
properties, and the sensitivity and resolution will allow full
cross-identification with multi-waveband data, further revealing insights into
the physical processes driving the evolution of these radio sources. In this
chapter of the SKA Science Book we give a summary of the main science drivers
in the studies of lifecycles and detailed physics of radio-loud AGN, which
include radio and kinetic luminosity functions, AGN feedback, radio-AGN
triggering, radio-loud AGN unification and cosmological studies. We discuss the
best parameters for the proposed SKA continuum surveys, both all-sky and deep
field, in the light of these studies.
