  The presence of dual active galactic nuclei (AGN) on scales of a few tens of
kpc can be used to study merger-induced accretion on supermassive black holes
(SMBHs) and offer insights about SMBH mergers, using dual AGNs as merger
precursors. In this study, we use the Romulus25 cosmological simulation to
investigate the properties and evolution of dual AGNs. We first analyze the
properties of AGNs ($L_{bol} > 10^{43} \rm erg/s$) and their neighboring SMBHs
(any SMBHs closer than 30 pkpc to an AGN) at $z \leq 2$. This is our underlying
population. Subsequently, we applied the luminosity threshold of $L_{bol} >
10^{43} erg/s$ to the neighboring SMBHs thereby identifying dual and multiple
AGNs in our simulation. We examined the properties and statistics of dual AGNs
in comparison to single AGNs. Our findings indicate an increase in the number
of both single and dual AGNs from lower to higher redshifts. All dual AGNs in
our sample resulted from major mergers. Compared with the single AGN
population, duals are characterized by a lower black hole to halo mass ratio.
We found that the properties of dual AGN host halos, including halo mass,
stellar mass, star formation rate (SFR), and gas mass, are generally consistent
with those of single AGN halos, albeit tending towards the higher end of their
respective property ranges. Our analysis uncovered a diverse array of
evolutionary patterns among dual AGNs, including rapidly evolving systems,
slower ones, and instances where SMBH mergers are ineffective.
