  We propose a new scenario of nonequilibirum multiverse. We quantified the
potential landscape and the flux landscape for the Bousso-Polchinski type of
multiverse. The potential landscape quantifies the weight of each universe.
When the terminal vacuum with zero (flat) or negative cosmological constant
(AdS) have a chance to tunnel back to the normal universes with positive
cosmological constant (dS) through the bounce suggested by the recent studies,
the detailed balance of the populations of the multiverse can be broken. We
found that the degree of the detailed balance breaking can be quantified by the
underlying average flux and associated flux landscape, which gives arise to the
dynamical origin of irreversibility and the arrow of time. We also showed that
the steady state of the multiverse is maintained by the thermodynamic cost
quantified by the entropy production rate which is associated to the flux. This
gives arise to thermodynamic origin of time irreversibility. We show that
terminal vacuum universes can have dominant weights or lowest potentials giving
arise to a funnel shaped potential landscape, while terminal vacuum universes
together with other normal universes including ours can form dominant cycles
giving arise to a funnel shaped cycle flux landscape. This indicates that even
our universe may not be distinct from others based on the probability measure,
it may lie in the dominant cycle(s), leading to higher chance of being found.
This may provide an additional way beyond the anthropological principle for
identifying our universe.
