  The postulates of the eigenstate thermalization hypothesis (ETH) express that
thermalization occurs due to the individual eigenstate of the system's
Hamiltonian. But the ETH put no light on the dynamics that lead toward
thermalization. In this paper, we observe the thermalization of a Bose-Einstein
Condensate (BEC) confined in an optical lattice potential that is embedded in
the harmonic trap. Such optical lattice potential offers local friction to the
oscillating BEC. The spread in the temporal density plot of BEC shows the
thermalization of the BEC. Moreover, we observe that the presence of a
PT-symmetric potential greatly influences the BEC dynamics and the
thermalization of the system. The presence of a PT-symmetric potential offers a
way to manipulate the mean position of the BEC to the desired location and for
a desired length of time.
