  We propose a modified Vicsek-like model to study influence dynamics and
opinion formation in social networks. We work on the premise that opinions of
members of a group may be considered to be analogous to the direction of motion
of a particle in space. The opinions are susceptible to change under the
influence of familiar individuals who maintain similar beliefs. This is unlike
the bounded-confidence models which solely rely on interactions based on
closeness of opinions. The influence network evolves either when similar-minded
individuals acquaint or when they fall out over their beliefs. This yields an
adaptive network to which are assigned dynamic centrality scores and varying
influence strengths. A mix of individuals - rigid and flexible - is assumed to
constitute groups - liberal and conservative. We analyse emergent group
behaviours subject to different initial conditions, agent types, their
densities and tolerances. The model accurately predicts the role of rigid
agents in hampering consensus. Also, a few structural properties of the dynamic
network, which result as a consequence of the proposed model have been
established.
