  In this work, we investigate the effect of social media on the process of
opinion formation in a human population. This effect is modeled as an external
field in the dynamics of the two-dimensional Sznajd model with a probability P
for an agent to follow the social media. We investigate the evolution of
magnetization, the distribution of decision time and the average relaxation
time in the presence of the external field. Our results suggest that the
average relaxation time on the lattice of size L follows a power law, where the
exponent depends on the probability P. We also show that phase transition
between two distinct states of the system decreases for any initial
distribution of the opinions as the probability P is increasing. For a critical
point of P ~ 0.18, no phase transition is observed and the system evolves to a
dictatorship regardless of the initial distribution of the opinions in the
population.
