  The nature and origin of turbulence and magnetic fields in the intergalactic
space are important problems that are yet to be understood. We propose a
scenario in which turbulent flow motions are induced via the cascade of the
vorticity generated at cosmological shocks during the formation of the large
scale structure. The turbulence in turn amplifies weak seed magnetic fields of
any origin. Supercomputer simulations show that the turbulence is subsonic
inside clusters/groups of galaxies, whereas it is transonic or mildly
supersonic in filaments. Based on a turbulence dynamo model, we then estimate
that the average magnetic field strength would be a few microgauss inside
clusters/groups, approximately 0.1 microgauss around clusters/groups, and
approximately 10 nanogauss in filaments. Our model presents a physical
mechanism that transfers the gravitation energy to the turbulence and magnetic
field energies in the large scale structure of the universe.
