  We examine the generation and evolution of perturbations in a universe
dominated by a fluid with stiff equation of state $p=\rho$. The recently
proposed Holographic Universe is an example of such a model. We compute the
spectrum of scalar and tensor perturbations, without relying on a microphysical
description of the $p=\rho$ fluid. The spectrum is scale invariant deep inside
the Hubble horizon. In contrast, infrared perturbations that enter the Hubble
horizon during the stiff fluid dominated (holographic) phase yield oscillatory
and logarithmic terms in the power spectrum. We show that vector perturbations
grow during the stiff fluid dominated epoch and may result in a turbulent and
anisotropic Universe at the end of the holographic phase. Therefore, the
required period of inflation following the holographic phase cannot be much
shorter than that required in standard inflationary models.
