Do We Really Understand the Cosmos?
  Our knowledge about the universe has increased tremendously in the last three
decades or so --- thanks to the progress in observations --- but our
understanding has improved very little. There are several fundamental questions
about our universe for which we have no answers within the current,
operationally very successful, approach to cosmology. Worse still, we do not
even know how to address some of these issues within the conventional approach
to cosmology. This fact suggests that we are missing some important theoretical
ingredients in the overall description of the cosmos. I will argue that these
issues --- some of which are not fully appreciated or emphasized in the
literature --- demand a paradigm shift: We should not think of the universe as
described by a specific solution to the gravitational field equations; instead,
it should be treated as a special physical system governed by a different
mathematical description, rooted in the quantum description of spacetime. I
will outline how this can possibly be done.
