Quantum fluctuations as the seeds of cosmic structure.
Although the inflationary predictions for the primordial power spectrum of density inhomogeneities seem very successful, there is an obscure part in our understanding of the emergence of the seeds of cosmic structure: How does a universe which at one pint in time is described by a state that is fully homogeneous and isotropic, evolve into a state that is not, given that the dynamics does not contain any source for the undoing of such symmetry? We will discuss an approach that offers a resolution of the issue in the context of proposals to deal with the measurement problem in quantum mechanics. We will see that the approach naturally resolves the difficulties raised by the lack of observation of tensor modes.