Daniel Sudarsky

We  will  briefly review  the  issue  of    "information loss"    during  the Hawking   evaporation of a  black hole,  and  argue that    the  quantum dynamical  reduction  theories, which  have  been  developed to  address the   measurement problem  in quantum mechanics,  possess the  elements to  diffuse the ``paradox”  at the qualitative  and  at   the  quantitative  level, leading to what  seems  to be an overall  coherent  picture.  

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?

Is aether technically natural?
I will discuss whether higher energy Lorentz violation should be considered a natural expectation in theories of quantum gravity with a preferred frame.
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If spacetime is a causal set then Lorentz symmetry is unbroken
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Quantum superpositions of the speed of light

Quantum Gravity at the origin of seeds of cosmic structure?

Current approaches to the problems of dark energy and unification generically predict the existence of new fields (quintessence dilatons etc.) that will in principle couple with different strengths to different standard-model fields. These different coupling strengths will cause test materials of different compositions to fall at different rates in the same gravitational field violating the Equivalence Principle the foundation of General Relativity.

I will review the shortcomings of the standard account of the origin of anisotropies and in-homogeneities in inflationary cosmology. I will argue that something beyond the established paradigm of physics in needed for a satisfactory explanation of the process by which the seeds of structure emerge from the inflaton vacuum and will consider the application of a generalization of the ideas of R Penrose about a quantum gravity induced dynamical collapse of the quantum mechanical state of a system as a promising avenue to address the issue.