Abstract: “In this talk, I will argue in favor of a  ‘transition amplitude’ approach to quantum gravity. For such a position to be internally consistent, not all types of symmetries are allowed. I will describe which ones are and we will see how refoliations become problematic – I will contend that they should only be recovered dynamically (as an on-shell, or effective, symmetry). Given this ‘transition amplitude’  point of view, I will further elaborate on how the allowed symmetries select a unique ‘in state’  for the amplitude. We can thereby use this ‘in state’ to produce a static wavefunction of the Universe, much like some of the interpretations of the Wheeler-DeWitt. Lastly, I will describe how one can extract our usual notion of time from such a fundamentally timeless view, at least semi-classically, through a structure called ‘semi-classical records’. Time allowing (no pun intended), I will further speculate on some recent progress in a relation between renormalization group flow and a notion of instantaneous duration (this part will be pure speculation).”

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