- A Flat Universe,
- A Universe with fluctuations on scales larger than light could’ve traveled across.
- A Universe whose fluctuations were adiabatic, or of equal entropy everywhere.
- A Universe where the spectrum of fluctuations were just slightly less than having a scale invariant (n_s
- And finally, a Universe with a particular spectrum of gravitational wave fluctuations.
Four of the five have been confirmed, and that's why we're way more confident in it than most people realize!
“We shall have the basic framework of the quantum theory of gravity by 2010, 2015 at the outside.”
While we’re not at all there yet, it’s still fascinating in its own right to take a look at where we actually are. In an exclusive interview, Sabine Hossenfelder gets Lee talking about the state of the field, where we’ve come, and what we have left to do.