Conformal symmetry: towards the link between the Fermi and the Planck scales.
https://www.math.columbia.edu/~woit/wordpress/?p=12584#respond Shaposhnikov has done a lot of fascinating work over the years, developing in detail a point of view which hasn’t got a lot of attention, but that seems to me very compelling. He argues that the SM and GR make a perfectly consistent theory up to the Planck scale, with the “naturalness problem” disappearing when you don’t assume something like a GUT scale with new heavy particles.
