Shang-Yi Ch’en Professor of Physics, California Institute of Technology; Founder, AQT/INQNET
Naturalness, Hierarchy And Space-Time

Naturalness, hierarchy and space-time as invoked today in physics, will be retired sooner than later.

The naturalness "strategy" and hierarchy "problem" for building models towards theories that extend the standard model of particles and their interactions (call it STh, standard theory a la David Gross) are crumbling with the measurements of the newly discovered Higgs-like boson. I call it still H-like until we have measured it exhaustively at the LHC. Nonetheless, we have built ourselves a story for what comes after the H elementary scalar that the real world does not appear to abide by.

So, the slavery of the need to be "natural", not "finely-tuned" (very subjective notions that we should have objected to, much earlier) is being lifted as we speak, and the road to high energy might be surprisingly more complex than what we were envisioning.

Towards the end of the road, and there may be none such if the road curves back at us, there is gravity or space-time that enters the mix of physics notions that are hairy and loopy and we have to upgrade them if not retire them altogether.

On related physics ideas, the notions about the particle nature of dark matter might also crumble.

Some big revolutions (and discoveries) are in store regarding fundamental notions of our quantum universe.