Some major open questions worthy of discussion.

Phil Anderson
Department of Physics
Princeton University.

Surprisingly, the rate at which Nature is posing us problems is greater than our ability to solve them.
  • How much of this is our fault?
  • Is our rate of generation of red herrings, and our ability to get hung up on them, greater than either?

  • The nature and extent of the strange metal.
(Note the recent confirmation of old result that the loss angle- the phase angle of the optical conductivity is constunt up to 8000 cm-1, indicating an exact power law. Recent ideas suggest a connection to the Gutzwiller projection of wavefunctions. )

  • Pseudogap. 
(In my opinion the nature of pseudogap is not an open question for meaningful discussion. Nernst phenomenology is: two coherence scales! (Andy Millis and Lev Ioffe's fat cores))

  • The "4x4" structure seen in STS. 
(Note strong 3/4 intensity suggests pairs: 4x4=(2x2) X (2x2).)

Other important areas of quantum correlated matter:

  •   Supersolids.

(Low-density case the most interesting( Na>1/2): wrong
area of FS, thermopower obeys Heikes.  A totally new phenomenology.)
  •  Capone phenomenon and Gossamer superconductivity:
(U<Uc likes superconductivity.  Are they the same in any sense?  Are they responsible for pressure-induced SC in organics? (Baskaran).)

For something entirely different: has anyone been paying attention to the relativistic
heavy ion collider physics (RHIC)?

They are busy discovering a totally unexpected strong-coupled
quantum fluid!  (low viscosity, too few jets, good hydrodynamics)