After more than fifteen years' efforts, physicists still do not have
a consensus on the pseudogap physics in the cuprate superconductors. There
are more questions than answers. This makes high 
superconductivity
an even greater challenge.
There has recently been a growing body of evidence which supports the
relevance of precursor superconductivity, either through pairing
fluctuations or vortex fluctuations, in the underdoped (pseudogapped)
cuprates. Alternatively, new phases (e.g., antiferromagnet, insulating
state) and quantum critical physics may come into play. I will study
the evolution of the superfluid density with hole doping, the transport
properties, e.g., electric and thermal conductivities, the
superconductor-insulator transition at the lower critical doping,
vortices and the Nernst effects, as well as Andreev reflection in the
pseudogap regime. Furthermore, I am interested in the following
important question: What do the phase fluctuation and the pairing
fluctuation scenarios for the pseudogap have in common and how are they
interrelated? I shall keep my mind open to other theories while
searching for the ultimate solution for the high problem. I have
been doing well in this area, and this gives me confidence that I will
only do better in the future.