  In these lectures, I survey a number of applications of light-front methods
to hadron and nuclear physics phenomenology and dynamics, Light-front
Fock-state wavefunctions provide a frame-independent representation of hadrons
in terms of their fundamental quark and gluon degrees of freedom.
Nonperturbative methods for computing LFWFs in QCD are discussed, including
string/gauge duality which predicts the power-law fall-off at high momentum
transfer of light-front Fock-state hadronic wavefunctions with an arbitrary
number of constituents and orbital angular momentum. The AdS/CFT correspondence
has important implications for hadron phenomenology in the conformal limit,
including an all-orders derivation of counting rules for exclusive processes.
One can also compute the hadronic spectrum of near-conformal QCD assuming a
truncated AdS/CFT space. The quantum fluctuations represented by the
light-front Fock expansion leads to novel QCD phenomena such as color
transparency, intrinsic heavy quark distributions, diffractive dissociation,
and hidden-color components of nuclear wavefunctions. A new test of hidden
color in deuteron photodisintegration is proposed. The origin of leading-twist
phenomena such as the diffractive component of deep inelastic scattering,
single-spin asymmetries, nuclear shadowing and antishadowing is also discussed;
these phenomena cannot be described by light-front wavefunctions of the target
computed in isolation. Part of the anomalous NuTeV results for the weak mixing
angle could be due to the non-universality of nuclear antishadowing for charged
and neutral currents.
