  Turbulence in space and astrophysical plasmas is governed by the nonlinear
interactions between counterpropagating Alfven waves. Here we present the
theoretical considerations behind the design of the first laboratory
measurement of an Alfven wave collision, the fundamental interaction underlying
Alfvenic turbulence. By interacting a relatively large-amplitude, low-frequency
Alfven wave with a counterpropagating, smaller-amplitude, higher-frequency
Alfven wave, the experiment accomplishes the secular nonlinear transfer of
energy to a propagating daughter Alfven wave. The predicted properties of the
nonlinearly generated daughter Alfven wave are outlined, providing a suite of
tests that can be used to confirm the successful measurement of the nonlinear
interaction between counterpropagating Alfven waves in the laboratory.
