New 2+1 dimensional nonisospectral Toda lattice hierarchy

We give a new 2+1 dimensional nonisospectral generalization of the Toda lattice hierarchy. Reductions yield a variety of new integrable hierarchies along with their underlying linear problems, including new 1+1 dimensional differential-delay hierarchies (nonisospectral and isospectral), new ordinary differential-delay hierarchies, and new discrete Painleve hierarchies. We also show that a reduction in components yields our previously obtained 2+1 dimensional nonisospectral Volterra lattice hierarchy. (c) 2007 American Institute of Physics.