  We have studied a problem of the tachyon mediated D-brane - D-brane
annihilation from the underlying world-volume gauge field theory point of view.
The initial state was chosen in the form of two D-branes crossing at a non-zero
angle, which is non-supersymmetric configuration generically. This state was
not a groundstate of the theory and the problem at hand was a model, where we
had rather precise control over the behavior of the theory.Some applications of
this model to the D-brane physics and conclusions about stability of several
configurations were made. By taking a T-dual picture of this process on a T^2
torus, we derived known conclusion about the instability of a system consisting
of D-0 and D-2 branes, and found its decay modes.
