  The Lange-Neubert evolution equation describes the scale dependence of the
wave function of a meson built of an infinitely heavy quark and light antiquark
at light-like separations, which is the hydrogen atom problem of QCD. It has
numerous applications to the studies of B-meson decays. We show that the kernel
of this equation can be written in a remarkably compact form, as a logarithm of
the generator of special conformal transformation in the light-ray direction.
This representation allows one to study solutions of this equation in a very
simple and mathematically consistent manner. Generalizing this result, we show
that all heavy-light evolution kernels that appear in the renormalization of
higher-twist B-meson distribution amplitudes can be written in the same form.
