  We ask whether or not thermal light can be represented as a mixture of single
broadband coherent pulses. We find that it cannot. Such a mixture is simply not
rich enough to mimic thermal light; indeed, it cannot even reproduce the
first-order correlation function. We show that it is possible to construct a
modified mixture of single coherent pulses that does yield the correct
first-order correlation function at equal space points. However, as we then
demonstrate, such a mixture cannot reproduce the second-order correlation
function.
