A model for the Pomeron at $t=0$ is suggested. It is based
on the idea of a finite sum of ladder diagrams in QCD. Accordingly,
the number of $s$-channel gluon rungs and correspondingly the powers
of logarithms in the forward scattering amplitude depends on the phase
space (energy) available, i.e. as energy increases, progressively new
prongs with additional gluon rungs in the $s$-channel open. Explicit
expressions for the total cross section involving two and three rungs
or, alternatively, three and four prongs (with $\ln^2(s)$ and
$\ln^3(s)$ as highest terms, respectively) are fitted to the
proton-proton and proton-antiproton total cross section data in the
accelerator region. Both QCD calculation and fits to the data indicate
fast convergence of the series. In the fit, two terms (a constant and a
logarithmically rising one) almost saturate the whole series, the
$\ln^2(s)$ term being small and the next one, $\ln^3(s)$, negligible.
Theoretical predictions for the photon-photon total cross section are
also given.

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