  The objective of this work is to report on the influence of muon interactions
on the development of air showers initiated by astroparticles. We make a
comparative study of the different theoretical approaches to muon
bremsstrahlung and muonic pair production interactions. A detailed algorithm
that includes all the relevant characteristics of such processes has been
implemented in the AIRES air shower simulation system. We have simulated ultra
high energy showers in different conditions in order to measure the influence
of these muonic electromagnetic interactions. We have found that during the
late stages of the shower development (well beyond the shower maximum) many
global observables are significantly modified in relative terms when the
mentioned interactions are taken into account. This is most evident in the case
of the electromagnetic component of very inclined showers. On the other hand,
our simulations indicate that the studied processes do not induce significant
changes either in the position of the shower maximum or the structure of the
shower front surface.
