  This master thesis seeks to understand what happens to a Quantum Field Theory
when we are in the high multiplicity regime. The motivation for this study
comes from a newly (2017) proposed mechanism that would happen in scalar
theories in this limit, the Higgsplosion. We review what is known so far about
the perturbative results in this regime and some other results coming from
different approaches. We study the consequences of this mechanism for a normal
scalar theory and if it can happen in the Standard Model. The goal is to
understand if this mechanism can really happen in usual field theory, this
question will be answered in the perturbative regime because a more general
solution is still unknown. Additionally, a new possible interpretation for the
Higgsplosion mechanism is proposed and discussed.
