We quantify the degree of fine tuning required to achieve an observationally
    viable period of inflation in the strongly dissipative regime of warm
    inflation. The “fine-tuning” parameter $\lambda$ is taken to be the ratio of
    the change in the height of the potential $\Delta V$ to the change in the
    scalar field $(\Delta \phi)^{4}$, i.e. the width of the potential, and
    therefore measures the requisite degree of flatness in the potential. The best
    motivated warm inflationary scenarios involve a dissipation rate of the kind
    $\Gamma\propto T^c$ with $c\geq 0$, and for all such cases, the bounds on
    $\lambda$ are tighter than those for standard cold inflation by at least 3
    orders of magnitude. In other words, these models require an even flatter
    potential than standard inflation. On the other hand for the case of warm
    inflation with $c< 0$, we find that in a strongly dissipative regime the bound
    on $\lambda$ can significantly weaken with respect to cold inflation. Thus, if
    a warm inflation model can be constructed in a strongly dissipative, negatively
    temperature-dependent regime, it accommodates steeper potentials otherwise
    ruled out in standard inflation.

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