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The recently proposed trans-Planckian censorship conjecture (TCC) seems torequire that the energy scale of inflation is significantly lower than thePlanck scale $(H_\text{inf}<10^{-20} \Mpl)$. This, in turn, implies that thetensor-to-scalar ratio for inflation is negligibly small, \textit{independent}of assumptions of slow-roll or even of having a single scalar field, thusruling out inflation if primordial tensor modes are ever observed. Afterdemonstrating the robustness and generality of these bounds, we show thathaving an excited initial state for cosmological perturbations seems to be away out of this problem for models of inflation.

Trans-Planckian censorship, inflation and excited initial states for perturbations