“…6 We argue that this is indeed the case 7 by studying full nonlinear Hamiltonian for the relevant conformal and helicity-0 longitudinal modes with no spatial dependence, 4 For earlier and subsequent related works, see, e.g., [16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38], and references therein. 5 For instance, in the de Sitter case, this becomes evident from the fact that in the full nonlinear theory no enhanced local gauge symmetry (or ghost) is present for any value of the Hubble parameter, while its appearance in the perturbative framework already at the quadratic order appears to be a mere artifact of linearization [12].…”