Solid consistency

Abstract

We argue that isotropic scalar fluctuations in solid inflation are adiabatic in the super-horizon limit. During the solid phase this adiabatic mode has peculiar features: constant energy-density slices and comoving slices do not coincide, and their curvatures, parameterized respectively by ζ and R, both evolve in time. The existence of this adiabatic mode implies that Maldacena's squeezed limit consistency relation holds after angular average over the long mode. The correlation functions of a long-wavelength spherical scalar mode with several short scalar or tensor modes is fixed by the scaling behavior of the correlators of short modes, independently of the solid inflation action or dynamics of reheating.

Adiabatic media inflation

“…The quantity δσ, in the transition from inflation to radiation domination can be considered continuous. 12 The continuity of ζ is oftern taken for granted as for instance in [12] and [37]. of the scalar modes at superhorizon scales.…”

Primordial non-Gaussianity in supersolid inflation

“…It is evident that the violation of the consistency relations for solid and supersolid inflation is related both to the magnitude and the angular structure. While in solid inflation, an angular average restores the consistency relation [46], this does not happen in supersolid inflation.…”

Gaugid inflation

“…It is convenient to work in momentum space and expand in helicity eigenstates 10 9 All other quantities in the lagrangian such as the various speeds of sound and the slow-roll parameters are only weakly time dependent on the quasi-dS spacetime under consideration. 10 Given the helicity operator s ||ij ≡ ik l ε lij , the polarizations eigenstates s ij ( k) are defined by [s || , ± ] = ±2 ± . This property further implies transverse tracelessness, k i s ij = s ii = 0, and reflection hermiticity, s ( k) = s (− k).…”

“…Most of the features of single field inflation directly follow from this symmetry breaking pattern. In particular, the physics of the corresponding Goldstone boson (also known as the adiabatic mode) is governed by a robust structure [2,3] that entails conservation of the physical curvature perturbation on super-horizon scales and a set of "consistency relations" between different n-point functions that stem from the associated Ward identities [4][5][6][7][8][9][10]. Needless to say, inflationary theories characterized by the breaking pattern (2) have been explored extensively over the years -both on model-by-model basis as well as within the more model-independent, effective field theory framework [11][12][13][14].…”