The representation theory of de Sitter space allows for a category of partially massless particles which have no flat space analog, but could have existed during inflation. We study the couplings of these exotic particles to inflationary perturbations and determine the resulting signatures in cosmological correlators. When inflationary perturbations interact through the exchange of these fields, their correlation functions inherit scalings that cannot be mimicked by extra massive fields. We discuss in detail the squeezed limit of the tensor-scalar-scalar bispectrum, and show that certain partially massless fields can violate the tensor consistency relation of single-field inflation. We also consider the collapsed limit of the scalar trispectrum, and find that the exchange of partially massless fields enhances its magnitude, while giving no contribution to the scalar bispectrum. These characteristic signatures provide clean detection channels for partially massless fields during inflation.
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Supernova Search Team collaboration, A.G. Riess et al., Observational evidence from supernovae for an accelerating universe and a cosmological constant, Astron. J. 116 (1998) 1009 [astro-ph/9805201] [INSPIRE].
M. Spradlin, A. Strominger and A. Volovich, Les Houches lectures on de Sitter space, in Unity from duality: gravity, gauge theory and strings. Proceedings, NATO Advanced Study Institute, Euro Summer School, 76th session, Les Houches France, 30 July-31 August 2001, pg. 423 [hep-th/0110007] [INSPIRE].
V. Bargmann and E.P. Wigner, Group theoretical discussion of relativistic wave equations, Proc. Nat. Acad. Sci. 34 (1948) 211 [INSPIRE].
E.P. Wigner, On unitary representations of the inhomogeneous Lorentz group, Annals Math. 40 (1939)149 [Nucl. Phys. Proc. Suppl. B 6 (1989) 9] [INSPIRE].
T. Newton, A note on the representations of the de Sitter group, Ann. Math. 51 (1950) 730.
L. Thomas, On unitary representations of the group of de Sitter space, Ann. Math. 42 (1941) 113.
M.A. Vasiliev, Consistent equation for interacting gauge fields of all spins in (3 + 1)-dimensions, Phys. Lett. B 243 (1990) 378 [INSPIRE].
M.A. Vasiliev, More on equations of motion for interacting massless fields of all spins in (3 + 1)-dimensions, Phys. Lett. B 285 (1992) 225 [INSPIRE].
A. Higuchi, Forbidden mass range for spin-2 field theory in de Sitter space-time, Nucl. Phys. B 282 (1987) 397 [INSPIRE].
L. Bordin, P. Creminelli, A. Khmelnitsky, M. Mirbabayi and L. Senatore, Spinning cosmology, work in progress.
M. Fierz and W. Pauli, On relativistic wave equations for particles of arbitrary spin in an electromagnetic field, Proc. Roy. Soc. Lond. A 173 (1939) 211 [INSPIRE].
B. de Wit, Supergravity, in Unity from duality: gravity, gauge theory and strings. Proceedings, NATO Advanced Study Institute, Euro Summer School, 76th session, Les Houches France, 30 July-31 August 2001, pg. 1 [hep-th/0212245] [INSPIRE].
S. Weinberg, Photons and gravitons in S-matrix theory: derivation of charge conservation and equality of gravitational and inertial mass, Phys. Rev. 135 (1964) B1049 [INSPIRE].
S.R. Coleman and J. Mandula, All possible symmetries of the S-matrix, Phys. Rev. 159 (1967)1251 [INSPIRE].
S. Weinberg and E. Witten, Limits on massless particles, Phys. Lett. B 96 (1980) 59 [INSPIRE].
S. Giombi, Higher spin-CFT duality, in Proceedings, Theoretical Advanced Study Institute in Elementary Particle Physics: New Frontiers in Fields and Strings (TASI 2015), Boulder CO U.S.A., 1-26 June 2015, World Scientific, Singapore, (2017), pg. 137 [arXiv:1607.02967] [INSPIRE].
E. Sefusatti, J.R. Fergusson, X. Chen and E.P.S. Shellard, Effects and detectability of quasi-single field inflation in the large-scale structure and cosmic microwave background, JCAP 08 (2012) 033 [arXiv:1204.6318] [INSPIRE].
C. Fronsdal, Singletons and massless, integral spin fields on de Sitter space, Phys. Rev. D 20 (1979)848 [INSPIRE].
R.M. Wald, Spin-2 fields and general covariance, Phys. Rev. D 33 (1986) 3613 [INSPIRE].
N. Bartolo, A. Kehagias, M. Liguori, A. Riotto, M. Shiraishi and V. Tansella, Detecting higher spin fields through statistical anisotropy in the CMB and galaxy power spectra, Phys. Rev. D 97 (2018) 023503 [arXiv:1709.05695] [INSPIRE].
M. Shiraishi, D. Nitta, S. Yokoyama, K. Ichiki and K. Takahashi, CMB bispectrum from primordial scalar, vector and tensor non-Gaussianities, Prog. Theor. Phys. 125 (2011) 795 [arXiv:1012.1079] [INSPIRE].
J.M. Martín-García, xAct, efficient tensor computer algebra for the Wolfram language, http://www.xact.es/.
D.G. Boulware and S. Deser, Can gravitation have a finite range?, Phys. Rev. D 6 (1972) 3368 [INSPIRE].
X. Bekaert and E. Meunier, Higher spin interactions with scalar matter on constant curvature spacetimes: conserved current and cubic coupling generating functions, JHEP 11 (2010)116 [arXiv:1007.4384] [INSPIRE].
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Baumann, D., Goon, G., Lee, H. et al. Partially massless fields during inflation. J. High Energ. Phys. 2018, 140 (2018). https://doi.org/10.1007/JHEP04(2018)140