Academic Journal
The cosmological bootstrap: inflationary correlators from symmetries and singularities
| العنوان: | The cosmological bootstrap: inflationary correlators from symmetries and singularities |
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| المؤلفون: | Arkani-Hamed, N., Baumann ,D., Lee, H., Leite Pimentel, Guilherme |
| المساهمون: | Arkani-Hamed, N., Baumann, D., Lee, H., Leite Pimentel, Guilherme |
| سنة النشر: | 2020 |
| المجموعة: | Scuola Normale Superiore: CINECA IRIS |
| مصطلحات موضوعية: | Cosmology of Theories beyond the SM, Effective Field Theorie, Models of Quantum Gravity, Space-Time Symmetries, Settore FIS/02 - Fisica Teorica, Modelli e Metodi Matematici |
| الوصف: | Scattering amplitudes at weak coupling are highly constrained by Lorentz invariance, locality and unitarity, and depend on model details only through coupling constants and the particle content of the theory. For example, four-particle amplitudes are analytic for contact interactions and have simple poles with appropriately positive residues for tree-level exchange. In this paper, we develop an understanding of inflationary correlators which parallels that of flat-space scattering amplitudes. Specifically, we study slow-roll inflation with weak couplings to extra massive particles, for which all correlation functions are controlled by an approximate conformal symmetry on the boundary of the spacetime. After systematically classifying all possible contact terms in de Sitter space, we derive an analytic expression for the four-point function of conformally coupled scalars mediated by the tree-level exchange of massive scalars. Conformal symmetry implies that the correlator satisfies a pair of differential equations with respect to spatial momenta, encoding bulk time evolution in purely boundary terms. The absence of unphysical singularities (and the correct normalization of physical ones) completely fixes this correlator. Moreover, a “spin-raising” operator relates it to the correlators associated with the exchange of particles with spin, while “weight-shifting” operators map it to the four-point function of massless scalars. We explain how these de Sitter four-point functions can be perturbed to obtain inflationary three-point functions. Using our formalism, we reproduce many classic results in the literature, such as the three-point function of slow-roll inflation, and provide a complete classification of all inflationary three- and four-point functions arising from weakly broken conformal symmetry. Remarkably, the inflationary bispectrum associated with the exchange of particles with arbitrary spin is completely characterized by the soft limit of the simplest scalar-exchange four-point function of conformally ... |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| Relation: | info:eu-repo/semantics/altIdentifier/wos/WOS:000529290100001; volume:2020; issue:4; journal:JOURNAL OF HIGH ENERGY PHYSICS; https://hdl.handle.net/11384/129447; info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85083667712 |
| DOI: | 10.1007/JHEP04(2020)105 |
| الاتاحة: | https://hdl.handle.net/11384/129447 https://doi.org/10.1007/JHEP04(2020)105 |
| Rights: | info:eu-repo/semantics/openAccess |
| رقم الانضمام: | edsbas.944AA7BD |
| قاعدة البيانات: | BASE |
| DOI: | 10.1007/JHEP04(2020)105 |
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