On the renormalization of ultraviolet divergences in the inflationary angular power spectrum

Spanish Relativity Meeting: almost 100 years after Einstein's revolution

Del Rio, Adrian^1 ; Navarro-Salas, Jose^1

Department of Theoretical Physics, IFIC, University of Valencia-CSIC, Faculty of Physics, Burjassot Valencia

46100, Spain^1

关键词: Analytic expressions;    Angular power spectrum;    Multipole coefficient;    Renormalization;    Scale invariance;    Space time;    Two-point function;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/600/1/012023/pdf
DOI  :  10.1088/1742-6596/600/1/012023

来源: IOP

【 摘 要 】

We revise the role of ultraviolet divergences of cosmological observables and the corresponding renormalization from a space-time perspective. We employ the two-point function of primordial perturbations generated during inflation to derive an analytic expression for the multipole coefficients Cin the Sachs-Wolfe regime. We analyzethe ultraviolet behaviorand stress the fact that the standard result in the literature is equivalent to a renormalization of the two-point function at zeroth adiabatic order. We also argue that renormalization at second adiabatic order seems to be more appropriate from a physical point of view. This may change significantly the predictions for C, while maintaining scale invariance.