Detalles de publicación
PP 022018
Missing large-angle correlations versus even-odd point-parity imbalance in the cosmic microwave background
(1) Instituto de Física Corpuscular (IFIC) and Departamento de Física Teórica, Centro Mixto Universitat de València-CSIC, Dr. Moliner 50, E-46100 Burjassot, Spain; (2) Department of Physics, The Applied Math Program, and Department of Astronomy, The University of Arizona, Tucson, Arizona 85721, USA; (3) IAC; (4) ULL; (5) Departamento de Matemática da Universidade de Aveiro and Centre for Research and Development in Mathematics and Applications (CIDMA), Campus de Santiago, 3810-183 Aveiro, Portugal
Context. The existence of a maximum correlation angle (θmax≳60 deg.) in the two-point angular temperature correlations of cosmic microwave background (CMB) radiation, measured by WMAP and Planck, stands in sharp contrast to the prediction of standard inflationary cosmology, in which the correlations should extend across the full sky (i.e., 180 deg.). The introduction of a hard lower cutoff (kmin) in the primordial power spectrum, however, leads naturally to the existence of θmax. Among other cosmological anomalies detected in these data, an apparent dominance of odd-over-even parity multipoles has been seen in the angular power spectrum of the CMB. This feature, however, may simply be due to observational contamination in certain regions of the sky.
Aims. In attempting to provide a more detailed assessment of whether this odd-over-even asymmetry is intrinsic to the CMB, we therefore proceed in this paper, first, to examine whether this odd-even parity imbalance also manifests itself in the angular correlation function and, second, to examine in detail the interplay between the presence of θmax and this observed anomaly.
Methods. We employed several parity statistics and recalculated the angular correlation function for different values of the cutoff kmin in order to optimize the fit to the different Planck 2018 data.
Results. We find a phenomenological connection between these features in the data, concluding that both must be considered together in order to optimize the theoretical fit to the Planck 2018 data.
Conclusions. This outcome is independent of whether the parity imbalance is intrinsic to the CMB, but if it is, the odd-over-even asymmetry would clearly point to the emergence of new physics.
Aims. In attempting to provide a more detailed assessment of whether this odd-over-even asymmetry is intrinsic to the CMB, we therefore proceed in this paper, first, to examine whether this odd-even parity imbalance also manifests itself in the angular correlation function and, second, to examine in detail the interplay between the presence of θmax and this observed anomaly.
Methods. We employed several parity statistics and recalculated the angular correlation function for different values of the cutoff kmin in order to optimize the fit to the different Planck 2018 data.
Results. We find a phenomenological connection between these features in the data, concluding that both must be considered together in order to optimize the theoretical fit to the Planck 2018 data.
Conclusions. This outcome is independent of whether the parity imbalance is intrinsic to the CMB, but if it is, the odd-over-even asymmetry would clearly point to the emergence of new physics.