Bouncing models of cosmology, as they arise e.g. in loop quantum cosmology, can generate close-to-scale-invariant fluctuation spectra as observed in the Cosmic Microwave Background (CMB). However, they are typically not Gaussian and also generate a bispectrum. It was proposed that these models can help to mitigate the large-scale anomalies of the CMB by considering large non-Gaussianities on very large scales, which decay exponentially on sub-horizon scales. It was therefore thought that this non-Gaussianity would not be visible in observations, which can only probe sub-horizon scales. In this letter we show that bouncing models with parameters such that they can mitigate the large-scale anomalies of the CMB are excluded by the Planck data with high significance of, depending on the specific model, 6.4 or 14 standard deviations.
