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The BICEP2 collaboration has reported a strong B mode signal in the CMBpolarization, which is well fit by a tensor-to-scalar ratio of r ~ 0.2. This isgreater than the upper limit r < 0.11 obtained from the temperatureanisotropies under the assumption of a constant scalar spectral index n_s. Thisdiscrepancy can be reduced once the statistical error and the contaminationfrom polarized dust are accounted for. If however a large value for r will beconfirmed, it will need to be reconciled with the temperature anisotropiesdata. The most advocated explanation involves a variation of n_s with scales(denoted as running) that has a magnitude significantly greater than thegeneric slow roll predictions. We instead study the possibility that the largescale temperature anisotropies are not enhanced because of a suppression of thescalar power at large scales. Such a situation can be achieved for instance bya sudden change of the speed of the inflaton (by about 14 %), and we show thatit fits the temperature anisotropies and polarization data considerably betterthan a constant running (its chi^2 improves by ~ 7.5 over that of the constantrunning, at the cost of one more parameter). We also consider the possibilitythat the large scale temperature fluctuations are suppressed by ananti-correlation between tensor and scalar modes. Unfortunately, while sucheffect does affect the temperature fluctuations at large scales, it does notaffect the temperature power spectrum and cannot, therefore, help inreconciling a large value of r with the limits from temperature fluctuations.

Suppressing the impact of a high tensor-to-scalar ratio on the temperature anisotropies