Graphics: Upper Limits on the Tensor to Scalar Power Ratio
A measurement of the tensor to scalar power ratio, r, would constrain the energy scale of inflation. There is no detection at present, but recent limits on r, evaluated at a pivot scale of 0.05 Mpc-1, are shown in the following plot. This graphic is not intended to illustrate a complete history, but rather provides a snapshot of current upper limits as experiments continue to search for a detection. Please acknowledge LAMBDA when using these images.