You clearly did not even read (or understand) the abstract. They mention specifically that if the theory is correct there will be a measurable result in the polarization of microwave background radiation. They elaborate further in the paper the exact characteristics they predict. I have a background in electromagnetic radiation and understand exactly what they are referring to when they talk about microwave polarization. It is not nonsensical, this is a real phenomenon. Furthermore, we are talking about foremost researchers at Princeton, Cambridge and Univ of Pennsylvania. Are you seriously suggesting that they just made up and published nonsense and submitted it for peer review? If the answer is yes then you are a lost cause. No amount of evidence will ever be enough for you.