Brian Powell's latest paper: Scalar runnings

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Brian Powell's new paper, "Scalar Runnings and a Test of Slow Roll from CMB Distortions," presents intriguing challenges to current radical ideas in cosmology. The paper has garnered positive feedback, with acknowledgments for its significance and the role of Chronos in highlighting it. There is a call for intuitive explanations regarding the complex "running of running" concept discussed in the paper. Additionally, there is curiosity about potential connections between Powell's findings and recent work by Agullo, Ashtekar, and Nelson on inflation phenomenology. The discussion emphasizes the importance of understanding these concepts in the context of cosmic microwave background observations.
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Brian Powell [bapowell] has a new paper out - Scalar runnings and a test of slow roll from CMB distortions, http://arxiv.org/abs/1209.2024. This is interesting and challenges some of the more radical ideas that are currently popular. Very nice, Brian!
 
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Nice work Brian!
 
Yes! and also thank to Chronos for spotting the paper and alerting us to it. Personally I'd be glad if anyone were to offer some intuitive explanation. The "running of running" idea...there's a lot of potentially very interesting stuff here I don't adequately understand.

I'd also like to know if there is any way in which the observations described here might have a bearing on the most recent paper (re inflation phenomenology) by Agullo, Ashtekar, Nelson. Perhaps not, but it would be intriguing if so.
 
https://en.wikipedia.org/wiki/Recombination_(cosmology) Was a matter density right after the decoupling low enough to consider the vacuum as the actual vacuum, and not the medium through which the light propagates with the speed lower than ##({\epsilon_0\mu_0})^{-1/2}##? I'm asking this in context of the calculation of the observable universe radius, where the time integral of the inverse of the scale factor is multiplied by the constant speed of light ##c##.
Why was the Hubble constant assumed to be decreasing and slowing down (decelerating) the expansion rate of the Universe, while at the same time Dark Energy is presumably accelerating the expansion? And to thicken the plot. recent news from NASA indicates that the Hubble constant is now increasing. Can you clarify this enigma? Also., if the Hubble constant eventually decreases, why is there a lower limit to its value?
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