Signs of Quantum Gravity in CMB Ancient Light

[marcus]

Thanks to GJ for pointing out these three links:

http://backreaction.blogspot.ca/2013/10/quantum-gravity-in-cosmic-microwave.html
Quantum Gravity in the Cosmic Microwave Background?

http://www.nature.com/news/how-to-see-quantum-gravity-in-big-bang-traces-1.13834
How to see quantum gravity in Big Bang traces

http://arxiv.org/abs/1309.5343
Using Cosmology to Establish the Quantization of Gravity
Lawrence M. Krauss, Frank Wilczek
(Submitted on 20 Sep 2013)
While many aspects of general relativity have been tested, and general principles of quantum dynamics demand its quantization, there is no direct evidence for that. It has been argued that development of detectors sensitive to individual gravitons is unlikely, and perhaps impossible. We argue here, however, that measurement of polarization of the Cosmic Microwave Background due to a long wavelength stochastic background of gravitational waves from Inflation in the Early Universe would firmly establish the quantization of gravity.
4 pages, published in Physical Review D (2014)

It was pointed out by Krauss and Wilczek back in September 2013 that seeing B-mode polarization in the CMB would amount to seeing quantum gravity.

Specialists in qg phenomenology had already absorbed that information, I remember references to it going back several years--to 2008 at least. But having folks like Krauss and Wilczek explain it with concise clear reasons made it official.

Then having Bee Hossenfelder explain their explanation in simpler language made it even clearer.

So that connection was established, so when the BICEP2 report came out Patrick day 17 March 2014 it was plain as the nose on your face :^D
We have seen quantum gravity in the swirls of ancient light and that is what it looks like.

Well…almost. Bee argues NO, which is why I put her commentary on the Krauss Wilczek paper first. See what you think.

 

[Evan Fox]

Thanks for pointing out these links GJ, it is really interesting to see how the idea of seeing quantum gravity in the CMB has progressed over the years. It's remarkable that we have been able to make such a huge leap in our understanding of the universe.