Imagine you are in a little rowing boat, rowing round an island and you notice that your boat always gets washed towards the shore. There is no surprise, since there are likely to be more ocean waves hitting you from the open sea than from the direction of the island.
On a not entirely unrelated subject, many recent experiments (Pohl, 2010, 2016) have shown that muons (heavy electrons) in a close orbit around the proton in so-called 'muonic hydrogen' appear to be bound to the proton a more than expected, a bit like the boat is to the island. This can also be interpreted as a 'proton radius anomaly' where the proton appears to have gone on a diet, and this is what this anomaly is usually called, but an extra binding energy can just as well explain the data. Both possibilities are far too big to be explained by the standard model of physics which has no mechanism by which the proton can go on a diet or suddenly become more attractive to muons (see previous blog).
So, to cut to the chase, can Unruh radiation explain it? I have found that it can explain roughly 55% of it. If you calculate how much Unruh radiation is seen by the orbiting muon and how much of that is blocked by the central proton, just like the island blocks waves from the point of view of the boat, then this predicts that more Unruh radiation hits the muon from outside the atom than from the centre, pushing the muon closer to the proton. The predicted extra binding energy is about 55% of the observed extra binding energy. The normal proton-electron atom does not show an anomaly because an electron orbits 200 times further out than the muon and so the solid angle of the central proton is tiny and the sheltering is negligible (see the reference below for details, McCulloch, 2017).
To go further, this attraction looks a little bit like gravity, which also tends to pull matter together. Wouldn't it be funny if Fatio / Le Sage were right about gravity after all, but instead of it being due to a sheltering of electromagnetic radiation, which has been falsified, it is due to a sheltering of Unruh radiation by protons?
I recently saw an episode of Friends (The One Where Heckles Dies). It amused me because the character Phoebe declares "Gravity seems to be to be not so much pulling me down, as pushing". Maybe the writers here had something, and although Phoebe should listen to Ross about the solid evidence for evolution, her 'scientific arrogance' speech later on in the episode was brilliant: "There was a time when the greatest minds on the planet thought that the world was flat! Are you telling me that there is not the slightest chance that you might be wrong about this?". A plea for humility that is much needed in physics.
Evidence from galaxies and all other low acceleration systems shows something big and deep is rotten in the state of physics. I've managed to show that quantised inertia can clear up some of the mess. What about gravity? It has never sat well with quantum mechanics. In my recent (2016) EPL paper I managed to derive part of gravity as well as quantised inertia from the uncertainty principle. This proton radius anomaly might represent a better line of attack since, as I always prefer, there is some direct data to show the way.
Pohl, R. et al., 2010. Nature, 466, 213. http://www.nature.com/nature/journal/v466/n7303/full/nature09250.html
Pohl, R. et al., 2016. Science, 353, 6300. http://science.sciencemag.org/content/353/6300/669
McCulloch, M.E., 2017. The proton radius anomaly from the sheltering of Unruh radiation, Progress in Physics, Vol. 13, 2, 101-102. http://www.ptep-online.com/index_files/2017/PP-49-05.PDF