## Sunday, June 8, 2008

### Prediction: Quantum Gravity = Radiometer

A crooks radiometer is an interesting little device which, when left in the sun or in subjected to infrared heat will begin to turn. Initially it was thought to be an effect of light bouncing off the white side (causing 2x photon pressure) and being absorbed by the black (pushing back with 1x). This would cause it to spin. However, that's not enough of a force to make it actually spin and it would turn towards the black side when it properly spins towards the white.

Osborne Reynolds found that a porous plate kept hotter on one side will cause the gas to flow through the plate from cooler to the hotter side. Maxwell (father of modern physics) suggested that the edges of the radiometer can be seen as making the plates of the radiometer porous.

Another suggestion was that the hotter side would when hit with a molecule would transfer more heat and cause a bouncing effect greater than when it hit the colder side. However, the faster bouncing particles make it harder for other particles to hit that side too and this ends up with the values canceling out and the vane moving nowhere. Later, Einstein showed that the two do not actually exactly cancel exactly at the edges of the vanes (much like Maxwell's pores for Reynold's force).

Which brings us to my prediction. I predict that it will not be a stretch to explain the end result of a good theory of quantum gravity in terms of a Crooke's Radiometer.

As they both the radiometer and quantum gravity do what they shouldn't do because of a broken symmetry. What should be pressures canceling out and not exerting any force ends up not quite canceling out and things doing some very nice things. Similarly this sort of broken symmetry is found within the standard model of particle physics where the weak force only works on the left-handed quarks and leptons and not their mirror opposites. Although the laws of nature are symmetric the actual outcome of the applications of the laws doesn't always cancel out exactly (much like the edges of the vanes of a radiometer). If you put together a radiometer, it shouldn't matter which way you put the vanes because the pressures are going to cancel out. However if you put all or most of the white sides on the counterclockwise side (I've never heard that term but it should make sense) it will turn counterclockwise when subjected to some heat energies because everything doesn't actually cancel as the generally symmetric laws of physics would suggest. Similarly, without this energy it won't turn (and not just because of the second law (of thermodynamics)) but because the symmetry is perfect without the added energy.

Likewise, when you remove a lot of the energy from a substance the laws of physics suddenly change as they become superconductive and electrons don't loose their energy, magnetic fields don't work, and photons gain masses. If spacetime works like a superconductor and rather than messing up magnetic fields it messes up weak nuclear force then the laws of physics should be similar to the laws of physics we observe. Neutrons and positrons are composed of three quarks which spin around quickly (most of the mass of the particles comes from E=MC^2 as the spinning and moving particles have mass). Protons consisting of two ups and a down and neutrons consisting of one up and two down quarks (ups have a charge of +2/3 and downs -1/3, so neutrons cancel and protons get a +1). This spinning bit of quarks seems a bit like a radiometer.*

So in the end, everything interesting is interesting because it is broken. In the Crooke's radiometer we see the force of a broken symmetry (the word symmetry should be a palindrome, but then so should palindrome) making something that shouldn't spin start spinning and in particle physics things which shouldn't have mass, clump together, break apart, do what they do when they shouldn't because somehow the symmetry of particle physics is similarly broken.

A perfect universe is one that doesn't exist. Our universe is one that shouldn't. In theory, theory and practice should be the same thing... in practice they aren't.

*yes the entire paragraph was to say that they both spun and therefore "looked the same".