This is an important and interesting issue, which perhaps does not get enough love, so I was happy to see this discussion of chiral gauge theories on the lattice. There will be a followup tomorrow (update: here it is), I’d be also happy to hear about lattice supersymmetry, something I was pretty interested in a while back.
Update: For a not so recent reference on the subject, look at Martin Luscher’s lectures. More recent references, if some readers can think of any, would be appreciated.
Another update: There will be a guest post here on lattice supersymmetry in the near future, stay tuned.
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Thanks for the excellent review. Never heard about it before.
Chiral gauge theories on the lattice are trivially testable in an undergraduate chemistry lab – in one day. If spacetime is chiral then macroscopic physically and chemically identical enantiomorphs will diastereoptically embed. (If spacetime is a left foot then left and right shoes will fit with different energies.) If shoes on foot are disassembled into a common achiral state (socks), the enthalpies of transition will be different.
1) The smallest shoe construction scale is atomic. Enantiomorphic space groups P3(1)21 and P3(2)21 benzil spherical single crystals are self-similar atomic mass distributions and extremal right and left shoes. Benzil molten, in solution, gas phase, or combusted is achiral.
2) Racemic powdered benzil enthalpy of fusion, 112 J/gm at 95 C, is a fiducial standard for differential scanning calorimeter (DSC) calibration.
3) Two DSCs located between 40°-50° latitude (optimal 44.95° latitude; WGS 84) preferably between 06 October and 01 April (optimal 03 January) are abutted (locality) and positioned so that their sample pans are located along a geographic north-south line. Each holds a ~3 mm diameter ~17 mg solid single crystal sphere of benzil in a crimped carrier (against sublimation), one in space group P3(1)21 (right-handed) and one in P3(2)21 (left-handed). /_\H(fusion) for both are simultaneously run. Consistently reload sample ports and repeat every 30 minutes for 24 hours.
4) http://www.mazepath.com/uncleal/shoes.png
5) If /_\/_\H(fusion) is cyclic non-zero rather than consistent zero, spacetime is chiral in the massed sector. The vector cross product of Earth’s orbital and angular accelerations and sample orientation cycle spatial versus samples’ chiralities.
6) The best Eötvös balances are senstive to 5×10^(-14) difference/average mass/mass. A parity calorimetry experiment, on the same basis of net active mass and detectable instrument differential output, is sensitive to 3×10^(-18) mass/mass as energy/mass. Theory predicts what it is told to predict. Somebody should look.
7) Harvard, Yale, MIT, U/Wisconsin, U/Minnesota, U/Washington are in the latitude band.
Dear Uncle Al:
We are talking about a computational approach to compute properties of chiral gauge theories. The chiral lattices you are talking about, even though they can be interesting for chemical physics and as condensed matter systems, do not lead to Lorentz invariant theories like what we see at high energies in experimental physics.
My new policy is to chop anything that does not correspond, in my narrow minded view, to mainstream physics. Since David already answered, I’ll let that one stand. I’ll also preserve the links so that people who want to follow up know where to go.
I’m not even sure that comment corresponds to non mainstream physics.
But the link is interesting. I only got as far as fermion doubling before I had to go attend some or other talk about black hole information (which turned out good 😉 apologies for my noisy apple). Thanks for posting it.
Lionel, I will also chop mercilessly any chewing noises and other distractions. Order must be maintained, unlike those noisy lunchtime talks, with the apples and the non-working markers and what not.
(Glad you liked the talk, I had fun also.)