If the laws of physics varied with position, each new point would need new rules but in our universe, gravity works on Mars as it does on earth. This spatial symmetry is basic to physics but neutrinos violate it because they always spin left-handed. This asymmetry is reflected neither in the world we see nor in the laws that describe it, so as Pauli said:
“I cannot believe God is a weak left hander” (Lederma & Teresi, 2012), p256.
What is spin-handedness? If you point your left thumb forward, the fingers of your hand curl in a left-handed spin, but with your right thumb forward, they curl in a right-handed spin. Figure 4.25 shows how left and right-handed screws differ, and particles also spin differently as they move.
However particles that reverse direction change their spin, so if both your hands move forward, they spin differently, but if one hand moves backwards, they spin the same. Reversing direction reverses spin, so reversing an electron’s direction should make it spin the other way, and electrons do indeed spin both ways.
By spatial symmetry, this rule should also apply to neutrinos but they all spin left, and all anti-neutrinos spin right. Electrons spin either way but their brother neutrinos don’t, and the standard model can’t explain why, or why changing the spin of a neutrino makes it an anti-neutrino. That neutrinos always spin left is a deep mystery that contradicts spatial symmetry.
Pauli couldn’t believe that God is a left-hander but what if the first event was left-handed? When the first photon made our universe matter not anti-matter, it also had to spin left or right and apparently it went left. The photons of an electron collide from opposite directions so in a physical event, it can spin either way, randomly. Changing its direction reverses both spins, so it still spins either way.
However, while an electron’s mass comes from two photon sets, a neutrino’s mass only comes from one photon set. And reversing a neutrino’s direction changes its phase, so what create its mass is now the other set of photons, which also spin left. When an electron reverses direction, the origin of its mass doesn’t change, but when a neutrino reverses direction, the other set of left-spin photons create its mass. Neutrinos then always spin left because when they reverse direction, the source of their tiny mass changes.
If anti-neutrinos are neutrino-processing in reverse, this also explains why they always spin right. Spatial symmetry requires the mirror image of a particle to be the same particle, but for a wave on a surface, this doesn’t apply. It follows that the asymmetry that made our universe matter not anti-matter is why neutrinos always spin left and anti-neutrinos always spin right.