Very cool! The suggestion to consider how the standard model came to be rather than starting with the result sounds like an excellent idea.
But of course i have to disagree with this: "A spin-1/2 particle is described by a spinor, which is a bit weird, but spin-1 particle is described by something more familiar: a vector!"
In my view a spinor is even more familiar than a vector: it's like a hand - it comes back to itself after 720° of rotation. Just like a vector is like an arrow or a mirror, which come back after 360°. What could be more familiar than a hand?
> it's like a hand - it comes back to itself after 720° of rotation
The analogy is a bit broken in a way that may add confusion. The hand comes back to it's starting configuration after two 360° rotations, each along a different axis. A spinor's symmetry has 720° of rotation along a single axis.
No, around a single axis. if you hold your hand palm up you can rotate in the (vertical) z axis around 360° and get a twist in the arm. another 360° undoes the twist, that's 720° around a single axis.
If you're rotating around your fingers you're doing something else, not what i mean. I'm just talking palm up, rotating in the vertical axis, 720°. like the cup dance.
Sometimes the simplest things are hidden in plain sight :) Most people point with their fingers/hands. Unlike rayman, who has vector-like hands, biological beings have them connected to their body, which makes them behave like spinors. But Dirac actually knew about this, after all there is a belt trick named after him.
Vector Meson Dominance
(johncarlosbaez.wordpress.com)
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But of course i have to disagree with this: "A spin-1/2 particle is described by a spinor, which is a bit weird, but spin-1 particle is described by something more familiar: a vector!"
In my view a spinor is even more familiar than a vector: it's like a hand - it comes back to itself after 720° of rotation. Just like a vector is like an arrow or a mirror, which come back after 360°. What could be more familiar than a hand?
> it's like a hand - it comes back to itself after 720° of rotation
The analogy is a bit broken in a way that may add confusion. The hand comes back to it's starting configuration after two 360° rotations, each along a different axis. A spinor's symmetry has 720° of rotation along a single axis.
> In my view a spinor is even more familiar than a vector
Okay... Pauli and Dirac both received Nobel Prizes for discovering spinors. Nobody needed to discover pointing in some direction.
Spinors are so intuitive that you need a 1 hour video full of animations to explain them: https://www.youtube.com/watch?v=b7OIbMCIfs4