Understanding Spin Reversal and CPT Invariance in Physics | Explained

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Hi all,

I was just pondering why spin is odd under time reversal. I am trying to get my head around CPT invariance and am failing to find good material online.

Thanks
 
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Here, the analogy to a classical rotating object is fine: After T, it spins in the other direction, therefore the spin gets a minus sign.
 
Ah ok thanks. Turns out the analogy of hitting the rewind button on a video of the particles motion is more useful than Id thought.
 
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