Spin of Particle and Antiparticle: Same or Different?

stjimmee
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So a simple question, really: Given a particle, will its antiparticle always have the same spin or not? And if not, in which cases will the spin be different?
Thanks in advance.
 
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Yes, the charge conjugation operator commutes with the spin operators, so the antiparticle always has the same spin as the particle.
 
fzero said:
Yes, the charge conjugation operator commutes with the spin operators, so the antiparticle always has the same spin as the particle.

This is not the real reason why the spins are the same. The spin, or any other quantum numbers of the antiparticle has to be the same with that of the particle, in order for them to be able to establish Lorentz invariance in the presence of conserved charges.
 
Clarification

I'm not really that far in physics (more of an applied guy--and a high school junior), so maybe this question is obvious. Does that mean that if I were to change the spin of one particle, the other would change as well?
 
No. "The spin" in the first 3 posts refers to the general property of the particle, similar to "the electric charge" or "the mass". You cannot change those (at least not in current physics).

The actual orientation of this spin can change, and it can change for each particle individually. There is no single "other particle".
 
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