Attraction and repulsion for identical particles

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SUMMARY

The discussion centers on the interaction between identical particles mediated by bosons, specifically addressing the attraction and repulsion phenomena based on the spin of the exchanged bosons. It is established that bosons with even integer spin, such as spin 0, lead to attractive forces, while those with odd integer spin, like spin 1, result in repulsive forces. The conversation references the PCT Theorem and Pauli's work on the exclusion principle, highlighting the theoretical underpinnings of these interactions. The participants seek a more intuitive explanation for these complex quantum behaviors.

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  • Understanding of quantum mechanics principles
  • Familiarity with bosons and fermions
  • Knowledge of the PCT Theorem
  • Basic grasp of particle spin and its implications
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I briefly scanned back through old topics in this part of the Physics Forum, and didn't see any that seemed to bring up this exact issue, so...

I have read in several popularizations of physics that the exchange of bosons between a pair of identical particles will cause attraction if the boson has even integer spin, and repulsion if the boson has odd integer spin. Is there any sort of reasonably simple explanation?

[Example: a pair of electrons repel one another under the exchange of spin 1 (odd integer) virtual photons.]
 
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I have never seen an intuitive argument for it. The derivation usually calculates first order diagrams, then reverses Born approximation to obtain an equivalent potential. It can be seen that the potential gets a positive sign for spin 1 (generically, odd) and negative for spin 0. Thus one is repulsive, the other is attractive.
 
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Thanks, arivero.

I know that the PCT Theorem can be proved in a pretty airtight way--though it is not a very simple argument to follow. And around the start of World War II, Pauli showed in a paper (in the Physical Review, if I remember) that certain contradictions would arise if the connection between spin classes (integer vs. half-odd integer in this case) and the exclusion principle were not to hold. I was hoping something similarly elegant might be the case for the attraction vs. repulsion connection to boson spin.

Does the method you speak of work out the same way for higher order diagrams as well?
 
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