# Can a particle transform into its counter anti-particle?

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So is there a proposed theoretical mechanism for transforming a particle into its own anti-particle?

##Electron \leftrightarrow Positron##
##Proton \leftrightarrow anti-Proton##

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What do you mean by ”transform”? Without any other particles partaking in the process? In that case no, that would violate particle number.

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And charge conservation.

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What do you mean by ”transform”? Without any other particles partaking in the process? In that case no, that would violate particle number.
What I had in mind is assume we have a particle and an anti-particle and we want to switch between them.
All we need is to exchange between them is the sign of charge, is it possible?

Well don't neutral particles have zero charge and thus they are their own anti-particle?
If the answer to the above question is 'correct', then that's not what I was looking for.
Take a hydrogen atom which is neutral. If you invert the charge of both the electron and proton, you get an anti-hydrogen, which is evidently not equal to a hydrogen atom, although it is also neutral.

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Well don't neutral particles have zero charge and thus they are their own anti-particle?
If the answer to the above question is 'correct', then that's not what I was looking for.
No, this is incorrect. Neutral particles are not necessarily their own anti-particles, although it is a prerequisite for that to be the case.

Take a hydrogen atom which is neutral. If you invert the charge of both the electron and proton, you get an anti-hydrogen, which is evidently not equal to a hydrogen atom, although it is also neutral.
Well, hydrogen does not oscillate into anti-hydrogen (in the standard model) so it may be more instructive to discuss the kaons from your previous post. Neutral kaons are combinations of ##s\bar d## and ##d\bar s##.

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Well, hydrogen does not oscillate into anti-hydrogen (in the standard model) so it may be more instructive to discuss the kaons from your previous post. Neutral kaons are combinations of ##s\bar d## and ##d\bar s##.
I think that was the point. Not everything neutral is its own antiparticle.
The neutron is another example. Antineutrons are different particles.

@MathematicalPhysicist: Antiparticles differ from particles by more than just the electric charge. All quantum numbers are reversed.

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