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EDIT: Completely rewritten because of the 'needs clarity' tag and some useful related questions appearing in the side-bar. I hope this is clear now

This answer gives a long list of properties of particles whose value differs by a minus sign when comparing a particle to its antiparticle. We know that anti-particles exist, so apparently for every particle there is a particle where the value of all the properties in this list are 'flipped': i.e. the same magnitude but of opposite sign.

My question is: given a particle, say an electron, does there exist a different particle where some of the properties in the list in the linked answer are flipped and some are not?

If the answer is no, why is this not possible?

If the answer is yes, what is an example of such a pair of particles?

Vincent
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    The remaining quantum number here is the lepton number. leptons are a family of 6 particle/antiparticle pairs: electron, myon and tauon, their respective neutrinos and for each the respective antiparticles. If you understand dutch, you may also understand the german wikipedia article with another nice table on leptons. – sir_khorneflakes Nov 17 '23 at 11:32
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    You don't get to choose which properties get flipped. They ALL get flipped simultaneously. – Prahar Nov 17 '23 at 14:10
  • @Prahar this was my question (see edit). Just to clarify: Do you mean 'you do not ever get to choose because these other particles do not exist', or do you mean 'if you want to call the resulting particle the anti-particle you do not get to choose because that is what the definition of the word anti-particle says'? – Vincent Nov 17 '23 at 15:02
  • Electrons and positrons are part of one of three generations of elementary fermions. Other particles in the same generation are “up” and “down quarks/antiquarks and electron neutrinos/antineutrinos. – Ghoster Nov 18 '23 at 00:20
  • @Prahar sorry, wrong, it should be Vincent. I will correct, – anna v Nov 19 '23 at 12:39
  • you have to keep in mind that elementary particles and the quantum numbers associated with them, as defined in the standard model are necessary in order to fit with the theory the data from experiments and observations, and, important, the theory has to be predictive. The standard model has succeeded up to now – anna v Nov 19 '23 at 12:43

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All charge-like quantum numbers flip upon a change of a particle to an anti-particle. In other words, charge-like quantum numbers are correlated.

It is not like that one has a distinct particle with Lepton number +1 and another one with Lepton number -1 and each has a distinct anti-particle. The particle with Lepton number -1 is the anti-particle of the particle of Lepton number +1.

This is the same for particles with non-zero Baryon number and so on.

EDIT

Actually, there exist also particles which are their own anti-particle. The most prominent one is the photon. In the standard model there exist only one photon with no partners or anti partners.

In a wider sense also triplets exist, for instance $\pi^+$, $\pi^0$ and $\pi^{-}$. They form a triplet in the vector representation of SU(2). But in a strict sense $\pi^0$ has nothing to do with $\pi^+$ and $\pi^{-}$ which are anti-particles of each other. Because the mass of $\pi^0$ has not the same mass as a $\pi^{\pm}$. In the pure viewpoint of particle-antiparticle symmetry the $\pi^0$ is not part of $\pi^{\pm}$. The $\pi^0$ is anti-particle of its own like the photon. In particular there is nothing to flip. Because the number one might want to flip is zero.

Needless to say, this applies for the standard model, i.e. the actual valid description for elementary particles which has been successfully checked in many experiments. Hypothetical theories are not considered here.

Frederic Thomas
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  • Thank you. It seems that your second sentence 'charge-like quantum numbers are correlated'. But how strong is this correlation exactly? Does any one determine all the others? I understand that going from a particle to an anti-particle you need to flip all quantum numbers, but what if I want to go from a particle to a third particle by flipping just one? Is this impossible because of this correlation? – Vincent Nov 17 '23 at 15:15
  • particles and anti-particles only appear as dublets. A third particle can only be one like a muon for instance. For a muon it is same. A muon has Lepton number 1 and the anti-muon has Lepton number -1. There are 6 Leptons and 6 quarks which are distinguished by flavour. A flavour counts as a charge-like quantum number, e.g. charmness, C=+1 for the charm quark and C=-1 for the charm anti quark. Yeah, there are also "some" composite particles like protons, neutrons & mesons which are called hadrons. – Frederic Thomas Nov 17 '23 at 15:33
  • Thank you! Maybe I will come back later with a followup question about the $\pi$'s but this will be a separate post. – Vincent Nov 17 '23 at 15:55