Community Rules
Rule 1: Be respectful and inclusive.
Treat others with respect, and maintain a positive atmosphere.
Rule 2: No harassment, hate speech, bigotry, or trolling.
Avoid any form of harassment, hate speech, bigotry, or offensive behavior.
Rule 3: Engage in constructive discussions.
Contribute to meaningful and constructive discussions that enhance scientific understanding.
Rule 4: No AI-generated answers.
Strictly prohibit the use of AI-generated answers. Providing answers generated by AI systems is not allowed and may result in a ban.
Rule 5: Follow guidelines and moderators' instructions.
Adhere to community guidelines and comply with instructions given by moderators.
Rule 6: Use appropriate language and tone.
Communicate using suitable language and maintain a professional and respectful tone.
Rule 7: Report violations.
Report any violations of the community rules to the moderators for appropriate action.
Rule 8: Foster a continuous learning environment.
Encourage a continuous learning environment where members can share knowledge and engage in scientific discussions.
Rule 9: Source required for answers.
Provide credible sources for answers. Failure to include a source may result in the removal of the answer to ensure information reliability.
By adhering to these rules, we create a welcoming and informative environment where science-related questions receive accurate and credible answers. Thank you for your cooperation in making the Ask Science community a valuable resource for scientific knowledge.
We retain the discretion to modify the rules as we deem necessary.
In short: charge is not the only thing that defines a particle. Although the charge of the neutrinos is zero their spin differs.
A longer form of this answer is here. The answers go a bit more into detail on why "zero charge" isn't precisely correct either but I'm not sure if that goes too deep for what you're interested in!
I'm going to copy-paste the exact relevant bit here:
For each neutrino, there also exists a corresponding antiparticle, called an antineutrino, which also has no electric charge and half-integer spin. They are distinguished from the neutrinos by having opposite signs of lepton number and chirality. As of 2016, no evidence has been found for any other difference.
I knew about the chirality difference, that there are no right-handed neutrinos nor left-handed antineutrinos (or something along those lines, breaking what was thought to be a fundamental parity or symmetry), but what puzzled me was that I thought the charge difference was the one big fundamental difference between matter and antimatter, and suddenly tonight the neutrino question popped into my head. At the very least I knew that it's not a mass/negative mass type of difference.
Now as for that bit that says "opposite signs of lepton number"... I'd never even heard of this concept or characteristic, until right now.
On further thought, this is really strange.
I can visualize a negatively charged electron and a positively charged positron making contact and annihilating, how the minus and the plus cancel each other.
But what is it about neutrinos and antineutrinos that make them cancel out when they come into contact? What is it about their positive and negative characteristics that can make them go "poof!" in a burst of photons?
A visualization you could try (this obviously isn’t going to match the physical reality necessarily) is what would happen if you had two vortex phenomena (like tornadoes or whirlpools) spinning in opposite directions and they collided?
Imagine if you dug a hole in the ground. In order to dig the hole deeper, the soil needs to be piled up somewhere else. Then, imagine if you decided to move the dirt pile on top of the hole - what would happen? The soil would fill the hole, and you're left with nothing. We are simply returning to the original state of things.
That's the core idea of particles and antiparticles. At the very crux of things, there is only energy. But sometimes, the energy is able to disturb a quantum field and that produces a particle and antiparticle. The fact that the charge of the particle/antiparticle pair is opposite is not the central property of this pair. Rather, the central property that distinguishes them is more fundamental. They are fundamental opposites, and as a consequence of that fact, then they have opposite charges. They also have opposite spins for the same reason. To put it more briefly, they aren't opposite because they have different charges. They have different charges because they are opposite.
When a particle and antiparticle touch, because they are fundamentally opposites, they will cancel each other out, and the energy that went into creating them gets released.
In the way you describe it, electromagnetic charge is kinda easy to visualize. But when we get into Weak Force interactions, that's when these other, much more abstract features come into play.
For example, when you say "Spin" you don't mean regular ol' Angular Momentum, I'm guessing, but other weird types like Isospin or I-don't-know-what.
This is all fascinating stuff, truly. And way beyond my pay grade, lol!
I found that this is one of the few areas where aphantasia is a strong advantage :D
I can't help you finding better metaphors beside "it's like charge but different" as I have "accepted" the whole quantum topic as math that for some random reason can be used to make predictions which accidently correlate to our reality...
Maybe a helpful visualization is one of the precursors to quantum field theory, Dirac's sea.
The idea is that you can think of a particle as sitting on top of the surface of the "sea" while an anti particle is represented by a hole in the surface, large enough to fit one particle. When a particle encounters such a hole, it naturally drops down into it and settles there. This essentially "destroys" both the particle and the hole (the anti particle).
So essentially the opposite charge, spin, etc of a particle and anti particle are a consequence of their opposition in their fields, not the cause for the annihilation.
(Not a scientist, grains of salt and all that).
I live under the impression that we don't conclusively know, although some headway was made. There is a chance that neutrinos are their own antiparticles. I think the right term to start a search on the topic is Majorana particles. This theory was featured in Project Hail Mary by Andy Weir, BTW.
I apologise, I don't have time for a more exhaustive explnation, I would have to study it again first. If you want, I can try to have a look at it later.
If that is so, if neutrinos really are their own antiparticle, would that theoretically mean that there is no such thing as neutrino annihilation?
Like photons, which are their own antiparticle, and don't annihilate on contact with each other, but those are bosons with a completely different spin, and also have zero rest mass, unlike neutrinos/antineutrinos, which DO have mass, but seem to somehow draw it out from something other than the Higgs Field.