[graycat]

Q. So, an atom decays and gives off some particles including a neutrino. So, we look at the mass-energy arithmetic before and after the decay and see that it all adds up but does need the tiny mass-energy of a neutrino.

That fact, that small difference, seems curious, maybe toward new physics? That is, somehow maybe the mass-energy amounts are, once again in science, whole number multiples of something small. If so, then we can look for how the other particles are whole number multiples??

I have to expect that 99+% of physics students have already thought of this.

Is there anything curious about that tiny bit of mass, e.g., why it has to be there at all?

[at_a_remove]

It's a bit different than that. The decay of a neutron into a proton and an electron conserved charge, mass-energy (to an expected degree), and momentum. However, spin was not conserved. The neutrino was dreamed up as kind of a placeholder for the spin. However, it turned out that it was a real thing!

The mass-energy arithmetic should not be the thing you look at for a couple of reasons. First, it's quite difficult to measure with exactitude. Second, the binding energy for particles and their constituents plays a part that is easily within error bounds.

[graycat]

Thanks.

> First, it's quite difficult to measure with exactitude.

I wondered about something like that -- the mechanism really is exact to tiny accuracy, no fuzz, but it's super tough actually to measure that accurately, or some such. If my startup works, I'll return to physics!!! I promise!! Thanks.