Even though I don’t understand the process, I do recognize that neutrinos can oscillate. In other words the three neutrino types can change into one and other, and then back again. I recognize, further, that the existence of such oscillations implies that neutrinos have a non-zero (rest) mass (and, therefore, that they travel at less than the speed of light).
Question 1: Are the differences in their masses the only difference among the neutrino types?
Question 2: As a neutrino travels (say from the Sun to the Earth) it oscillates, and hence its mass changes. Does this mean that its velocity also changes, but in a reciprocal way, in order to allow for conservation of energy?
Question 3: Is there an intuitive, non-technical way to appreciate the fact that ‘if neutrinos oscillate they must have non-zero mass’? As an example of what I mean by “an intuitive, non-technical way”, it is fairly intuitive to appreciate that if a neutrino is traveling at less than the speed of light, it’s possible that it can be its own anti-particle. This is the case since an observer could (theoretically) get in front of, or be behind, a neutrino traveling at velocities < c, with the resulting change in perspective reversing the apparent direction of its spin, i.e. changing it into its anti-particle. OTOH, if the neutrino is traveling at light speed, one can never “get in front of it” to witness the change in the direction of its spin. Ergo, it can’t be its own anti-particle. Is there any sort of “analogous analogy” to illustrate why neutrino oscillation implies non-zero neutrino mass?