Talk:Neutrino oscillation

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Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 05:11, 17 January 2022 (UTC)

Interesting because they would be compatible...?

Regarding a particular class of beyond-SM proposals, the text stated that "These models have little predictive power and are not able to provide a cold dark matter candidate but they are considered interesting since they would be compatible with new observable signals in particle colliders." Since "they are considered interesting since they would be compatible with new observable signals in particle colliders" seems confusing and more or less meaningless, I removed it. (If it means "would be testable", then the models would have predictive power.)Harold f (talk) 16:17, 26 July 2013 (UTC)

Conservation of mass and energy

This is a request by knowledgeable non-physicists for explanation of theory. If the 3 neutrinos are of different mass, how can they interchange without violating the conservation of mass

Answer : The masses are not oscillating. This is a crucial aspect which is not very well explained in most texts. The neutrino "flavor" is nothing but a label that we assign to a neutrino by observing the accompanying lepton in any of its interactions. If a neutrino is created with a muon, it is a muon-(anti)neutrino. If a neutrino is detected with the production of an electron, it is an electron-(anti)neutrino. Oscillations are the phenomenon where this association periodically changes over time(distance). Keep in mind the interaction aspect of it, since nothing is saying what happens between these two moments, production and detection. Basic quantum mechanics tell us the particle can be in any of the allowed states, forming a superposition, while no one is observing it. And that is the whole point with the mass: although the neutrino is created in a mass-superposition, the probability of weighing a neutrino and getting a particular mass among the three possible values is a constant. We can't exactly weigh the neutrino, not without interacting with it. But if we could measure the accompanying lepton's energy with enough precision, we would be weighing the neutrino via entanglement, which is awesome!

Simulated Oscillations?

I would like WP to reject all "simulated" or "artist renditions" of scientific matters. This is biased or speculative storytelling and nothing more. --71.10.145.116 (talk) 02:06, 11 October 2015 (UTC)

@71.10.145.116: Sorry, I heartily disagree. To start with, these days, most science starts with simulations! Scientific experiment compares prediction with observation, and the prediction is usually made first because it's a lot cheaper. The design of the experiment is tweaked to give the clearest possible observation, and then a request for major funding is made.

In the case of this article, the visuals are also very useful for comprehension. They're based on parameters that are known to about 10% accuracy, so they aren't perfect representations of reality, but they're not opium dreams either. 71.41.210.146 (talk) 13:23, 15 November 2016 (UTC)

Have I got this right?

If this is correct, I'd like to add it to the article, because it was a major "aha!" moment for me.

The oscillation curves are a function of distance/energy. So you don't need lots of experiments with different baselines; if you receive neutrinos of different but known energy, then you can explore different points on the oscillation curve with a fixed baseline by varying the energy. So oscillation experiments are looking for the energy at which flavor change is maximum, which identifies the peak of the curve. As long as the baseline is known, the value may vary as much as the energy of the source neutrinos does.

I realized this while staring at the axis labels in the "Theory, graphically" charts, but perhaps an explicit statement would fit well in the "Observations" section. Or perhaps it fits best in "Propagation and interference"? 71.41.210.146 (talk) 13:35, 15 November 2016 (UTC)

Since nobody has objected (and I'm increasingly sure I have got it right), I was WP:BOLD and updated the article. It is the new second paragraph in § Observations, with a reference to § Propagation and interference. 71.41.210.146 (talk) 16:39, 21 November 2016 (UTC)

In theory, you are right. From the experimental point of view, there are limitations to your reasoning. We can't exactly tune the neutrino's energy to our will, and I can name a couple of reasons why (considering a neutrino beam): 1) Neutrino energy is a function of the decaying particle's energy, which is selected by a magnet. You have some fine-tuning but it is neither broad nor mono-energetic. 2) Producing the decaying particle, a precursor to the neutrino, requires certain kinematics conditions to be met (see en.wikipedia.org/wiki/Threshold_energy). For instance, you can't produce charged pions with protons carrying less than about 1GeV, which means your neutrinos would have about 100MeV of minimal energy. If energy has a minimum then you need longer baselines to access higher L/E.

"between -2 and -178 degrees"

@Mssgill For verification purposes, how are you pulling "between -2 and -178 degrees" out of the referenced Science paper? Rolf H Nelson (talk) 04:08, 8 May 2020 (UTC)

PMNS Matrix: U and U*

From what I have seen, the convention seems to be that

$\left|\nu _{\alpha }\right\rangle =\sum _{i}U_{\alpha i}\left|\nu _{i}\right\rangle ,$

$\left|\nu _{i}\right\rangle =\sum _{\alpha }U_{\alpha i}^{*}\left|\nu _{\alpha }\right\rangle ,$

instead of

$\left|\nu _{\alpha }\right\rangle =\sum _{i}U_{\alpha i}^{*}\left|\nu _{i}\right\rangle ,$

$\left|\nu _{i}\right\rangle =\sum _{\alpha }U_{\alpha i}\left|\nu _{\alpha }\right\rangle ,$

as it is written in this article. If someone can confirm this, please change it.

Please sign your posts. You couldn't be more wrong. Go to the PDG, equation (14.35), instead of "what you've seen". You are most probably confusing states with the quantum fields annihilating them. Cuzkatzimhut (talk) 19:32, 10 November 2020 (UTC)

Neutrino oscillation timeline

Physicist-turned-lawyer here. I'm working on an infographic, just for fun, and was hunting around for the neutrino oscillation lifetime, but couldn't find it anywhere in anything published. Then I noticed that the neutrino oscillation function on this page is given as an energy-dependent wavelength of around 1,067 km/GeV. I also noticed that this page gave some exemplary measurements of neutrino velocities relating particle energy to the measured speed deviation from c. Curious, I calculated the oscillation wavelength for each of the exemplary neutrino energies and then solved for the oscillation period in coordinate time. Then, using the Lorentz factor for each, I solved for the oscillation period in proper time (think atmospheric muon experiment)...and they all came out to the exact same time, 5.01e-12 seconds.

This seems to very strongly suggest that the neutrino oscillation has a constant period, and that period is readily ascertainable as 5.01e-12 seconds. It seems like a very, very obvious thing that ought to be noted on Neutrino, but I couldn't find it anywhere on the wiki or anywhere in anything published. I don't want to break WP:OR, though, by adding this without some sort of backing. Does anyone have any idea where I could look for confirmation of this?

Sevenperforce (talk) 20:57, 9 April 2021 (UTC)