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The physics anomaly no one talks about: What’s up with those neutrinos?

backreaction.blogspot.com

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Re: The physics anomaly no one talks about: What’s up with those neutrinos?

#51

Post by ncmncm »

tsimionescu wrote: post #27
ncmncm wrote: post #10

Earlier quoted context omitted.

It is rare to see two-sigma results like this reported in physics. Or did I misunderstand?

There was a 2 sigma result, that has later been confirmed by a 4.9 sigma result from a new experiment with a new detector, giving now a combined 6 sigma confidence.

The paper I asked about reports a 2 σ result.

That is distinct from the other 4.7 σ and 3.8 σ results mentioned in TFA, which combined yield a 6. AFICS nobody has suggested this one may be combined with anything.

So, my question remains open: why did a 2 σ result merit publication?

Re: The physics anomaly no one talks about: What’s up with those neutrinos?

#52

Post by user-the-name »

frutiger wrote: post #39
icegreentea2 wrote: post #29

Earlier quoted context omitted.

If you want to measure neutrinos transforming, then knowing the distance to source lets to calculate rate of transformation.

Why can't you sample at one point on the earth's surface and sample again at that point's antipode? You would know the distance that was travelled, and have measurements at both points.

Neutrinos mainly come from the sun, and the sun is massively larger than the earth. You can't draw any conclusions from measurements at two points at a distance that is much smaller than the size of the source itself.

Re: The physics anomaly no one talks about: What’s up with those neutrinos?

#53

Post by ncmncm »

hprotagonist wrote: post #47
Iolaum wrote: post #41

Earlier quoted context omitted.

Coming up with potential "tracebacks" is how theoretical physicists make papers and get citations. And then you use them to design a proper experiment that will shed light to other aspects of this anomaly. But for some reason this process ain't starting.

> But for some reason this process ain't starting. or, 2.5 years, one of which was a global pandemic, is not enough time to design, begin, and publicize a series of experiments that take a few decades to produce data in quantity to continue investigating new physics.

Again: the next step is not more experiments. The experiments are done, and confirmed the discrepancy. The next step is theorizing, which can be done in isolation, relatively unaffected by pandemic. That is what is now neglected.

After hypotheses have been shown to be plausible, i.e. account for the result correctly, yet consistent with other results, it will be time to design experiments to choose among them.

So, no, the silence is not consistent with normal process AIUI.

Re: The physics anomaly no one talks about: What’s up with those neutrinos?

#54

Post by _tom_ »

dnautics wrote: post #34
solidgol wrote: post #26

Earlier quoted context omitted.

She said 10 to the 15. 10^15

To be fair I also heard 10-15 on the first pass and then had to think about it for a second.

That's because she actually said "ten to the fifteen" not "ten to the fifteenth", so you have to decide if you autocorrect by removing the "the" -> "ten to fifteen" or by adding the "th" -> "ten to the fifteenth".

Easy to get confused.

Re: The physics anomaly no one talks about: What’s up with those neutrinos?

#55

Post by frutiger »

misnome wrote: post #43
frutiger wrote: post #39

Earlier quoted context omitted.

Why can't you sample at one point on the earth's surface and sample again at that point's antipode? You would know the distance that was travelled, and have measurements at both points.

How would you know the two different neutrinos interactions came from the same source/distance without producing them yourself?

I wouldn’t need to. By sampling hundreds of thousands of events, I would know the odds of getting a particular neutrino from a particular source is the same.

Re: The physics anomaly no one talks about: What’s up with those neutrinos?

#56

Post by akira2501 »

rpz wrote: post #14

Why do we need a particle accelerator to run experiments on neutrinos, given their apparent abundance? Is there any other way to observe neutrinos without a particle accelerator?

> given their apparent abundance?

That's part of the problem. Which Neutrinos are you measuring? The ones from your experiment, the ones from the Sun, the ones from the environment? They're exceptionally light particles, so effective shielding is difficult.

It's why a lot of these experiments are deep underground. The one I visited was in northern Minnesota in an old abandoned Mine placed half a mile under the surface and positioned in such a way to receive a neutrino beam all the way from Fermilab in Chicago.

The smaller and lighter the phenomenon, the larger your laboratory needs to be come.

https://en.wikipedia.org/wiki/MINOS

Re: The physics anomaly no one talks about: What’s up with those neutrinos?

#57

Post by misnome »

_Microft wrote: post #45
misnome wrote: post #44

Earlier quoted context omitted.

This is somewhat correct, but talking about only one class of experiment (Cherenkov detectors). Indeed it’s the child-particles of the interactions that are observed, so, electrons muons and Tau particles. Depending how you are measuring, (many approaches) these interactions are generally separable - and usually you can get some directionality out of your measured event - so you know the direction it came from. Combi…

Thanks for the reply, it is very much appreciated! I did not know that "ocean-audio based methods of detection" for neutrinos are even possible and will certainly look that up later.

I don’t know if any of them ever ended up getting off the ground, but the theory was that you could pick up the step-function shockwave from underwater interactions with a giant array of microphones. There were some test arrays in the Mediterranean IIRC, but cursory searches seem to imply that optical underwater arrays seem to have been pursued instead.

It always seemed a neat idea, that you could instrument absolutely gigantic volumes with.

Re: The physics anomaly no one talks about: What’s up with those neutrinos?

#59

Post by _Microft »

misnome wrote: post #57
_Microft wrote: post #45

Earlier quoted context omitted.

Thanks for the reply, it is very much appreciated! I did not know that "ocean-audio based methods of detection" for neutrinos are even possible and will certainly look that up later.

I don’t know if any of them ever ended up getting off the ground, but the theory was that you could pick up the step-function shockwave from underwater interactions with a giant array of microphones. There were some test arrays in the Mediterranean IIRC, but cursory searches seem to imply that optical underwater arrays seem to have been pursued instead. It always seemed a neat idea, that you could instrument absolute…

I guess the sound might be very characteristic because variations in the process of generation might be limited (amount of energy delivered / type of particle created?) and I would expect it to sound a lot like a sharp "ping" if I had to take a guess. Temperature, salinity and currents would affect propagation and dispersion but deep enough in the sea there might be a stable enough environment to be able account for that. A very interesting idea at least!

Re: The physics anomaly no one talks about: What’s up with those neutrinos?

#60

Post by maxnoe »

ncmncm wrote: post #51
tsimionescu wrote: post #27

Earlier quoted context omitted.

There was a 2 sigma result, that has later been confirmed by a 4.9 sigma result from a new experiment with a new detector, giving now a combined 6 sigma confidence.

The paper I asked about reports a 2 σ result. That is distinct from the other 4.7 σ and 3.8 σ results mentioned in TFA, which combined yield a 6. AFICS nobody has suggested this one may be combined with anything. So, my question remains open: why did a 2 σ result merit publication?

Because outcomes of (in this case even large, complex, expensive) experiments should be published independent of outcome?
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