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December 11

What's the product of a collision between a neutrino and an anti-neutrino, when their combined energy is not sufficient for creating the Z boson's rest mass?

Please notice the product of that collision can't be any massless particle, i.e. neither photons nor gluons, because neutrinos only react to the weak force and to the gravitational force, whereas gravitons has never been detected so their very existence is only theoretical for the time being.

Really, I'm not sure, but I do suspect, this kind of collision between matter and antimatter will have no effect: It will be like every "regular" elastic collision between two ping pong balls. Am I right? If I am, then this "regular" collision will be an extraordinary collision between matter and antimatter, right? HOTmag (talk) 01:19, 11 December 2023 (UTC)[reply]

Does it have to be a Z boson? Can't the energy be carried off by photons, possibly with an intermediary step of the creation of a virtual electron–positron pair? --Lambiam 10:21, 11 December 2023 (UTC)[reply]

What about a collision between a neutrino and an anti-neutrino whose combined energy is not suffcient for creating the new pair you suggest? HOTmag (talk) 10:38, 11 December 2023 (UTC)[reply]

The annihilation cross section for the process suggested by Lambiam will be very small, but there is no lower energy threshold when virtual particles are involved. --Wrongfilter (talk) 10:56, 11 December 2023 (UTC)[reply]

Thank you for this clarification. By mistake, I overlooked the word "virtual" in Lambiam's response. Anyway, I still wonder if the first step after any collision between matter and antimatter may be particles that are not gauge bosons. HOTmag (talk) 11:13, 11 December 2023 (UTC)[reply]

The "first step" can instead be virtual Higgs bosons. There could also be neutrino-neutrino scattering by coupling to hypothetical particles outside the standard model, like in [1]. --Amble (talk) 18:29, 11 December 2023 (UTC)[reply]

But the Higgs particle is not a gauge boson. I still wonder if the first step after any collision between matter and antimatter may be particles that are not gauge bosons in the standard model. If the answer is negative, i.e. the first step of any collision between matter and antimatter must be gauge bosons in the standard model, then the question in the title still remains. HOTmag (talk) 08:02, 12 December 2023 (UTC)[reply]

"But the Higgs particle is not a gauge boson." Because you asked for an example that's not a gauge boson. --Amble (talk) 14:23, 13 December 2023 (UTC)[reply]

Oh, I didn't [ask for hypothetical collisions in which the first step is not a gauge boson]. I remind that you first responded to a response of mine in which I wondered whether "the first step after any collision between matter and antimatter may be particles that are not gauge bosons", i.e. whether there may be any collision between matter and antimatter [e.g. between a proton and an anti-proton or between an electron and a positron or between a neutrino and an anti-neutrino and so forth], for which [it has empirically been proved that] the first step of that collision was not gauge bosons. So you responded: "The 'first step' can instead be virtual Higgs bosons". That's why I answered you that [indeed] the Higgs particle was not a gauge boson [but it had never been empirically detected as the first step of any collision between matter and antimatter], i.e. it was not the particle I'd asked for in my response you had responded to (and I fully apologize from the bottom of my heart if it was not clear from the very beginning what I actually meant when I first wondered whether there might be a "first step" of this kind in any collision between matter and antimatter). Anyway, thank you for suggesting the Higgs boson, as a hypothetical answer [yet not an empirical one, though]. HOTmag (talk) 15:33, 13 December 2023 (UTC)[reply]

"Anyway, I still wonder if the first step after any collision between matter and antimatter may be virtual particles that are not gauge bosons." Yes, you did ask about an example that's not a gauge boson, and the answer was provided. Honestly, these threads of yours are incredibly tedious. You generally refuse to accept any answers you are given, refuse any corrections to incorrect (or at least partially incorrect) preconceptions or conditions in your stated questions, and also argue about whether answers given to you are even what you are asking about. Please, try to remember that we are all volunteers here, we aren't paid, everyone interacting with you is giving up their time to do so. With all of these various threads of yours, what is your overall intention? What are you trying to get at with these high level quantum mechanics and/or relativity questions? Maybe our knowing that would be a better place to start. --OuroborosCobra (talk) 16:01, 13 December 2023 (UTC)[reply]

"Yes, you did ask about an example that's not a gauge boson, and the answer was provided".

Only misinterpretation, probably because of the word "may" in my response to Amble (and to a previous user), which you interpreted as "may theoretically", but actually I've intended to ask Amble (and a previous user) if there may be any kind of collision between matter and antimatter (e.g. between a proton and an anti-proton or between an electron and a positron or between a neutrino and an anti-neutrino and so forth), for which it has empiraclly been proven that the first step of that collision is not a gauge boson. Actually I used the word "may", just to indicate I wondered whether any particle, which was not a gauge boson, was empirically detected as a first step in any collision between matter and antimatter: Since I referred to any collision, rather than to every collision, I found the word "may" appropriate for that purpose. Sorry for not making it clear when I used the word "may".

"Honestly, these threads of yours are incredibly tedious".

You are exempt from responding to threads you find tedious.

"You generally refuse to accept any answers you are given".

I did accept all answers that did answer my questions. This also Includes this thread.

"You...refuse any corrections to incorrect (or at least partially incorrect) preconceptions or conditions in your stated questions".

I'm pretty sure you can't quote any "incorrect (or at least partially incorrect) preconceptions or conditions" in my stated questions.

"You also argue about whether answers given to you are even what you are asking about".

I only do that when I'm sure answers given to me are not about what I intend to ask about, e.g. when those who answer me misinterpret my question (e.g when they misinterpret the word "may" I've used, and please notice I have already apologized for not clarifying - from the very beginning - what I'd really meant by that word).

"Please, try to remember that we are all volunteers here, we aren't paid, everyone interacting with you is giving up their time to do so".

I know that, and that's why I thank whoever gives up their time to interact me, including you.

"With all of these various threads of yours, what is your overall intention? What are you trying to get at with these high level quantum mechanics and/or relativity questions? Maybe our knowing that would be a better place to start".

Let's focus on the current thread (because it has nothing to do with other threads). So, I actually need the answer to the question I explictly presented in my first response to Amble (rather than my second response to them), i.e.: [Empirically speaking], must the first step of any collision between matter and anti-matter be gauge bosons? If it must, i.e. if the first step [in all experiments] of collisions between matter and antimatter was always gauge bosons, then (as indicated in the title of this thread) what's the first step [empirically received] in a collision between a neutrino and an anti-neutrino, when their combined energy is not sufficient for creating the Z boson's rest mass?

HOTmag (talk) 17:03, 13 December 2023 (UTC)[reply]

IQ Bell Curve

It has been argued that IQ follows a Gaussian bell curve, due to the central limit theorem.
However, this requires that the individual test batteries are independent of each other.
Isn't that a problem with the theory of g? 2A02:8071:60A0:92E0:FDE1:CCA5:77F9:C756 (talk) 17:19, 11 December 2023 (UTC)[reply]

I don't see the problem with g. You just need a reasonable amount of independence and a lot of them. Anyway what has happened is that the early tests poroduced a curve that matched a normal distribution pretty well - but modern tests are set up so they actually conform to a normal distribution closely and have a mean of 100 and a standard deviation of 15. They follow that curve by design. NadVolum (talk) 17:56, 11 December 2023 (UTC)[reply]

IQ scoring is intended to yield a dimensionless positive number based exactly on the Gaussian normal distribution because:

the mathematical model makes no discrmination about causes or correlations among groups of the population, avoiding controversial influences that are discussed here
by theory, if in fact individual performances on the pre-chosen tests were truly random then average IQ would be perfectly predictable for large populations
the degree to which accumulating IQ scores match the theoretical Gaussian distribution supplies a rating of the method's consistency. In practice, scores do fit the normal bell curve to a useful degree which encourages continued use of the model. However the model needs to be calibrated from field data with a standard deviation, and occasionally be completely recast to negate the observed Flynn effects of slow changes in average IQ recorded for some populations. Philvoids (talk) 02:57, 12 December 2023 (UTC)[reply]
@1 doesn't the model is designt in a way that males and females have the same average?

@2 Isn't it the case? 2A02:8071:60A0:92E0:4D2C:9077:8CBB:9452 (talk) 11:58, 12 December 2023 (UTC)[reply]

1. No because applying any gender weighting, besides being politically incorrect, would ruin IQ testing as a tool to investigate gender performance difference. Care is taken to avoid gender bias in the question design. See in the article cited for more about gender considerations.

2. No, the distribution shape of real scores cannot match exactly the model's smooth curve that has infinitely extending upper and lower tails. Philvoids (talk) 14:39, 12 December 2023 (UTC)[reply]

Modern tests are slightly tweaked in their question selection to give an equal average IQ of 100 for men and women. A different selection would favor one or the other. The standard deviation of the scores for men however is a little larger than that for women - they have more at the ends of the range. NadVolum (talk) 23:03, 12 December 2023 (UTC)[reply]