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Old Jul 9th 2019, 03:16 PM   #61
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Originally Posted by neila9876 View Post
@dragon:
It seems that you are glad to catch my flaw, haha...
In my more more humble opinion, neutron is synthetic particle (detailed see thread "strong nuclear force"), so might be neutral meson. While neutrino is the perfect neutral BASIC particle.
In my more more more humble opinion, anti photon is not necessarily itself. It's their "space - time effect" the same. Of course there might be a type of photon whose anti photon is itself. But such type of photon can only be genenrated in neutrino annihilation.
In fact I also doubt if it is correct to think it that way as above (three pigs).
haha..............
Neutrons are bayrons, made from three quarks. A meson is made from two quarks, so a neutron cannot be a meson. For example, the $\displaystyle \pi ^0$ I mentioned earlier is a meson, so I guess it wouldn't be in the same category as the neutrino.

I just had a thought. When you say that the neutrino oscillates between particle/nothing/anti-particle are you talking about a triange of states or something along a single axis? (anti-particle ..... nothing .... particle going from one end to the other and back again.)

What do you mean by "space-time effect?"

-Dan
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Old Jul 9th 2019, 05:05 PM   #62
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@dragon:
1. In respect of "space - time effect", it's not this 9876's task to talk more.haha...
2. In respect of "particle/nothing/anti-particle ", why nothing? The pig in the middle is also a real one. ( Actually, I can't understand it clearly myself, even I doubt if it's correct to think it that way.) I feel it should be depending on the specific surroundings (states of other matters). Analogy: if the tramp approachs the American captain, he looks like a sailor; if the tramp approachs the Professor woodpecker, he looks like a student; if the tramp approachs Oz93666, he looks like "Scarborough Fair".In natural environment, change should be fair, so the tramp should meet them three in turn. haha...Oh, why there is three types of leptons in nature, think it in counter way, if it's neutrino tricking...?
3. It seems a great achievement that we both think that neutrino is not in the same category as meson although we think it in different methods. We seldom did that. haha...
By the way, I heard many guys said that quarks are "in group", does it mean that nobody ever probed a single quark in experiment?

Last edited by neila9876; Jul 9th 2019 at 07:37 PM. Reason: detailed
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Old Jul 9th 2019, 07:26 PM   #63
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Originally Posted by neila9876 View Post
3. It seems a great achievement that we both think that neutrino is not in the same category as meson although we think it in different methods. We seldom did that. haha...
By the way, I heard many guys said that quarks are "in group", does it mean that nobody ever probed a single quark in experiment?
I wrote a book again. Sorry!

Well, the neutrino isn't made up of quarks and the mesons are. That's a classification scheme, not Physics so we have to be satisfied with the definitions.

In Electromagnetism charged particles interact with themselves by exchanging a photon between them. Likewise, quarks in the strong nuclear force exchange what are called gluons.

The Quantum version of Electromagnetism is a theory called Quantum ElectroDynamics, or QED. This formed the original concept behind the strong nuclear force and we call the Quantum version Quantum ChromoDynamics, or QCD. In QED we have charges, which we call + or -. In QCD things are a touch more complicated... there are three different kinds of charges here (that have nothing to do with + or -) and we label them with colors: usually green, red, and blue are used.

One of the biggest problems with QCD is something called "color confinement." We can't actually measure color... all the particles that we can observe have no color. This feature has to be put into the theories as an extra condition and this leads to all sorts of interesting stuff.

For now all we need to know is that we can't detect color in the lab. Quarks carry color charge and so do gluons. According to theory and lots and lots of experiments we have yet to find a lone quark or gluon. So we can't really do anything to see if quarks have anything rattling around inside them. (Nothing says, though, that we can't have three gluons of different colors that can be detected. This colorless combination of gluons is known as a "glu-ball." We haven't found one yet but most of us think it's just a matter of time.)

There's another effect that complicates all this: It's called "asymptotic freedom." I'm not going to go into it but it boils down that a quark deep inside the nucleus has almost no potential energy. It should then skip out of the nuclues but as it gets further from the center a force term appears and keeps the quark inside the nucleus.

-Dan
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Old Jul 11th 2019, 04:01 AM   #64
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If you want to be pedantic (which perhaps we should be)
Quarks are theoretical entities, that we cannot observe.
However they allow a mathematically consistent picture to be defined that properly models the peculiarities of the particles we can observe.

The success of this model (in matching the observed behaviours) has lead physicists to accept that it is (probably) correct.
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Old Jul 11th 2019, 04:02 PM   #65
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@dragon: Spin should be also one element that can not be detected in lab?
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Old Jul 11th 2019, 04:38 PM   #66
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@Woody:
I remember that I read a report before. It told that some physists did try to split proton in super collider. I forgot where's that report now.
What funny was that they got larger particle, just as mud ball met mud nall and became larger mud ball. haha...
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Old Jul 11th 2019, 06:53 PM   #67
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Originally Posted by neila9876 View Post
@dragon: Spin should be also one element that can not be detected in lab?
Spin is very measurable. In fact, the whole Stern-Gerlach experiment set the foundation for Quantum Mechanics. Someone once told me that SG experiment can teach you everything you need to know about basic QM.

-Dan
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Old Jul 11th 2019, 07:43 PM   #68
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@dragon:
Was that quantum number "m" dubbed as "magnetic quantum numbers" due to the Stern-Gerlach experiment ?
What "magnetic quantum numbers" means in 4D (even 5D) space is one of the subjects I want to make clear just as "spin" itself...haha

Last edited by neila9876; Jul 11th 2019 at 07:50 PM. Reason: detailed
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Old Jul 11th 2019, 08:26 PM   #69
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@dragon:
Almost all threads of this semi-tramp hint that electricity, magnetism and QM are not affairs simply in this 3D xyz Haiku space...
Why "spin" has no a corresponding physical quantity in the classical? The classical is affair in xyz Haiku space...
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Old Jul 11th 2019, 10:07 PM   #70
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Originally Posted by neila9876 View Post
@dragon:
Almost all threads of this semi-tramp hint that electricity, magnetism and QM are not affairs simply in this 3D xyz Haiku space...
Why "spin" has no a corresponding physical quantity in the classical? The classical is affair in xyz Haiku space...
"m" comes in whenever we are using spherical harmonics, as in the derivation of the electron wavefunction for a hydrogen atom. m gives a measure of the angular momentum and often ends up quantized, even Classically. Without showing you the Math I don't know what else I can say about it. As for the Stern-Gerlach, only spin is measured, not m.

Spin comes out naturally by combining QM and SR. One of the problems in the early days of QM was to find a way to incorporate spin into the Schrodinger equation. It had to be added in manually. Dirac was the first to write down an equation that includes spin automatically. Oddly enough we call this the Dirac equation and it holds for massive particles with spin 1/2. (Schrodinger's equation isn't relativistic and thus spin was missing from the formalism.)

One of the big weird things in Physcis is spin. Mathematically it is treated like an "extra" angular momentum. But it has some weird properties, the most telling of which is, for example, an electron with spin 1/2. If we were to take spin as an actual angular momentum we would find that the electron has to go around twice to make one full revolution. Clearly this is ridiculous and we so can't treat spin as an angular momentum, though the Mathematics are otherwise the same.

Why is there such a thing as spin? I have no idea. It's just a property that falls out of the Mathematics.

-Dan
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