Fermions have even more: six properties in three pairs.

1) Spin as angular moment with magnetic moment;

2) electric charge with magnetic flux around;

3) mass with gravitation curvature.

All this is known. The term ``fermions'' refers to the statistics of many-particle states.

Fermions need not carry electric or magnetic charge, that's why there's no direct relation between spin and any magnetic charge. That's, also, why the statement 2) is wrong.

Statement 3) is, also, wrong.

The situation is much simpler. A relativistic particle is defined by its mass, its spin and its charge under ``internal symmetry groups'', of which the group of U(1) rotations that describe electromagnetism is but one example.

Fermions can be neutral under internal symmetry groups; the spin-statistics theorem simply implies that, in four spacetime dimensions, fermions have spin that's a half-integer, so 1/2, 3/2 and so on.

How fermions interact with the gravitational field is, also, known and can be found in any textbook or lecture notes on general relativity, for instance https://people.sissa.it/~percacci/lectures/genrel/08-matter.pdf

Dear Chian Fan as you aware, science practice Standard model of atom theory, which still a theory, thus everything regarding atom is a theory over a theory, which means not real. In addition, to imagine these phenomenon, become unrealistic and unscientific.

regards

Dear Stam Nicolis,

fermions like electrons have no need to obey "internal symmetry groups" as you write. On the contrary, we derive these symmetry groups from observations on particles. Yesterday we knew nothing about these groups, tomorrow we will come up with something else. But in any case, we will have to answer the school questions about why there is a circular magnetic flux around a conductor with direct electric current and why physical bodies with mass cause gravitational attraction to each other.

Sometimes it can be harmful to read many textbooks.

Dear Javad Fardaei Mikhail N Dulin Stam Nicolis

Thank you for the warning. We know that physicists are shy about imagining things without much basis. However, we also know that questions, imaginations, and conjectures are one of the ways towards correct proofs and explanations.

The point of my question is not about the 2 or 3 pair property, or the symmetry group analysis. The focus of my question is on what the title says, why are so many different properties grouped together? How can they meet if they are not related to each other? Symmetric groups are one way of expressing the relationship between them, but the ultimate explanation should be physical and not stop at group theory.

Essentially it is asking what is the charge, what is the magnetic charge, what is the color charge, what is the spin, what is the mass, what is the gravitational field, and how they are related together.

We cannot assume that fermions can have no properties, nor can we assume that fermions do not produce a gravitational field.

Thanks for your attention and comments!

Best Regards, Fan

It may appear that there are many ``properties". But this is illusory. Fermions are particles, whose multiparticle states obey Fermi-Dirac statistics, that’s all.

Once more, magnetic charge, or color chargen doesn’t have anything to do with whether a particle is a fermion or not.

Any particle is a particular representation of the Poincaré group, that is defined by its mass and spin and a particular representation of some internal symmetry group, that’s completely independent of the representation of the Poincaré group.

A fermion is any representation of the Poincaré group in four spacetime dimensions, for which the spin is half-integer.

That’s all there is and this information is necessary and sufficient for understanding how such particles interact with the gravitational field and any other field.

Dear Chian Fan,

the answer on your question "why are so many different properties grouped together?" may be rather simple. Some of them or exactly three pairs I have mentioned above belong to the same single object: a discrete element of a special space named "nuclear" by me. You may read about in the reference (PDF) Toward a new physics: the physics of discrete spaces (researchgate.net) . Sorry, the text is in Spanish.

For example the particles as electron, proton and neutron are all the fermions and each of them represents a single element of "size" h in the nuclear space. Each of them has six properties in two pairs: spin and magnetic moment; charge and quantum of magnetic flux (no for neutron, it's rather a complex particle); mass and some unknown for us quantum of gravitation flux.

Our nature is very wise. The spin is needed for the particle to be always in motion, its magnetic moment is rather derivative of the spin. The charge with the magnetic flux are needed for the excitation of photons in the surrounding 3D space which I named "electromagnetic". The mass is needed to bend the surrounding space in a gravitational style.

Thank you for attention,

Dulin Mikhail.

“…All this is known. The term ``fermions'' refers to the statistics of many-particle states…”

- that isn’t essentially so. Fermions, i.e. particles that have non-integer spin, are real particles, which are as they are independently on what statistics humans invented. Though yeah, the Fermi-Dirac statistics really correctly describes what happens in many-particle structures, say, atoms,

- but fermions remain be fermions if are singled particles; and, what is the primary point - Fermi-Dirac statistics by no means explains what is “a fermion”; including what is “spin”, and in this case there are no scientific answer fundamentally – in mainstream physics at least fundamental elementary particles are point like something, and so, though particles spins are evidently some angular momentums, but point like particle evidently cannot have angular momentum since has zero radius. That

“….Fermions need not carry electric or magnetic charge, that's why there's no direct relation between spin and any magnetic charge. …”

- really so, there exist fermions that haven’t electric charge, but as an exclusion, that seems are only neutrinos. All other particles have charges and magnetic momentums that are proportional to spins. That is another thing that in some cases, say “electrically neutral” neutron really has the charge, but this charge is composed by 3 ±charges and the sum of the charges is equal to zero, however just because that neutron has the spin, its magnetic moment isn’t zero.

As well as that

“….The situation is much simpler. A relativistic particle is defined by its mass, its spin and its charge under ``internal symmetry groups'', of which the group of U(1) rotations that describe electromagnetism is but one example….”, etc.,

- is also rather questionable. The properties of any material objects, including fermions, by any means fundamentally cannot be defined by any physical theory, any theory can only describe what exists and happens in Matter, including what are fermions. At that since in mainstream physics all really fundamental phenomena/notions, first of all in this case, “Consciousness”, “Space”, “Time”, “Energy”, “Information”, and “Matter”– and so everything in Matter, i.e. “particles”, “fields”, etc., are fundamentally completely transcendent/uncertain/irrational,

- so in every case, when the mainstream develops some fundamental theory, the results completely obligatorily logically really are nothing else than some transcendent mental constructions, which are in some cases adequate to the reality only because that the theories are based on experimental data, and the fundamentally ad hoc theories’ postulates, despite that in some cases are strange, as, say, the “particle is a point” postulate above, are “adequate” – though really at applications of some also ad hoc mathematical tricks, as that is, say, in QFTs .

Really mainstream physics doesn’t know including what is “mass”, so, say, some “Higgs mechanism” is standard explanation in this case, despite that really that is too strange mental construction.

Any really fundamental question can be, and a lot of are, answered only in framework of the Shevchenko-Tokarevsky’s informational physical model, two main papers are

https://www.researchgate.net/publication/354418793_The_Informational_Conception_and_the_Base_of_Physics, and

https://www.researchgate.net/publication/355361749_The_informational_physical_model_and_fundamental_problems_in_physics

- including in the first link it is explained what are “particles”, what is a particle’s “spin”, what are two fundamentally different [inertial and gravitational] masses, what are the fundamental Nature forces and at least Gravity, Electric, and Nuclear, Forces’ charges [more see the initial models in https://www.researchgate.net/publication/365437307_The_informational_model_-_Gravity_and_Electric_Forces, and

https://www.researchgate.net/publication/369357747_The_informational_model_-Nuclear_Force.

If briefly – particles by no means are some points, that are close-loop algorithms that cyclically run as some specific cyclic disturbances in the ultimate base of Matter – the primary elementary logical structures – (at least) [4+4+1]4D binary reversible fundamental logical elements [FLE], which compose the (at least) [4+4+1]4D dense lattice, which is placed in corresponding Matter’s spacetime,

- and so particles move in the lattice/spacetime as a “FLE-flipping point”, which propagates in utmost universal kinematical” Matter’s 4D space with metrics (cτ,X,Y,Z) with 4D velocities that have identical absolute values be equal to the speed of light, c, [“bold” means 4D vector], in first approximation along some 4D “helix” that has “radius” be equal to a particle’s Compton length. The “angular momentum” of the “flipping point” for particles is equal to the Planck constant, ћ.

However really in 4D space angular momentums as vectors cannot, and so don’t, exist, and so fermions, which are created at impacts of some lattice’s FLEs by momentums that are directed along the cτ-axis, move completely in the 4D space, and when are observed – practically only what happens in physics practice - in the 3DXYZ space, the observed the 4D “angular momentum” projection on the 3D space is observed as the spin ћ/2.

Photons are created by 3D space momentums, and so their spin is observed as be equal to ћ.

Etc., more see at least the first link above. Though, of course, the “spin problem” is only one of more than 30 other fundamental problems that are solved or essentially clarified in the model, and so for real physicists it is useful, if is obligatorily, to read all the links;

- and to read SS posts in https://www.researchgate.net/post/What_is_time11#view=63c940bafa2ccd380d0b4943/6

as some introduction is useful as well.

Cheers

Wheeler said: "gravitation without gravitation, electromagnetism without electromagnetism, charge without charge, mass without mass,......"

https://www.researchgate.net/post/Is_the_electron_mass_strictly_of_electromagnetic_electrodynamic_origin