The fascinating world of an electron

The fascinating world of an electron

https://reasonandscience.catsboard.com/t3157-the-fascinating-world-of-an-electron

A World of Electrons
Electrons, being so small and light may seem remote and abstract, but the world we know is primarily the world of electrons.

The light we see is emitted by electrons. Sounds we hear are carried by electrons bouncing off each other. Tastes and smells we experience are caused by chemical reactions driven by electrons. Every time we touch something we feel the repulsion of that thing’s electrons. In both plasma globes and lightning bolts, the path of electrons is visible.
Every chemical reaction is activity between electrons. Accordingly, the properties of elements, the compounds they can form, their level of reactivity, all of it, is determined by the properties of electrons.

If the mass or charge of electrons had different values, all of chemistry would change. For example, if electrons were heavier, atoms would be smaller and bonds would require more energy. If electrons were too heavy there would be no chemical bonding at all.

If electrons were much lighter, bonds would be too weak to form stable molecules like proteins and DNA. Visible and infrared light would become ionizing radiation. They would be as harmful as X-rays and UV are to us now. Our own body heat would damage our DNA.

Luckily for us, electrons weigh just enough to yield a stable, but not sterile chemistry.

Stephen Hawking in “A Brief History of Time” (1988)
The laws of science, as we know them at present, contain many fundamental numbers, like the size of the electric charge of the electron and the ratio of the masses of the proton and the electron. […]
The remarkable fact is that the values of these numbers seem to have been very finely adjusted to make possible the development of life. For example, if the electric charge of the electron had been only slightly different, stars either would have been unable to burn hydrogen and helium, or else they would not have exploded.

A Starless Universe
Electrons are very light compared to the protons and neutrons:

The proton’s mass mp is 1,836.15 times the mass of an electron me
The neutron’s mass mn is 1,838.68 times the mass of an electron me
In a ton of coal, the electrons contribute little more than half a pound.

We’ve seen how electron weight is of critical importance to chemistry. But so too are masses of other particles. It was important that:

Protons and neutrons be close in weight: mp ≈ mn
Yet differ in mass by more than one electron: |mp − mn| > me
And also that neutrons be heavier than protons: mn > mp
As it happens, all three of these conditions hold true. Had any of them not been met we end up with a universe devoid of life.
https://alwaysasking.com/is-the-universe-fine-tuned/


CALUM MILLER Defence of the fine-tuning argument JULY 25, 2017
Bohr’s Quantization Rule
Danish physicist Niels Bohr proposed this at the beginning of the 20th century, suggesting that electrons can only occupy discrete orbitals around atoms. If this were not the case, then electrons would gradually reduce their energy (by radiation) and eventually (though very rapidly) lose their orbits. This would preclude atomic stability and chemical complexity, and so also preclude the existence of EMAs.

The Pauli Exclusion Principle
Princeton physicist Freeman Dyson has pointed out (1979, p. 251), if the Pauli exclusion principle did not exist—which is what keeps two electrons from occupying the same energy state in an atom—all electrons would occupy the lowest atomic energy state, and thus no complex atoms could exist. Thus, if any of these fundamental laws or principles were missing, the existence of complex, intelligent life would probably be rendered impossible.

This principle, formalized in 1925 by Austrian physicist Wolfgang Pauli, says that no two particles with half-integer spin (fermions) can occupy the same quantum state at the same time. Since each orbital has only two possible quantum states, this implies that only two electrons can occupy each orbital. This prevents electrons from all occupying the lowest atomic orbital, and so facilitates complex chemistry
https://calumsblog.com/2017/07/25/full-defence-of-the-fine-tuning-argument-part-4/

If electrons were bosons, rather than fermions, then they would not obey the Pauli exclusion principle. There would be no chemistry. It implies that not more than two electrons can occupy the same orbital in an atom, since a single orbital consists of two possible quantum states corresponding to the spin pointing in one direction and the spin pointing in the opposite direction. This allows for complex chemistry since, without this principle, all electrons would occupy the lowest atomic orbital. Thus, without this principle, no complex life would be possible.

R. P. Feynman wrote of the Pauli exclusion principle, “In fact, almost all the peculiarities of the material world hinge on this wonderful fact.” Measurements show no violation and confirm the generalized Pauli exclusion principle with an error of one part in one quintillion.
https://www.nature.com/articles/s42005-019-0110-3

S. Hossenfelder (2020): The Pauli exclusion principle is a law of nature; it's just how the world is.
https://www.frontiersin.org/articles/10.3389/fphy.2020.00139/full

Ethan Siegel This Little-Known Quantum Rule Makes Our Existence Possible May 28, 2019
If we didn’t have the Pauli Exclusion Principle to prevent multiple fermions from having the same quantum state, our Universe would be extremely different. Every atom would have almost identical properties to hydrogen, making the possible structures we could form extremely simplistic. White dwarf stars and neutron stars, held up in our Universe by the degeneracy pressure provided by the Pauli Exclusion Principle, would collapse into black holes. And, most horrifically, carbon-based organic compounds — the building blocks of all life as we know it — would be an impossibility for us.

Take a look around you at everything on Earth. If you were to investigate what any object is made out of, you could subdivide it into progressively smaller and smaller chunks. All living creatures are made up of cells, which in turn are composed of a complex array of molecules, which themselves are stitched together out of atoms. Atoms themselves can be broken down further: into atomic nuclei and electrons. These are the constituent components of all matter on Earth and, for that matter, all the normal matter we know of in the Universe. It might make you wonder how this occurs. How do atoms, made of atomic nuclei and electrons, which come in less than 100 varieties, give rise to the enormous diversity of molecules, objects, creatures, and everything else we find? We owe the answer to one underappreciated quantum rule: the Pauli Exclusion Principle.


The atomic orbitals in their ground state (top left), along with the next-lowest energy states as you progress rightwards and then down. These fundamental configurations govern how atoms behave and exert inter-atomic forces.

When most of us think of quantum mechanics, we think of the bizarre and counterintuitive features of our Universe on the smallest scales. We think about Heisenberg's uncertainty and the fact that it's impossible to simultaneously know pairs of physical properties (like position and momentum, energy and time, or angular momentum in two perpendicular directions) beyond a limited mutual precision.

We think about the wave-particle nature of matter, and how even single particles (like electrons or photons) can behave as though they interfere with themselves. And we often think about Schrödinger's cat, and how quantum systems can exist in a combination of multiple possible outcomes simultaneously, only to reduce to one specific outcome when we make a critical, decisive measurement.


Schrodinger's cat is a thought experiment designed to illustrate the bizarre and counterintuitive nature of quantum mechanics. A quantum system can be in a superposition of multiple states until a critical measurement/observation is made, at which point there is only one measurable outcome.

Most of us barely give a second thought to the Pauli Exclusion Principle, which simply states that no two identical fermions can occupy the same exact quantum state in the same system.

Big deal, right?

Actually, it's not only a big deal; it's the biggest deal of all. When Niels Bohr first put out his model of the atom, it was simple but extremely effective. By viewing the electrons as planet-like entities that orbited the nucleus, but only at explicit energy levels that were governed by straightforward mathematical rules, his model reproduced the coarse structure of matter. As electrons transitioned between the energy levels, they emitted or absorbed photons, which in turn described the spectrum of each individual element.


When free electrons recombine with hydrogen nuclei, the electrons cascade down the energy levels, emitting photons as they go. In order for stable, neutral atoms to form in the early Universe, they have to reach the ground state without producing a potentially ionizing, ultraviolet photon. The Bohr model of the atom provides the course (or rough, or gross) structure of the energy levels, but this already was insufficient to describe what had been seen decades prior.

If it weren't for the Pauli Exclusion Principle, the matter we have in our Universe would behave in an extraordinarily different fashion. The electrons, you see, are examples of fermions. Every electron is fundamentally identical to every other electron in the Universe, with the same charge, mass, lepton number, lepton family number, and intrinsic angular momentum (or spin).

If there were no Pauli Exclusion Principle, there would be no limit to the number of electrons that could fill the ground (lowest-energy) state of an atom. Over time, and at cool enough temperatures, that's the state that every single electron in the Universe would eventually sink to. The lowest energy orbital — the 1s orbital in each atom — would be the only orbital to contain electrons, and it would contain the electrons inherent to every atom.


This artist's illustration shows an electron orbiting an atomic nucleus, where the electron is a fundamental particle but the nucleus can be broken up into still smaller, more fundamental constituents.

Of course, this is not the way our Universe works, and that's an extremely good thing. The Pauli Exclusion Principle is exactly what prevents this from occurring by that simple rule: you cannot put more than one identical fermion in the same quantum state.

Sure, the first electron can slide into the lowest-energy state: the 1s orbital. If you take a second electron and try to put it in there, however, it cannot have the same quantum numbers as the previous electron. Electrons, in addition to the quantum properties inherent to themselves (like mass, charge, lepton number, etc.) also have quantum properties that are specific to the bound state they're in. When they're bound to an atomic nucleus, that includes energy level, angular momentum, magnetic quantum number, and spin quantum number.


The electron energy states for the lowest possible energy configuration of a neutral oxygen atom. Because electrons are fermions, not bosons, they cannot all exist in the ground (1s) state, even at arbitrarily low temperatures. This is the physics that prevents any two fermions from occupying the same quantum state, and holds most objects up against gravitational collapse.

The lowest-energy electron in an atom will occupy the lowest (n = 1) energy level, and will have no angular momentum (l = 0) and therefore a magnetic quantum number of 0 as well. The electron's spin, though, offers a second possibility. Every electron has a spin of ½, and so will the electron in the lowest-energy (1s) state in an atom.

When you add a second electron, it can have the same spin but be oriented in the opposite direction, for an effective spin of -½. This way, you can fit two electrons into the 1s orbital. After that, it's full, and you have to go to the next energy level (n = 2) to start adding a third electron. The 2s orbital (where l = 0, also) can hold an additional two electrons, and then you have to go to the 2p orbital, where l = 1 and you can have three magnetic quantum numbers: -1, 0, or +1, and each of those can hold electrons with spin of +½ or -½.


The each s orbital (red), each of the p orbitals (yellow), the d orbitals (blue) and the f orbitals (green) can contain only two electrons apiece: one spin up and one spin down in each one.

The Pauli Exclusion Principle — and the fact that we have the quantum numbers that we do in the Universe — is what gives each individual atom their own unique structure. As we add greater numbers of electrons to our atoms, we have to go to higher energy levels, greater angular momenta, and increasingly more complex orbitals to find homes for all of them. The energy levels work as follows:

The lowest (n = 1) energy level has an s-orbital only, as it has no angular momentum (l = 0) and can hold just two (spin +½ and -½) electrons.
The second (n = 2) energy level has s-orbitals and p-orbitals, as it can have an angular momentum of 0 (l = 0) or 1 (l = 1), which means you can have the 2s orbital (where you have spin +½ and -½ electrons) holding two electrons and the 2p orbital (with magnetic numbers -1, 0, and +1, each of which holds spin +½ and -½ electrons) holding six electrons.
The third (n = 3) energy level has s, p, and d-orbitals, where the d-orbital has an angular momentum of 2 (l = 2), and therefore can have five possibilities for magnetic numbers (-2, -1, 0, +1, +2), and can therefore hold a total of ten electrons, in addition to the 3s (which holds two electrons) and 3p (which holds six electrons) orbitals.


The energy levels and electron wavefunctions that correspond to different states within a hydrogen atom, although the configurations are extremely similar for all atoms. The energy levels are quantized in multiples of Planck's constant, but the sizes of the orbitals and atoms are determined by the ground-state energy and the electron's mass. Additional effects may be subtle, but shift the energy levels in measurable, quantifiable fashions.

Each individual atom on the periodic table, under this vital quantum rule, will have a different electron configuration than every other element. Because it's the properties of the electrons in the outermost shells that determine the physical and chemical properties of the element it's a part of, each individual atom has its own unique sets of atomic, ionic, and molecular bonds that it's capable of forming.

No two elements, no matter how similar, will be the same in terms of the structures they form. This is the root of why we have so many possibilities for how many different types of molecules and complex structures that we can form with just a few simple raw ingredients. Each new electron that we add has to have different quantum numbers than all the electrons before it, which alters how that atom will interact with everything else.


The way that atoms link up to form molecules, including organic molecules and biological processes, is only possible because of the Pauli exclusion rule that governs electrons.

The net result is that each individual atom offers a myriad of possibilities when combining with any other atom to form a chemical or biological compound. There is no limit to the possible combinations that atoms can come together in; while certain configurations are certainly more energetically favorable than others, a variety of energy conditions exist in nature, paving the way to form compounds that even the cleverest of humans would have difficulty imagining.

But the only reason that atoms behave this way, and that there are so many wondrous compounds that we can form by combining them, is that we cannot put an arbitrary number of electrons into the same quantum state. Electrons are fermions, and Pauli's underappreciated quantum rule prevents any two identical fermions from having the same exact quantum numbers.


A white dwarf, a neutron star or even a strange quark star are all still made of fermions. The Pauli degeneracy pressure helps hold up all stellar remnants against gravitational collapse, preventing a black hole from forming.

If we didn't have the Pauli Exclusion Principle to prevent multiple fermions from having the same quantum state, our Universe would be extremely different. Every atom would have almost identical properties to hydrogen, making the possible structures we could form extremely simplistic. White dwarf stars and neutron stars, held up in our Universe by the degeneracy pressure provided by the Pauli Exclusion Principle, would collapse into black holes. And, most horrifically, carbon-based organic compounds — the building blocks of all life as we know it — would be an impossibility for us.

The Pauli Exclusion Principle isn't the first thing we think of when we think of the quantum rules that govern reality, but it should be. Without quantum uncertainty or wave-particle duality, our Universe would be different, but life could still exist. Without Pauli's vital rule, however, hydrogen-like bonds would be as complex as it could get.

Leonard Susskind The Cosmic Landscape: String Theory and the Illusion of Intelligent Design 2006
If all the standard particles existed with the right mass and the right forces, chemistry could still fail. One thing more is needed: electrons must be fermions. The fact that fermions are so exclusive—you can’t put more than one in a quantum state—is essential to chemistry. Without the Pauli exclusion principle, all electrons in an atom would sink down to the lowest atomic orbits, where they would be much more difficult to dislodge. Ordinary chemistry is completely dependent on the Pauli principle. If electrons suddenly turned into the more sociable bosons, life-based on carbon chemistry would go poof. So you see that a world with ordinary chemistry is far from generic.
https://3lib.net/book/2472017/1d5be1

John Blamire: The Nature of ...... electrons and energy 2003
When an electron is hit by a photon of light, it absorbs the quanta of energy the photon was carrying and moves to a higher energy state.
One way of thinking about this higher energy state is to imagine that the electron is now moving faster, (it has just been "hit" by a rapidly moving photon). But if the velocity of the electron is now greater, it's wavelength must also have changed, so it can no long stay in the original orbital where the original wavelength was perfect for that orbital-shape. So the electron moves to a different orbital where once again its own wavelength is in phase with its self. Electrons therefore have to jump around within the atom as they either gain or lose energy. This property of electrons, and the energy they absorb or give off, can be put to an every day use. Almost any electronic device you buy these days comes with one or more Light Emitting Diodes (usually called "LEDs"). These are tiny bubbles of epoxy or plastic with two wire connectors. When electricity is passed through the diode it glows with a characteristic color telling you that the device is working, switched on and ready to do it's work. Deep in the semiconductor materials of the LED are "impurities", materials such as aluminum, gallium, indium and phosphide. When properly stimulated, electrons in these materials move from a lower level of energy up to a higher level of energy and occupy a different orbital. Then, at some point, these higher energy electrons give up their "extra" energy in the form of a photon of light, and fall back down to their original energy level. The light that has suddenly been produced rushes away from the electron, atom and the LED to color our world. Typically, the light produced by a LED is only one color (red or green being strong favorites). Although they are cheap, easy to make, don't cost a lot to run, LEDs are not usually used to light a room, because they cannot normally produce the wide range of different colors needed in "white" light.
http://www.brooklyn.cuny.edu/bc/ahp/LAD/C3/C3_elecEnergy.html




David Tong: Applications of Quantum Mechanics 2017
http://www.damtp.cam.ac.uk/user/tong/aqm/aqm.pdf

UNCOMMON DESCENT Should We Call The Pauli Exclusion Principle Quantum Fine-Tuning? May 29, 2019
https://uncommondescent.com/intelligent-design/should-we-call-the-paul-exclusion-principle-quantum-fine-tuning/

4. Electric Charge


1. If you throw the electric charges and quarks together at random, you get no atoms and a dead universe.
2. So in fact, the electric charges and quarks were was not thrown together at random, but selected carefully to permit stable atoms, and a life-permitting universe. 
3. Of course, we can appeal to physics that we don't even know, and posit a multiverse, and that random shuffling of these fundamental constants did permit that one emerged permitting a functional outcome, but that would just be a multiverse of the gaps argument.
4. The best explanation is that an intelligent designer created the right constants, fundamental forces, charges, colors etc. that produced stable atoms, and a life-permitting universe for his own purposes.  

A World of Electrons
Electrons, being so small and light may seem remote and abstract, but the world we know is primarily the world of electrons.

The light we see is emitted by electrons. Sounds we hear are carried by electrons bouncing off each other. Tastes and smells we experience are caused by chemical reactions driven by electrons. Every time we touch something we feel the repulsion of that thing’s electrons. In both plasma globes and lightning bolts, the path of electrons is visible.
Every chemical reaction is activity between electrons. Accordingly, the properties of elements, the compounds they can form, their level of reactivity, all of it, is determined by the properties of electrons.

If the mass or charge of electrons had different values, all of chemistry would change. For example, if electrons were heavier, atoms would be smaller and bonds would require more energy. If electrons were too heavy there would be no chemical bonding at all.

If electrons were much lighter, bonds would be too weak to form stable molecules like proteins and DNA. Visible and infrared light would become ionizing radiation. They would be as harmful as X-rays and UV are to us now. Our own body heat would damage our DNA.

Luckily for us, electrons weigh just enough to yield a stable, but not sterile chemistry.

Stephen Hawking in “A Brief History of Time” (1988)
The laws of science, as we know them at present, contain many fundamental numbers, like the size of the electric charge of the electron and the ratio of the masses of the proton and the electron. […]
The remarkable fact is that the values of these numbers seem to have been very finely adjusted to make possible the development of life. For example, if the electric charge of the electron had been only slightly different, stars either would have been unable to burn hydrogen and helium, or else they would not have exploded.

A Starless Universe
Electrons are very light compared to the protons and neutrons:

The proton’s mass mp is 1,836.15 times the mass of an electron me
The neutron’s mass mn is 1,838.68 times the mass of an electron me
In a ton of coal, the electrons contribute little more than half a pound.

We’ve seen how electron weight is of critical importance to chemistry. But so too are masses of other particles. It was important that:

Protons and neutrons be close in weight: mp ≈ mn
Yet differ in mass by more than one electron: |mp − mn| > me
And also that neutrons be heavier than protons: mn > mp
As it happens, all three of these conditions hold true. Had any of them not been met we end up with a universe devoid of life.
https://alwaysasking.com/is-the-universe-fine-tuned/




Sergey Shevchenko Institute of Physics of the National Academy of Science of Ukraine
“…"Charge" is a POSTULATE used to explain some experimental observations…”
- that is, of course, so, though that completely relates to
“….. So, the characteristics of "charge" derive from the experiments that went into Maxwell's (and similar) sets of equations….”
also: Maxwell equations are also ad hoc postulates that are derived from experiments of Ampere, Faraday, etc., aimed at to fit the theory with experiment.
As that is in all physics – every theory eventually is fitting of some mathematical constructions with experimental data, in any physical theory the Meta-physical phenomena/notions/objects not only “charge”, but also, say, “a particle”, “mass”, “Energy”, etc. are only ad hoc non-explainable mathematical values.
Again – see the SS post above, these phenomena can be, and are, clarified only in the SS&VT “The Information as Absolute” conception [the link see the post], where it is rigorously proven that everything is some informational patterns/systems of the patterns.
So, including “charge” is nothing else than some informational logical construction that exchange by information with other logical constructions in accordance with the basal set of laws/links/constants on which the whole information system “Matter” is organized, and changes/evolves.
So now there is no Meta-physical problems, the problems are purely technique – how correctly decode/translate onto human’s language some informational constructions that “are written” on some unknown for humans language; i.e. physics principally doesn’t differ from, say, a case when some Egyptologist decode some wording on some antic Egypt sarcophagus.
The next important inference that follows from the conception is in that so there is nothing surprising when some humans correctly decode information in Matter, and, since the Matter’s basal set above provides – and had provided, resulting in a huge diversity of material objects and systems of the objects, which are based on some next levels sets of laws/links/constants, to decode these laws/links/constants having practically no understanding about what the utmost fundamental and universal Matter’s basal set is – just that is the number of the physical theories that are adequate to the objective reality.
https://www.researchgate.net/post/Where-do-electrons-and-protons-get-their-charge-from

Leonard Susskind The Cosmic Landscape: String Theory and the Illusion of Intelligent Design 2006
The quark masses vary over a huge range from roughly 10 electron masses for the up-and down-quarks to 344,000 electron masses for the top-quark. Physicists puzzled for some time about why the top-quark is so heavy, but recently we have come to understand that it’s not the top-quark that is abnormal: it’s the up-and-down-quarks that are absurdly light. The fact that they are roughly twenty thousand times lighter than particles like the Z-boson and the W-boson is what needs an explanation. The Standard Model has not provided one. Thus, we can ask what the world would be like if the up-and-down quarks were much heavier than they are. Once again—disaster! Protons and neutrons are made of up-and down-quarks. According to the quark theory of protons and neutrons, the nuclear force (force between nucleons) can be traced to quarks hopping back and forth between these nucleons. If the quarks were much heavier, it would be much more difficult to exchange them, and the nuclear force would practically disappear. With no sticky flypaper force holding the nucleus together, there could be no chemistry. Luck is with us again.
https://3lib.net/book/2472017/1d5be1

Anjan Sadhukhan QUANTIZED CHARGE & FRACTIONAL CHARGE: FEW FACTS, FINDINGS AND NEW IDEAS  June 3, 2020
The physical world around us is made up of different atoms and molecules which are the building blocks of the Universe. Molecules are the collection of atoms and atoms are consisting of neutral neutrons, negatively charged electrons, and an equal number of positively charged protons. Atoms are effectively charged neutral. However, any system possessing an unequal number of electrons and protons is referred to as the ionic system. 

What is charge?
The charge on the electron is a fundamental constant of nature.
https://openstax.org/books/physics/pages/18-1-electrical-charges-conservation-of-charge-and-transfer-of-charge

It is one of the most fundamental questions of nature. Like mass, charge is also a physical property. If we place an object in the gravitational field, due to “mass” it will experience force. In the same way, a charged particle experiences force in the electromagnetic field due to the presence of “charge” in it.  It’s well accepted that e is the smallest available independent charge in the physical world. However, the composite particles like neutrons and protons are made up of some elementary particles called ‘quarks’ having smaller charges, multiple of e/3.
https://adamasuniversity.ac.in/quantized-charge-fractional-charge-few-facts-findings-and-new-ideas/

It's as if an electron says: hey quarks, let's team up, let's make an atom. Quarks: Hey, great idea, how much electric charge do you have? (Let's call it e). OK so we will team up of three of us, so we will just take each of us -1/3 or 2/3 of your charge. Electron says: Great!, I feel it, this way we can have a stable atom. Quarks: Great! ( Or maybe it was rather their creator thinking about that, in order to make, in the end, you and me ?! ) It seems that the quarks teamed up exactly so three of them can cancel out (attract) exactly the electron's electric charge. Now, here is the thing:  More elaborate composite nucleon models can have constituent partons with other rational multiples, and eventually not cancel out with the charge of the electron, and there would be no stable atoms, but ions, and no molecules, and life in the universe !! Composite particles could result in fractional charges. For example, 2 quarks and one anti-quark could sum up and result in a fractional charge ( 1/3).

So is this state of affairs coincidence, or the result of the thoughts of our wise creator?

Q & A: Quarks and Fractional Charges  12/28/2009
Protons have charge +1, and electrons, -1, using units of e. The charge of an atom or composite particle is found by adding the charges of its protons and electrons (since neutrons are electrically neutral). Therefore, the charges of such particles are integer values. However, there are subatomic particles with fractional charges. It turns out that protons and neutrons are composed of particles called "quarks." These quarks, which come in different "flavors" (up, down, charm, strange, top, bottom) make up certain particles. They have fractional charge. Up, charm, and top all have fractional charge of +2/3, while down, strange, and bottom all have a charge of -1/3. Protons are composed of two up quarks and one down quark, so the total charge is +1. Likewise, neutrons are composed of two down quarks and one up quark, so the total charge is 0. Quarks are confined to the particles they compose. This is, appropriately, referred to as "confinement." This is why we don't observe quarks--and therefore their fractional charges--outside their composite particles (such as protons and neutrons).
https://van.physics.illinois.edu/qa/listing.php?id=15151&t=quarks-and-fractional-charges

Quarks have a real fraction of the elementary charge (-1/3 or 2/3). Baryons are made up of three quarks, and that those quarks can have -1/3 or 2/3 the elementary charge. This way, the quarks can combine so that the Baryon will have an integer of the elementary charge. This way, the nucleus, and the electron can be in a stable atomic state, where their electric charges cancel (attract) exactly. Any other way, the atom would not be stable.

In reality, the charge of the electron is not an integer, it is  1.6021765 × 10−19 coulomb, or 4.80320451 × 10−10 electrostatic unit (esu, or statcoulomb).  Any amount of charge is nothing but the integer multiple of small units of charge, called the elementary charge, e, which is equal to  Coulomb (SI unit of charge). The interaction between charged objects is a non-contact force that acts over some distance of separation. 
https://www.physicsclassroom.com/class/estatics/Lesson-3/Coulomb-s-Law

In particle physics and physical cosmology, Planck units are a set of units of measurement defined exclusively in terms of four universal physical constants, in such a manner that these physical constants take on the numerical value of 1 when expressed in terms of these units.
https://en.wikipedia.org/wiki/Planck_units

The electromagnetic force is the Coulomb interaction.  This is the familiar law that says that like charges repel each and opposites attract.  This law alone dominates the interactions between essentially all objects larger than an atomic nucleus (10−15 meters) and smaller than a planet (10^7 meters).
https://www.ribbonfarm.com/2015/06/23/where-do-electric-forces-come-from/

Where do quarks get their charge?
Science has no answer to why nature uses certain fundamental rules and physical laws and not some other rules that we can conceive. That is probably a question best left to priests or philosophers.  For example, the electric charge is an intrinsic property of charged particles and it comes in 2 flavors: positive and negative. Even scientists don’t know where it comes from; it’s something that’s observed and measured. It gets worse: nobody knows how let alone why opposite charges attract and similar charges repel according to Coulomb’s law.

Those are the basic rules of Nature that we discovered. We don’t know why these are the rules. And unless we find a more fundamental rule from which these rules are deduced, we will never know the answer to that why question (and even then, we’d just replace one why with another.)

Bill C. Riemers Ph.D. Experimental High Energy Physics, Purdue University July 17, 2016
The smallest observable NET charge for a charged set of quarks is 1. But the quarks that make up the group have a fractional charge. This is far more of a complex result than anyone would have ever reasonably expected. But it is 100% consistent experimental observations. My best answer as to why quarks have a fraction charge is if there is a GOD, then GOD is both extremely clever and GOD has a really twisted sense of humor (as this seems like an Easter Egg in the laws of physics.) God also seems to appreciate the beauty of higher mathematics.
[url=https://www.quora.com/Where-do-quarks-get-their-charge#:~:text=In general particles either have,make the baryons and mesons][/url][url][url=https://www.quora.com/Where-do-quarks-get-their-charge#:~:text=In general particles either have,make the baryons and mesons]https://www.quora.com/Where-do-quarks-get-their-charge#:~:text=In%20general%20particles%20either%20have,make%20the%20baryons%20and%20mesons[/url][/url]

Closer to truth: WHY COSMIC FINE-TUNING DEMANDS EXPLANATION
The electric charge on the proton is exactly equal and opposite to that of the electron to as many decimal places as you care to measure. This is more than slightly anomalous in that the proton and the electron share nothing else in common. The proton is not a fundamental particle (it is composed in turn of a trilogy of quarks), but the electron is a fundamental particle. The proton's mass is 1836 times greater than that of the electron. So how come their electric charges are equal and opposite? Why is it so? There is no reason why this state of affairs could not be different! Actually, there is an infinite number of possible different arrangements which would prohibit setting up stable atoms. Why is the electric charge on the electron is exactly equal and opposite to that of the positron, the positron being the electron's antimatter opposite? That equal but opposite charge is again verified to as many decimal places as one can calculate. So that means the electric charge on the proton and the electric charge on the positron are exactly the same, yet apart from that, the two entities are as alike as chalk and cheese. Why is it for this electric charge equality between different kinds of particles?
https://www.closertotruth.com/series/why-cosmic-fine-tuning-demands-explanation

Jason Waller Cosmological Fine-Tuning Arguments 2020, page 100
Fine-Tuning in Particle Physics  What would happen to our universe if we changed the masses of the up quark, down quark, and electron? What would happen to our universe if we change the strengths of the fundamental forces? And what would happen to our universe if we eliminated one of the four fundamental forces (gravity, electromagnetism, strong force, weak force)? In each of these cases, even relatively minor changes would make the existence of intelligent organic life (along with almost everything else in our universe!) impossible. “The neutron-to-proton mass ratio is 1.00137841870, which looks . . . uninspiring. Physically this means that the proton has very nearly the same mass as the neutron, which . . . is about 0.1 percent heavier”.  At first, it may seem as though nothing of significance hangs on this small difference. But that is wrong. All of life depends on it. The fact that the neutron’s mass is coincidentally just a little bit more than the combined mass of the proton, electron, and neutrino is what enables neutrons to decay. . . . If the neutron were lighter . . . yet only by a fraction of 1 percent, it would have less mass than the proton, and the tables would be turned: isolated protons, rather than neutrons, would be unstable. Isolated neutrons will decay within about fifteen minutes because particles tend toward the lowest possible energy consistent with the conservations laws. Given this tendency of fundamental particles, the slightly higher mass of the neutron means that the proton “is the lightest particle made from three quarks. The proton is stable because there is no lighter baryon to decay into. The ability of the proton to survive for an extended period without decaying is essential for the existence of life. In the early universe, there was a “hot, dense soup of particles and radiation,” and as the universe began to cool, the heavier elements decayed into protons and neutrons. The Universe managed to lock some neutrons away inside nuclei in the first few minutes before they decayed. Isolated protons were still important chemically because they could interact with electrons. In fact, a single proton is taken as an element even in the absence of any electrons—it is called hydrogen. But now imagine an alternative physics where the neutron was less massive, then free protons would decay into neutrons and positrons, with disastrous consequences for life, because without protons there could be no atoms and no chemistry. Neutrons are electrically neutral and so will not interact with electrons. That means a universe dominated by neutrons would have almost no interesting chemistry. A decrease in the neutron’s mass by 0.8 MeV would entail an “initially all neutron universe.  It is rather easy to arrange a universe to have no chemistry at all. If we examine a range of different possible masses for the up and down quarks (and so the proton and neutron), we can conclude that almost all changes lead to universes with no chemistry. Thus, there are firm and fairly narrow limits on the relative masses of the up and down quarks if our universe is going to have any interesting chemistry.

Bohr’s rule of quantization
Electrons are charged particles, they have a minus charge. Because they are in motion surrounding the nucleus, they are accelerating. Any charged particle that is accelerating, emits radiation. This emission of radiation would in turn cause the electrons to lose energy, causing their orbits to decay so rapidly that atoms could not exist for more than a few moments. If they could not occupy only discrete orbitals around the nucleus, then electrons would gradually reduce their energy by radiation and very rapidly lose their orbits. This would preclude atomic stability and chemical complexity. That requires that electrons occupy only fixed orbitals, or energy levels, in atoms. Because of the rule called upon my name, Bohr's rule of quantization, electrons occupy only fixed orbitals. That solves the problem. Quantized energy levels result from the wave behavior of particles. The energy of the electron is deposited at a point, just as if it was a particle. So while the electron propagates through space like a wave, it interacts at a point like a particle. This is known as wave-particle duality. Allowed orbits in atoms occur for constructive interference of electrons in the orbit, requiring an integral number of wavelengths to fit in an orbit’s circumference

In 1913 Bohr proposed his quantized shell model of the atom (see Bohr atomic model) to explain how electrons can have stable orbits around the nucleus. The motion of the electrons in the Rutherford model was unstable because, according to classical mechanics and electromagnetic theory, any charged particle moving on a curved path emits electromagnetic radiation; thus, the electrons would lose energy and spiral into the nucleus. To remedy the stability problem, Bohr modified the Rutherford model by requiring that the electrons move in orbits of fixed size and energy. The energy of an electron depends on the size of the orbit and is lower for smaller orbits. Radiation can occur only when the electron jumps from one orbit to another. The atom will be completely stable in the state with the smallest orbit, since there is no orbit of lower energy into which the electron can jump. The angular momentum of the electron is quantized—i.e., it can have only discrete values. He assumed that otherwise electrons obey the laws of classical mechanics by traveling around the nucleus in circular orbits. Because of the quantization, the electron orbits have fixed sizes and energies.