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What are electrons? (Is why a duck?)

  1. Jul 6, 2003 #1
    I’m confused by a bedrock concept of physics – the electron, but I’m not a scientist and I can’t do the math that’s necessary to clarify what I’m missing.

    My understanding of the subject, such as it is, comes from popular non-fiction like Gary Zukav’s “Dancing Wu Li Masters” and Bill Bryson’s “A Short History of Nearly Everything.” As the explanations of the electron and its behavior in these texts progresses from the general to the specific, the underlying science progresses from straightforward, to arcane, to supernatural. I’ve outlined my understanding below.

    There is an entity called an electron. It is an unambiguous fact that an electron is an electron. That is, even though an electron may be a conglomeration of smaller sub-particles, once those sub-particles coalesce in the one certain way necessary to create an electron, the result is an immutable entity of an established and immutable size.

    But, that immutable entity can, to turn a metaphor back on its source, lead one of two different lifestyles -- domestic or independent.

    Domestic electrons (d-electrons for purposes this exercise) form part of an atom – the quintessential nuclear family. d-electrons circumnavigate their nuclei, but only within specified real estate -- allowed energy states, orbitals, whatever -- in relation to their nuclei. Returning to a simpler time I’ll refer to that real estate as shells.

    Independent electrons (i-electrons), on the other hand, exist independently of the nucleus of an atom. Still an i-electron is an electron, which is an immutable entity.

    There are additional alternatives forms an electron can take, because depending upon how i-electrons separate from the vicinity of an atom they are referred to as different entities. One that fires from atoms residing in a negatively charged metal plate and, for one example, forms an image on a television screen, is a cathode ray. One that fires at a much higher rate of speed from an unstable atomic nucleus is beta radiation. One that is manipulated by technician to perform specific tasks is called a nanomachine. And I’m sure there are others. Still, cathode rays, beta radiation and nanomachines are all i-electrons, and since all i-electrons are electrons, they are all one and the same immutable entity. Rather like you. Whether you dress in a t-shirt and shorts, a business suit or formal evening wear, all three are still you.

    Except for their multiple personality disorder, i-electrons appear to be straightforward, not unlike many familiar everyday entities – a baseball, a grape, a marble. i-electrons are particles that can travel. Scientists can track their path through gases; measure their size and mass; locate them in space; determine where they’ve been and where they’re going.

    d-electrons, on the other hand, are imbued with mystical attributes.

    • Are always there, but don’t exist until we measure them;

    • But when we do measure them (and therefore they exist):

    • they are everywhere and nowhere at the same time; and

    • they can be a wave. Or they can be a particle. At the same time

    • And so on until it is all presumably explained by the uncertainty principle and the square of the wave equation.

    This unfortunately does not complete the personality profile of d-electrons. But boxed into a corner by the weirdness, science has left itself nowhere to turn to complete the profile but the spiritual.

    • d-electrons are electrons (which are the immutable entities)

    • an atom of any given element has only given number of (d-) electrons

    • d-electrons can only exist within their shells, not between them

    • the shell a d-electron resides in at any given moment is a function of its energy state

    • (repeating) d-electrons can only exist within their shells, not between them

    • so to get from one sub-shell to the next, a d-electron makes the quantum leap -- it ceases existing in one shell and simultaneously materializes in another shell, without traversing the intervening space.

    And sciences explanation for this behavior? It’s the only way it can be because the universe made it that way. In other words it has to be taken on faith.

    Anyone who’s read this far should sense my confusion.

    Being a layman, there are a lot of scientific explanations I can’t follow or reason through. But others infinitely brighter than I have done the experiments, replicated the results, done the math, demonstrated the practical applications, and on and on, so I accept their explanations, on what amounts to an act of faith on my part. But it is an act of faith predicated on deference to their education and experience.

    A perfect example, I’m still mystified by radio. The physical explanation notwithstanding, the whole concept still strikes me as nothing short of slight of hand. But it works, so I accept the explanation science provides. But I can’t accept science’s explanation of electron behavior with the same level of confidence.

    I admit that I’m peering at science from a distant viewpoint and trying to bring the images into focus with a crude instrument – an untrained brain. But from my cloudly vantage point, physicists take the explanation of electrons and their behavior to a certain point with science. Then, when the science fails them (perhaps for no better reason than the unavailability of instruments powerful enough to observe the constituent parts of an atom), they stop trying to make the science work and take the leap of faith – it’s the way it is because the universe made them that way. That, to me, is not sufficient for a discipline based on mathematical expression of observable and repeatable phenomena.

    Are we really to accept on faith is that d-electrons disappear from one shell and simultaneously materialize in another one nearby without traversing the space between them? Maybe they sneak through sub-atomic worm holes?

    I’ve seen my twelve year old son do the same trick with a glowing plastic ball. He holds his hands at his side, rocks them back and forth, and makes the glowing ball jump from one hand to the other without navigating the two feet or so between his hands. Being true to his craft, my son would never disclose me how this particular phenomenon occurs. So I have three choices. I can take it on faith that he really made the ball disappear from one hand and simultaneously materialize in the other hand, but I prefer to believe it’s just an illusion and I don’t know how it’s done.

    Accepting that transmigration is a defining characteristic of d-electrons, strikes me as more akin to the dubious reasoning Darwin Award winners employ than endorsing the explanation for why someone can talk into a steel box in one location and I can hear them by listening to a plastic box ten miles or ten thousand miles away.

    And phase-shifting d-electrons are only part of the problem. Science teaches that d-electrons and i-electrons are one in the same immutable entity – electrons. But as nearly as I can tell, the only thing they electrons have in common is a negative electrical charge.

    I can sum up the problem by changing nomenclature for the moment and calling i-electrons “ducks” (as in an “if it looks like a, walks like a, and quacks like a” duck). If I follow the logic of quantum physicists, they have concluded that since a d-electron looks like a goose, walks like a goose and squawks like a goose, then it probably is a - duck. (?)

    Maybe the discordant theories are accepted because it doesn’t matter whether science knows what an electron is. Whatever the metaphysics, the engineering is unassailable. Science can predict with absolute certainty what will happen when d-electrons from one atom come in contact with d-electrons of another atom. Science works with and manipulates combinations of atoms and molecules on a daily basis, so the reason why what they do works many be of no more import than the solution to last week’s crossword puzzle. It’s like when the big news broke that Velociraptors evolved into ospreys, not iguanas. My first thought was: Oh, cool! My second thought was: But, so what?

    Still the explanations are out there, absolute, unassailable, inviolate. If the explanations were any of a number of things – that the electron value of an atom represented not the sum of the charges of its discreet electrons but rather the aggregate charge of its electron shells; that the electron shells were the measurable evidence of the boundary of the attractive power of the positively charge nucleus; that the electron shells were a fifth force; that spins were attractive forces analogous to positive and negative electrical forces, preventing the shell from disintegrating; that when enough of the negatively charged matter comprising the shells separated it could coalesce into discreet i-electrons; that the inverse of the obtuse was the differential of the square root of the wave function – I’d shrug my shoulders and accept it.

    And to do all that science and end up with like wow, man, groovy, time-traveling particles and “even thought they’re almost completely different they’re really the same”, well, it feels more like scripture than science.

    So back to my original question, can someone explain to me in layman’s English what I’m missing? Or extending my duck metaphor and re-naming the d-electron a “why”, (because it acts in such unexplainable ways): Is why a duck?
  2. jcsd
  3. Jul 7, 2003 #2
    So what exactly did you want to know? I doubt i could help you but someone else might be able to if you could clarify your question a bit(thats if it is a question, or maybe i just missed the question).
  4. Jul 7, 2003 #3


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    I definitely concur. I have no idea what you're trying to ask. You sound like you know the concepts behind the Heisenberg uncertainty principle...possibly wave-particle duality, but I'm not too sure if you comprehend the relation between the electron and EM waves. Like Andy said if you keep it a little more pithy there's definitely several posters that can help you.
  5. Jul 7, 2003 #4
    One thing I can say is that it can't be split like you implied it might be. Electrons have been given plenty of different names, because a while back people didn't realise that all these various phenomena such as [beta] -radiation etc. were to due to the electron. Yes electrons do show particle like and wave like behaviour all at the same time (duallity) - but so do all fundamental particles.
    If electrons were a particle though, they would have to volume and thus no shape.

    While it might be hard to get to grips with all this, no mathematical understanding is required, just simple faith and a damn good explanation that no one has been able to come up with yet
  6. Jul 7, 2003 #5


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    An electron has been demonstrated by all theory and experiment to date to be a fundamental, indivisible particle.
    Please refrain from inventing additional, unnecessary terminology.

    The reason that bound and unbound electrons behave differently is not due to any mysticism of the electron itself -- it is instead just due to the fact that the two environments are very different.

    To make a not-so-useful analogy, you're familiar with the fact that free and captive animals behave quite differently. The electron behaves quite differently in different environments as well, and this just shouldn't be bewildering to you.

    Quantum-mechanically, the difference between the behavior of bound and unbound electrons is a result of allowed energy states. The unbound (free) electron experiences (ideally) no interactions with anything else in the universe -- it's just moving uniformly through space. It can have any energy, any momentum, since any arbitrary observer can have any arbitrary relative velocity with respect to it. It has no rules to follow in regards to its energy.

    When the electron -- the very same one -- approaches a nucleus, the rules begin to change. The electron enters a potential -- it feels forces due to the positive charge of the nucleus. The end result is that the electron is no longer able to have any energy; it is only able to have specific (discrete) energies. Thus the electron shells are built around the nucleus. This behavior is not specific to electrons around nuclei either -- bound states of any system have discrete allowed energies. It is a fundamental feature of the universe.
    I don't think anyone has ever called an electron a nanomachine.
    The misconceptions abound. Electrons do not cease to exist unless measured (and in fact I have no idea how you arrived at this misconception). What you're trying to say that they do not have definite properties. If you prepare 1000 electrons in the same state, and then make a measurement on each of them, you will not get 1000 identical answers. Electrons are not everywhere and nowhere at the same time. Every measurement of an electron's position will result in a specific ("crisp") result. However, if you measure it several times, you won't always get the same result. The wave-particle duality picture is one that I wish people would leave behind. In the microscopic world, there are no waves, nor any particles. There is, instead, only one thing, but it exists only in the microscopic world. We can describe the thing with macroscopic wave concepts sometimes, and with macroscopic particle concepts other times -- but the microscopic things are just not like the macroscopic things we'd like to use as analogies, and there is no way around it.
    More misconceptions. Electrons can exist anywhere. Any electron in any shell could potentially be anywhere anytime you measure it. Anywhere in the universe. The likelihood of it being in the next galaxy over, however, is vanishingly small -- it is extremely likely that it will be found within the boundaries of a small region (orbital) around its nucleus. I have no idea what a "function of its energy state" even means, so I cannot comment. The penultimate point you made, that "electrons can only exist within their shells, not between them," however, is patently wrong in every possible sense. The ultimate point, that electrons have to somehow teleport from shell to shell is equally patently, disgustingly wrong. The probability densities do not fall to zero outside the shell. The shell has no boundary. You could define the boundary as the 99% confidence region, but to include 100% confidence, you'd have to include the entire universe. The probability densities overlap. The electron in one shell has a finite, non-zero probability of being measured in another shell. The electron is able to move between shells.
    The only 'faith' one needs is in the axioms of a theory. Quantum mechanics has only a few postulates that deal only with how one mathematically represents a system. Your favorite points of confusion -- the heisenberg uncertainty principle, for example -- are not axioms, they are derived from the axioms.
    Quit your *****ing and buy a textbook.
    How can you even expect these kinds of comments to receive anything in response apart from laughter and derision? You have no idea how science works -- a fact that you've made clear several times now. So why do you feel you understand scientists well enough to make these kinds of statements? I have no idea what it's like to be a surgeon. I therefore refrain from making comments about how surgeons think. It is offensive that you seem to think you know how I think. It just makes you look stupid.
    Of course not -- and if you had even a passing knowledge of any of the concepts you think you understand, you'd realize it.

    You are perhaps one of the worst cocktail-party physicists I've ever heard. You are the result of a long history of reading crap paperbook "science" books. You know some of the buzzwords, some of the concepts, and some of the bits that give students problems. However, you don't seem to recognize how pathetically ill-equipped you are to do anything but talk to other pathetically ill-equipped people around a punch bowl.

    You now have a choice. The answers you seek are out there. You CAN understand quantum mechanics. However, the answers are not in paperback NY Times bestsellers -- they do nothing but distort the truth in order to package it in English prose. Go buy some textbooks -- we can recommend which are good starting points for your level of mathematical ability -- and teach yourself the goddamn theory. Until then, do not even attempt to tell us scientists that "we stop trying to make science work."

    - Warren
  7. Jul 7, 2003 #6
    Hey Warren...
    Take it easy tiger!!!
    The guy just wants to learn something new.
    He's only as baffled as we all were when we
    first learned about all this stuff!
  8. Jul 7, 2003 #7
    (Quote from the original post)
    If your book is based on this statement, then I think it's not a very realistic book. As far as I understand, 'absolute certainty' is not a concept used in science.
  9. Jul 7, 2003 #8


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    I doubt that. It looks more like a post-and-run wacked out pseudo-scientific theory to me. The goal isn't to learn, but to spread his idea and possibly (if he comes back) to hock his website or book.
  10. Jul 7, 2003 #9
    Man you guys are paranoid!!!

    If you're not skeptical about the things youve been
    taught, how do you ever hope to come up with new ideas?

    "Given enough time, anyone can come to understand physical
    principals, but it takes an imaginative mind to invent new
    ones" - A famous quote by Steven Sterley
  11. Jul 8, 2003 #10

    Could you please go into more detail about that "one thing"?
  12. Jul 8, 2003 #11
    If we measure this guy's theory

    do you think it will disappear?
  13. Jul 8, 2003 #12


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    Staff: Mentor

    Not paranoid, just cynical.
  14. Jul 9, 2003 #13
    What is an electron

    For Andy and E8, maybe my initial post is long winded and flip, but all I’m looking for is a comprehensible explanation for two concepts: free electrons and electrons that are the constituent part of atoms are one and the same; and when an electron becomes a part of, for example, a Beryllium atom it is one of 4 discrete entities, each identical to a free electron, orbiting (or whatever electrons do) in relation to the nucleus of that atom.

    The problem I see is summed up by Ace of Spades (While it might be hard to get to grips with all this, no mathematical understanding is required, just simple faith and a damn good explanation that no one has been able to come up with yet”) and for all his anger, Warren (“There is, instead, only one thing, but it exists only in the microscopic world. We can describe the thing with macroscopic wave concepts sometimes, and with macroscopic particle concepts other times -- but the microscopic things are just not like the macroscopic things we'd like to use as analogies, and there is no way around it.”)

    Axiomatic statements like these seem to me to be too much like the faithful preaching gospel. Patently neither is correct. There are explanations other than faith, and there are ways around the gaps in our knowledge, but humans don’t (and may never) possess the technology to discern them.

    Technology never stops evolving and with new technology comes new understanding. For one example, Warren says “An electron has been demonstrated by all theory and experiment to date to be a fundamental, indivisible particle,” but (again only from popular sources) I’ve been led to believe that the building blocks of the universe are not protons, neutrons and electrons, but ever expanding menu of sub-atomic particles -- muons, pioons, hyoperons, mesons, leptons, and so on.

    What I suppose I’m looking for is leads to cutting edge thought by legitimate physicists that goes beyond present orthodoxy. Not that present orthodoxy won’t in the end prove to be correct, but are there any new theories in the canon to prove (or disprove) it?
  15. Jul 9, 2003 #14
    leptons = electrons and corresponding neutrinos
    Quarks and leptons are the fundamentals.
    Quarks make up baryons and mesons.

    Something to remember.
  16. Jul 9, 2003 #15
    Wow! Warren must have an electron stuck where the sun don't shine. Now I know where the term Mad Scientist came from.

    It does'nt take a rocket scientist to understand that Steven Kalb is out fishing for whatever bites. Even a Mad Scientist could come to grips with this, or maybe I'm wrong about the Mad Scientist.:wink:

    I do have a few question regarding the electron in regards to it's particle wave duality.

    When is an electron a particle?
    When is an electron a wave?
    Is an electron a particle and a wave at the same time?
    Does an electron move at C at all times?
  17. Jul 9, 2003 #16
    Well I CAN answer the last one with high certainty. Electrons don't move at c. They have mass and therefore cannot. In fact in a wire, electrons hardly move at all. They slowly migrate down, lets say, a copper wire due to resistance. They can be accelerated to near the speed of light but that is about it.
  18. Jul 9, 2003 #17

    Tom Mattson

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    Re: What is an electron


    The theories we have are tested. The statements that make their way to physics textbooks are the ones that survived after the bad theories had been falsified by experiment.


    In the Standard Model, the building blocks of the universe are quarks and leptons. The pions, hyperons and mesons are all composed of quarks.

    What you are looking for then is some information on String Theory, which is out to replace the Standard Model (which is a union of two quantum field theories, electroweak and QCD).
  19. Jul 9, 2003 #18


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    An electron will appear to you as a wave if you do an experiment that depends on its wave properties (such as two slit interference). It will appear as a particle when you do an experiment that depends on its particle properties (such as deep inelastic scattering).

    There is a princple of physics (like an axiom) called the Complementarity Principle that says you can't do an experiment that really truly evokes both properties at the same time.

    Maybe you don't like an explanation in terms of experiments people do? That's the way quantum mechanics (and relativity) describe the world. You won't get any "deeper" answer.
  20. Jul 9, 2003 #19
    Ha, its about time someone recognised my intelligence! Bit obvious that your new hear because if you had been hear any length of time you would realise that i have a very limited knowledge of physics relative to many of the others that use this forum.
  21. Jul 9, 2003 #20
    Self ajoint

    {{{{An electron will appear to you as a wave if you do an experiment that depends on its wave properties (such as two slit interference).}}}

    You can do a slit experiment with electrons and it will work like the photons do?


    {{{Well I CAN answer the last one with high certainty. Electrons don't move at c. They have mass and therefore cannot. In fact in a wire, electrons hardly move at all. They slowly migrate down, lets say, a copper wire due to resistance. They can be accelerated to near the speed of light but that is about it.}}}

    But while they are slowly migrating down the wire are they not also revolving around a nucleus at or near C? If you could place an elctron by whatever means in the dead of space - Could it just sit there, or would it be moving at or near the speed of C?
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