This is really bothering me lately and I'm trying to determine what are the best and most current explanations. What on Earth is going on here and how can the electron be going through both slits at the same time?

Any callers?

You can have a delocalized wave pass through both slits at the same time, right?

Really, it's not that it's passing through both slits at the same time, it's that you don't know unless you measure, and if you measure after your particle has passed through the slits, it behaves like it went through both. Why? We really don't know, it just does. Why do classical particles act to minimize their action integral? They just do.

What on Earth is going on here and how can the electron be going through both slits at the same time?
It seems pretty obvious that it can't if it's like a little marble.

So, because the electron behaves like it's going through both slits, it's obviously not behaving like a little marble. Therefore electrons aren't like little marbles.

So, what are they like? Well, they're like electrons... and that's the way electrons behave, I guess.


Hmmm... I don't think that was terribly useful, was it...

Hmmm... I don't think that was terribly useful, was it...


Ahem, not as useful as you normally are Pete :rolleyes:

You see, I'm thinking that an electron is not what we think it is and this makes me curious.

And so I'm wondering if anyone has any groundbreaking ideas on what might be happening here.

Nothing groundbreaking, just that hey subatomic particles aren't what we classically think of as little marbles flying around, they're more like wave packets flying around and acting like waves. We've known this since the Davisson and Germer experiment many decades back.

Nothing groundbreaking, just that hey subatomic particles aren't what we classically think of as little marbles flying around, they're more like wave packets flying around and acting like waves. We've known this since the Davisson and Germer experiment many decades back.


Do electrons fired at 3 or 4 or 5 slits exhibit wave patterns too?

Yes. Electrons in free space exhibit wave properties. The slits just create interference patterns which are really telling of wave-like properties.

Yes. Electrons in free space exhibit wave properties. The slits just create interference patterns which are really telling of wave-like properties.


And so if you had, say, 4 slits and were observing an interference pattern, then when you try to look at the electron going through any one of the four slots, I take it you then get a pattern as if there were only three slits, yes?

Actually, at least one edge of each slit scatters the light that goes through them.

Actually, at least one edge of each slit scatters the light that goes through them.


Hold on, we're talking electrons here, not light.

You see, I'm thinking that an electron is not what we think it is and this makes me curious.
What do we think it is?

If anyone is interested and has any idea of where to find a Physics 101 textbook, they might find a page or two that describes wave-particle duality.

This is a great link for any readers who want to read about the experiment...

http://www.upscale.utoronto.ca/GeneralInterest/Harrison/DoubleSlit/DoubleSlit.html

The famous double slit experiment has been performed with more than two slits and with objects as large as carbon atoms. :eek:

http://physicsweb.org/articles/world/15/9/1

Pete,

Well, I know it’s got negative charge and is arranged around the nucleus in quantum orbits. I know it’s a Lepton, which is within the Fermion class and I know its mass and charge etc – that’s about it.

It’s just that I’m trying to work out what the problem is with regard to the double slit experiment.

Science says it can’t explain how the particle can travel through both slits at the same time when it can only be viewed in one slit. And I’m trying to seek an explanation.

For instance, perhaps the electron is emitted as a wave and emanates outwards in all allowable directions, but can only be viewed once, at which point it discharges and disappears. This way, the electron WOULD obviously travel through both slits.

So why can you fire an electron and get a single hit like a bullet? Well, is it possible for the wave to travel outwards but collapse to a single point once it strikes something?

123

The famous double slit experiment has been performed with more than two slits and with objects as large as carbon atoms.

Just a little curious here, would we get the same result if we used a compound, such as water molecules for the experiment?

According to quantum theory, if you drove your Hummer through the slits, yes.

Did you ignore or link up to my link?

The electron is going through "both slits at the same time". In fact, unless you measure which slit it's going through, it does not even make sense to ask that question. You can't know which slit the particle went through unless you measured it, and as such asking "which slit" doesn't make sense. It BEHAVES as if it has gone through both, so we infer that it has.

As for the Hummer comment, this is, of course, true. However, if you want to think of the Hummer as a single particle and that single particle being in the state of a Gaussian wave packet in free space, it's going to have a really tight wavefunction, so it will behave fairly deterministically.

Just a quick poll here: how many people posting on this thread have actually taken a course on quantum mechanics?

The scientific interest may be piqued by truly weird things pronounced by Quantum Physics which, no matter how strange they seem, are claimed to be true.

Formal classes are certainly wonderful in their milieau, although they are not the only method to learn about important subjects.

If someone is interested in Quantum Physics and wishes to start off on the ground level, without any scairy math, there are several good layman language books. One that I consider very good is "Schroedinger's Kittens" authored by John Gribbin. :cool:

CANGAS,

The problem with this is that the most physical way to explain this is with wave functions, but I cannot talk mathematically about wave functions if most of the readers do not know what they are. If I can talk about this as propagators and such, all's the better.

Honestly, to really learn the subject you have to get into the math because it guides you through the physics, and this is true for any physics subject. If the math doesn't support something think may happen, then there is one of two things: the theory is wrong (for established things like QM this is unlikely unless you're trying to break QM) or what you're conjecturing will happen cannot happen. Removing math from physics is like removing books from a literature class. All you're left with are these nebulous concepts without any grounded basis of discussion.

Phys:

Did you notice that the thread starter couched the original question, and subsequent comments and questions, in non mathematical, layman language?

I noticed it.

Sayonara. :cool:

^^^^^ Ah, your smugness belies your wisdom.

Well, OP, basically here's all there is to it. Particles behave more like waves than localized objects, and waves can interfere with each other. If you measure which slit the "particle" went through, then the particle will begin totally localize and disperse from that one slit as if it's the only source. If you don't do this, then in passing through each slit the waves will interfere like light does. You can observe this effect experimentally, too.

^^^^^ Ah, your smugness belies your wisdom.

Well, OP, basically here's all there is to it. Particles behave more like waves than localized objects, and waves can interfere with each other. If you measure which slit the "particle" went through, then the particle will begin totally localize and disperse from that one slit as if it's the only source. If you don't do this, then in passing through each slit the waves will interfere like light does. You can observe this effect experimentally, too.

Ok, so can we assume that an electron isn't really a particle but more like any other wave eminating from one point and travelling out in all allowable directions. Is it ok to think of it like that being as we KNOW it travels through both slits?

Phys:

Your garbled syntax belies veracity in your attempts to explain Quantum Physics.

It is important to note that since not everyone is a Pulitzer Prize grade writer, anyone can write badly, not just you. My reaction to your garbled syntax is because it leaves me unable to understand what you are trying to communicate. This causes me to conclude that you may be totally incorrect, scientifically.

You seem to have told us both that an electron really does NOT, and also, that an electron really DOES travel through both slits.

If you do know which case is true according to currently accepted QP, why don't you clarify for us now, in clear grammar, if possible?

Ok, so can we assume that an electron isn't really a particle but more like any other wave eminating from one point and travelling out in all allowable directions. Is it ok to think of it like that being as we KNOW it travels through both slits?
An electron isn't really like a particle. But it's not really like a wave either.

But why should it be like either, anyway? Why not accept that it's like an electron, which is unlike anything we're familiar with?

Pete has hit the nail on the head. The electron is neither a classical wave nor a classical particle. Attempts to put the electron in one classical box or the other led many pioneers of quantum theory to talk at great length about the mysterious wave particle duality. With our rather more complete modern understanding, we now know that the electron is a quantum unity rather than a classical duality.

Pete has hit the nail on the head. The electron is neither a classical wave nor a classical particle. Attempts to put the electron in one classical box or the other led many pioneers of quantum theory to talk at great length about the mysterious wave particle duality. With our rather more complete modern understanding, we now know that the electron is a quantum unity rather than a classical duality.

Well, not exactly. The particle and wave interpretations are still used in quantum theory. It's just been recognized that they are equivalent to eachother. This is why it's called the "Particle/Wave Duality" rather than the "Particle/Wave Paradox." That is to say, all particles ARE waves, and all waves ARE particles; which one you choose to in terms of is an issue of convenience. The question of wheter an electron (or whatever) "is" a particle or a wave is literally meaningless. There simply is no distinction between the two.

I disagree, the electron is not a classcial particle or a classical wave, and it certainly isn't both. The statement that particles are waves and vice versa makes no sense. This is exactly why every student of quantum mechanics is baffled by this statement. It is logically inconsistent with the ideas of classical particles and classical waves that they have in their head. Electrons are quanta, and under certain experimental circumstances they can give results that can, if we didn't know better, be interpreted as classical wave like or classical particle like. But we do know better, and unless you change your definition of wave and particle then the electron isn't a wave or a particle. If you do change your definition then you haven't really done anything except give me another name for quanta, and quanta is shorter than "dual wave-particle object".

"In order to interpret these results, one is forced to conclude that an electron interacts with both slits simultaneously." Page 953.

"In this situation, one cannot say that the electron is in state 1 or in state 2. It is only correct to say that that the electron is in both states, since the wave function is a combination of the two states. In effect, we can say only that the electron passes through both slits!" Page 954.

Physics for Scientists and Engineers, with Modern Physics, Second Edition.
Raymond Serway, author.
ISBN 0-03-004854-0.

P M: My compliments to you. You spray words around with the best of them.

I disagree, the electron is not a classcial particle or a classical wave, and it certainly isn't both. The statement that particles are waves and vice versa makes no sense. This is exactly why every student of quantum mechanics is baffled by this statement. It is logically inconsistent with the ideas of classical particles and classical waves that they have in their head. Electrons are quanta, and under certain experimental circumstances they can give results that can, if we didn't know better, be interpreted as classical wave like or classical particle like. But we do know better, and unless you change your definition of wave and particle then the electron isn't a wave or a particle. If you do change your definition then you haven't really done anything except give me another name for quanta, and quanta is shorter than "dual wave-particle object".

Never heard the term "quanta" used as above. All of the quantum phycisists I know refer to electrons, photons, etc. as "particles." Perhaps you can give me a better idea of what you mean by "classical wave" and "classical particle"? And most students of quantum that I've met are already familiar with wave/particle duality from the classical setting of geometric optics. It's basic high school physics that all "waves" act like "particles" when the features they interact with are very large compared to the wavelength. That right there is the wave/particle duality in a nutshell. It's not until quantum that you see what you thought were particles (electrons) acting like waves, but it doesn't require any real adjustment. You just recognize that what you thought were particles are actually waves with very high frequencies.

I recall being kind of disappointed when I realized that was all there is to it.

Peggy Lee sang that in a song, "Is that all there is?".

Quantum Physics is both, simultaneously, much more simple than we might think, and, much more complicated than we might want.

Huh? Wha'd I say?

Physics Monkey,

Can you please explain to me what the mysteries are that surround the Feynman Double Slit Experiment? Are there any?

CANGAS,

I'm sorry, I thought my post was simple coherent English using terms everyone who has studied quantum mechanics would know. In particular, the word "quanta" was first introduced by Planck way back when. In the future, it may help to read some background material on the discussion, this will help you understand what were talking about.

quadraphonics,

Thank you for your reply. It is true that most physicists just call the electron a "particle" but the important thing to remember is that they don't mean a classical particle. When a student from classical mechanics hears the word "particle" they think of little rigid balls bouncing around, but this isn't what the electron is. The modern use of the word "particle" by physicists is simply another way of saying "quanta", I used the more precise but less common term here for explanatory purposes.

Regarding your other points, I have to disagree. Classical particles are discrete point like objects. Classical waves are extended continuous things. There is a qualitative difference in the number of degrees of freedom in both cases. When one tries to put the two together in a purely classical fashion, well known difficulties arise. One can say that classical waves can be localized and can move like classical particles, but only to a certain limited extent. Classical particles also don't behave like classical waves except in certain limits. Now, suppose I prepare an electron in a plane wave state in a box of some volume. When you measure the position of that electron, you always find it sits at just one place (within the limits of your apparatus), classical waves just can't do that. On the other hand, it is well known that electrons can diffract, classical particles can't do that. Rather than saying the electron is somehow two contradictory things, call it something new.

I think PM pretty much summed up anything useful I might have had to say.

The key feature is that an electron is something completely separate from the "classical experience" I guess you could call it. It's this thing that does something and is completely indeterminant until we measure it, and then we can know exactly where the particle is (remember "exactly" with the caveat of experimental error and such). It's not some wave with amplitude, nor is it some deterministic particle. It's neither at all.

Both PMs are of course right, but some may at least be amused by the old alternative theory (not original with me) but :cool: :

On Monday, Wen. & Fri - Electron is particle
On Thue, Thru & Sat - Electron is a wave.
On Sundays, God told physicists to rest, not do experiments.

PhysicsMonkee:

Having read more than "a" book about Quantum Physics, I do know what you are talking about, and I know what the genuine experts are talking about.

And I know when you are saying the same things as the real experts, and I know when you are not.

Are you happy with your batting average?

PS Didn't somebody ask you a question about Quantum Physics mysteries?

A serious student of Quantum Physics who wishes to start their study with a strong dose of scairy math might beg, borrow or buy :eek: :

The Physical Principles Of The Quantum Theory
by Werner Heisenberg
published by Dover
Library Of Congress Catalog Card Number 486-60113-7


A serious student of Quantum Physics who wishes to study up to date concepts, with no math, written by a genuine expert, might beg, borrow or buy :eek:

The Fabric Of Reality
by David Deutsch
published by Allen Lane The Penguin Press
ISBN 0-7139-9061-9

The double slit experiments just keep going and going and going. They are up to Iodine MOLECULES now. :cool:

http://www.lifesci.sussex.ac.uk/home/John_Gribbin/quantum.htm

Cangas,

You have quoted a book written by Werner Heisenberg in, if I recall, the 1920s. We have a slightly more revised interpretation of quantum mechanics from then. I've also read Heisenberg's book, but I've also read a lot more than that. If all you've read are sixty year old Dover editions, I strongly advise that you pick up something from about 1985 onward.

PhysMach:

As usual, in your self elevating mode, you have misstated circumstances. The old book, from 1930, as you well know, if you really know very much about the subject, was plainly presented as a means of acquainting a new student with the math of Quantum Physics.

It will be of great interest to anyone who actually does know something about Quantum Physics to hear from a really knowledgeable expert like yourself: specifically which mathematics and concepts in the old book are now PROVEN WRONG? Maybe some are. Tell us which ones. And do a better job than when you fumbled and bumbled around and did not know that an electron goes through BOTH slits of the double slit experiment.

It is completely unbelievable that you can claim to be some kind of expert about Quantum Physics and yet you did not know to plainly state the universally accepted, among professional Quantum Physicists, conclusion that each electron goes through both slits.

And obviously your seeing eye dog did not inform you that, in the same post that I mentioned the old book, I also mentioned a new book, The Fabric Of Reality, written by a real expert, in 1997.

You do this kind of misleading dodge so often. How can it be an honest mistake?

I am tired of argueing with you about things you know I did not say and things I know you do not understand.

Heisenberg's book, as I recall (can't seem to find my copy around), was mostly listing out the experimental evidence regarding quantum mechanics, and discusses the mathematics a little bit. The fact is that this book predates the concept of path integration by at least a decade, and most modern books don't look at quantum particles as being in some sort of "wave function" to begin with. That's viewed as the position representation of some underlying state that is basis-independent. Our understanding has evolved quite a bit since the 1930s.

As for your second book, I shouldn't have to be critical of a piece of pop-sci to get the point across that using it as a reference is silly and does not give you much leg to stand on. I don't care if this Deutch fellow is an expert in his field, popular science books are inevitably misleading with regards to the interpretations they give, and they frequently talk about the author's views, which may not be the general views of the community as a whole (I haven't read Deutch's book or studied his writings with much detail, but this rule generally holds even for the most credible of writers).

Try reading Sakurai, Shankar, or Baym. Any one of those three gives a much more modern interpretation of quantum mechanics. I also strongly advise you against criticizing someone else's qualifications when (a) you haven't presented your own and (b) you don't know theirs. It's like walking into a dark cave without know what's going to come back and bite you on the ass.

When a self alledged Quantum Physics EXPERT claims, as you have done openly, that electrons in the double slit experiment do not go through both slits, then that self claimed EXPERT has no alternative but to be known as a fraud, no matter how much crap they spew out of their keyboard.

I have never mentioned qualifications. You have raised the issue, obviously as a Red Herring.

Qualifications are not the issue here, although you desperately try to divert attention. Facts are the issue. You have blatantly misrepresented the fact that you have claimed that electrons do not go through both slits, while every real expert, from Feynman on down has plainly stated that they undeniably do go through both slits.

Why don't you edit your prior post? Maybe I have not saved it to my hard drive as proof.

If qualifications are the issue, why isn't your dumb ass impressed that you are directly contradicting Feynman?

Are you halucinating that you, not Feynman won the Nobel , because you say they do not go through both slits, whereas he said they do?

And, Fizz, I have challenged you to show us what writings of Heisenberg, in your infinite wisdom, you declare to be PROVEN WRONG. I ain't seen nothin' yet.

You do realize that you are essentially implying that everybody from Heisenberg through Feynman Through Deutsch has it wrong but YOU have it right?

YOU are going to bite MY ass? IN YOUR HALUCINATION. GET STARTED, M F. Oops, typo, of course I mean F M. ( Fizzix Munchkin ).

CANGUS, I had no problem understanding PhysMachine's posts. Why do you? Suppose
you tell us which state of the electron passes through both slits, the wave function
or the particle.

Now for a question I have. If a single electron is emitted towards two open slits and
measurements are taken behind each of the slits simultaneously, how many electrons
will be measured? ONE, correct? Behind only one of the slits, correct?

CANGAS:

A little spellchecking can go a long way. Your semiclassical attempt to understand quantum mechanics is outdated. It makes no sense to say "the electron went through this slit" or "the electron went through a slit" unless you measure that it goes through some slit. You've misunderstood everything that I've said from the beginning. What I'm saying, and what is the generally accepted interpretation, is that it is nonsensical to ask the question "which slit did the electron go through?" unless you are measuring as such. If you don't make this measurement, the distribution you get on the other side of the two slits looks as if a classical wave has passed through both slits. But this is for a classical wave: electrons are in no way classical. Until you can get past your attempts to classically describe a quantum particle, nothing you say to me has any meaning.

2inquisitive, you will measure one electron hit on the detector past the two slits. If you do this measurement many times with one electron at a time, you will observe that the particles randomly distribute themselves with diffraction patterns and such that are identical to those of a classical wave. Don't let that fool you, thought. There is nothing at all classical about an electron.

PhysMachine, my example was using TWO detectors, one behind each slit to determine
which of the two slits the electron passed through. In this version of the double slit experiment, only one electron is measured to pass through one or the other of the slits
and the fringe pattern disappears, no diffraction pattern, due to the collapse of the wave function upon measurement. The electron is neither particle or wave, but something else not completely understood by current physics.

2inquisitive,

The electrons will form a distribution over the entire wall behind the two slits, so putting a detector behind each one will lead to large losses in data, and won't tell you anything.

Actually, the electron is pretty well understood by current physics. It's just not a classical thing, so any attempt to base intuition on an electron based on classical thought is doomed to failure.

In a bizarre twist of Physics, lets suppose that light rays were discovered to travel backwards from detector to emitter. Lets imagine that in this bizarre new world the so-called emitter does quite the opposite to what one would expect. Rather than the orthodox view of the emitter releasing its store of energy to its surroundings, instead please consider the emitter to be extracting energy from its surroundings in whatever form the emitter is constructed to do so. In other words, energy flows the opposite way. I am fully aware that this is REALLY stupid but I want some feedback so I can further develop my thought processes regarding quantum dilemmas. I’m interested to learn more about the possibilities of instantaneous communication between source and detector and this will help me develop more ideas.

So, just for one minute lets say that the emitter (a laser) works the opposite way round such that when we “charge” its battery, in actual fact we are taking energy AWAY from it wrt its surroundings and turning the laser on means that the laser resonates with its surroundings and “sucks” back the energy to gain net equilibrium. The laser looks brighter to our eyes because it is resonating with our eyes more vigorously and “sucking” more energy. (Yes, I know – stark raving bonkers!!!)

I know this is a weird thought experiment but how would this affect the way we think about the double slit experiment and quantum mysteries if this were the case?

...(Yes, I know – stark raving bonkers!!!)...Yes it is, but you may want to investigate what the Greeks thought about vision as for them it consisted of two parts. One was the sunlight falling on an object and interacting* with it. The other part came out of the eyes, ray like, also struck the object and felt the interaction that the sunlight had produced. Sort of like you can feel the difference between sandpaper and glass surface.

All vision worked this way, so of course you could not see the rays passing thru space towards the object, any more than you can feel the tactical nerves that are working for you. - You only feel the object with your tactile system's nerves or see the object with your visual system's rays.

* faint light could not produce the color part of the interaction, and opaque objects blocked the eye rays so you could not see thru opaque thing to the objects behind. All in all, not a bad theory.

When a self alledged Quantum Physics EXPERT claims, as you have done openly, that electrons in the double slit experiment do not go through both slits, then that self claimed EXPERT has no alternative but to be known as a fraud, ...No, Physics Machine is correct. The "alternative" you are omitting applies to you. It can happen that someone, who does not even understand QM, makes many claims about it. This does not prove you are a "fraud" - only that you have not studies QM enough, never actually used it for calculations, etc.

Ok, so although this notion is impossible, if there were a kind of carrier wave that communicated information, how might this help Quantum mechanics enigmas, I wonder?

This is why I am asking you for one moment to imagine that experiments using down converters and beam splitters would be anywhere near as perplexing if we imagined the light reversing its direction throughout the experiment, as explained above.

Cheese.

Why have so many of the most highly respected quantum physics experts gone on public record saying that one electron goes through both slits?

Are they all nutz, but you good old boys REALLY know was hapni'n?

Why have so many of the most highly respected quantum physics experts gone on public record saying that one electron goes through both slits?

Are they all nutz, but you good old boys REALLY know was hapni'n?

cangas,

I think you are mistaken. An electron will seemingly go through both slits OR only one slit depending on how the experiement is performed. Let me clarify. Say you are to perform the double slit experiment by shooting only one electron at a time and you DON'T make any experimental attempts to determine the actual position of the electron as it passes through the slits. Then, on the screen you will see the classical interference pattern. However, if you experimentally track the position of the electron as it passes through the slits then you will see that the same electron only pass through one slit. So, the interference pattern is lost and we just see a seemingly random pattern on the screen which is consistent with Heisenberg's uncertainty principle. So, as you can see, the results of the former experiment are explained by concluding that the electron must have passed through both slits while the latter results clearly show that the electron only passed through one slit. So it's both!

Acutally, as an aside, interestingly enough the whole basis of Quantum Computing is based on this superposition principle--that the electron is in "two places at once" which will drastically increase computer processing .....facinating topic.

If you still don't believe me, check out this site for a really good explanation complete with animations:

http://www.upscale.utoronto.ca/GeneralInterest/Harrison/DoubleSlit/DoubleSlit.html#TwoSlitsElectrons

So it appears that they are not "all nutz" and the "good old boys" really do know what they're taking about. In the future it would be wise to actually read and understand the previous posts before making sweeping accusations that really do nothing but reveal your own ineptitude.

I would like to understand WHY observation changes the outcome.

Simple enough question, is there a decently formulated answer?

I would like to understand WHY observation changes the outcome.

Simple enough question, is there a decently formulated answer?

This is not a technical answer. That is I only want to make a general point. If your assumption that observation means seeing it then you would be wrong.

Observation in this context means "measurement" of some sort which normally entails some form of interference.

That nuance was understood.

Does anyone have a reasonable theory as to why measurement influences the outcome?

That nuance was understood.

Does anyone have a reasonable theory as to why measurement influences the outcome?I think it is just because in order to measure it you have to hit it with a photon. The photon changes its motion.

Of course, that seems to presuppose the "particle" view of the electron. And until you hit it with that photon it seems to be more of a wave. So I guess it is not really a satisfying answer.

-Dale

Ok, so you have one photon with no certain locality heading for an interaction with another wave/particle with no certainty of locality? How do non localized waves interact, and what is it about this interaction that generates what we percieve to be localized particle phenomena?

How do non localized waves interact?By transfering a somewhat indeterminate amount of momentum :). Sorry, if there is a better answer to this I certainly don't have it.

-Dale

chirality:

I am glad you apparently finally found out how to pull up Wikipedia on your screen. Keep trying! Who knows what else is available that would be just right for you!

I would genuinely enjoy participating in the arguement you are trying to start, for the same reason that Mickey Mantle genuinely enjoyed batting against knuckleball pitchers: he had such good eyesight and reflexes that a knuckleball was the easiest pitch for him to hit, and he was so strong that he did not need the wimpy slow speed of the pitch to provide any of the momentum. He hit his longest home runs off of knucklers. The fact is that I have work to do, work of even more importance than engaging in a pointless arguement with someone like you.

However, I do take it as a compliment that you gave it your best effort to bait me, even going to the extent of transparently lying about my statements in my posts. I must call you a real master baiter.

:D

the electron...



its a particle on monday, wedsnday and friday...
but its a wave on tuesday, thursday and saturday...

on sunday it rests.

-MT

Quantum interactions are considered to ubiquitously conserve momentum and kinetic energy, measured before and after the complete interaction.

However, during the interaction there are moments when such are indeterminate, permitting the weird non-classical results.

When the dust settles, the momentum and kinetic energy books have to be in balance.

Quantum physics don't want no embezzling 'round here.

Hehe, QM, the cosmic loan shark and bookie :D

-Dale

This is really bothering me lately and I'm trying to determine what are the best and most current explanations. What on Earth is going on here and how can the electron be going through both slits at the same time?

Any callers?
Dav5, here is a model to chew on.

This is an unpublished version.
To be very brief, JS Bell made the point that any qm model that did not ecplicitly include nonlocal forces was incomplete (See 'speakable and unspeakable in qm', a collection of papers on the subject by JS Bell). Unlike the current or standard model,the following is not as spooky. Once the electron is looked as a 'spin particle', with two possible modes, up or down , plus- minus, etc, one does not have to invoke a wave-particle duality to the electron just to get it through two holes simultaneous. If the mass of the electron goes through one hgole and the 'nonlocal spin mode', element of the spin state goes through the other hole, then the so-called wave interference effects will be observed, otherwise the electron distribution on the scintillating screen is 'gaussian'.

Feynman, in discussing the impossibility of a different mode (Vol III 'Lectures on Physics', Chapter 1), than that adopted mode, he comments that "otherwise the electron would have to know ahead of time which hole it was going to traverse".(paraphrasing a bit). This should have been looked at a little closer as this is what apparently occurs.

The electron is made up of a massive 'core' and a charge field surrounding the mass. Without giving any attributes other than a general descrtiption of 'mass' consider the electron as it approaches the holes. The charge field -precedes the electron's arrival at trhe surface contqaining the holes., and the electron therefore finds its forward motion impeded by the reflected charge dirsrtribution from the surface of the material containing the holes. The impeded motion wil occur over the whole of the surface with the exception that there will be no reflection (or certainly a reduced reflection from those points defining the holes). Therefore the electron will take the path of least resistant, or minimum potential trajectory and enter one of the holes. The observed 'spin vector' is assumed located internally to the electron, yet the spin mode not actualized is relegated to a 'nonlocal status'. This assumes the electron has a dynamic +-+-+- switching mechanism operating until polarized by the inhomogeneous magnetic field as defined in Stern-Gerlach experiments. The changing charge field distribution in space of the electron during the reflection process creates the condition for an inhomogeneous magnetic field that effectively provides an 'equivalent' magnetic field volume seen in more controlled Stern-Gerlach conditions. There is no ambiguity regarding a 'nonlocal' entitiy being localized in the other hole during transition through the holes, as this polarizing condition localizes the nonlocal elements at least during the transition through the holes (this is also the case in transitioning particles, spin-1 included, seen in Stern-Gerlach experimental results, or during transition through the inhomogeneous magnetic volume of the Stern-Gerlach segment. In other words, if nonlocal elements have a real affect on the particle, there must be a local-nonlocal interface appearing under certain conditions at some instant of time(s).
Geistkiesel

This is really bothering me lately and I'm trying to determine what are the best and most current explanations. What on Earth is going on here and how can the electron be going through both slits at the same time?

Any callers?
Dav57, here is a model to chew on.

This is an unpublished version.
To be very brief, JS Bell made the point that any qm model that did not ecplicitly include nonlocal forces was incomplete (See 'speakable and unspeakable in qm', a collection of papers on the subject by JS Bell). Unlike the current or standard model,the following is not as spooky. Once the electron is looked as a 'spin particle', with two possible modes, up or down , plus- minus, etc, one does not have to invoke a wave-particle duality to the electron just to get it through two holes simultaneous. If the mass of the electron goes through one hgole and the 'nonlocal spin mode', element of the spin state goes through the other hole, then the so-called wave interference effects will be observed, otherwise the electron distribution on the scintillating screen is 'gaussian'.

Feynman, in discussing the impossibility of a different mode (Vol III 'Lectures on Physics', Chapter 1), than that adopted mode, he comments that "otherwise the electron would have to know ahead of time which hole it was going to traverse".(paraphrasing a bit). This should have been looked at a little closer as this is what apparently occurs.

The electron is made up of a massive 'core' and a charge field surrounding the mass. Without giving any attributes other than a general descrtiption of 'mass' consider the electron as it approaches the holes. The charge field -precedes the electron's arrival at trhe surface contqaining the holes., and the electron therefore finds its forward motion impeded by the reflected charge dirsrtribution from the surface of the material containing the holes. The impeded motion wil occur over the whole of the surface with the exception that there will be no reflection (or certainly a reduced reflection from those points defining the holes). Therefore the electron will take the path of least resistant, or minimum potential trajectory and enter one of the holes. The observed 'spin vector' is assumed located internally to the electron, yet the spin mode not actualized is relegated to a 'nonlocal status'. This assumes the electron has a dynamic +-+-+- switching mechanism operating until polarized by the inhomogeneous magnetic field as defined in Stern-Gerlach experiments. The changing charge field distribution in space of the electron during the reflection process creates the condition for an inhomogeneous magnetic field that effectively provides an 'equivalent' magnetic field volume seen in more controlled Stern-Gerlach conditions. There is no ambiguity regarding a 'nonlocal' entitiy being localized in the other hole during transition through the holes, as this polarizing condition localizes the nonlocal elements at least during the transition through the holes (this is also the case in transitioning particles, spin-1 included, seen in Stern-Gerlach experimental results, or during transition through the inhomogeneous magnetic volume of the Stern-Gerlach segment. In other words, if nonlocal elements have a real affect on the particle, there must be a local-nonlocal interface appearing under certain conditions at some instant of time(s).
Geistkiesel

Dearest Cangus,

I must say, it’s really too bad you don’t engage in any of these "pointless arguments." Who knows, you might actually learn something. Although, I guess the use of a baseball analogy is a sure bet when someone throws the book at you.

Point. Set. Match.

ps. http://en.wikipedia.org/wiki/Tennis :)

If anyone is interested and has any idea of where to find a Physics 101 textbook, they might find a page or two that describes wave-particle duality.
Try Feynman's 'Lectures on Physics" Vol III frimarily. The books are in the range of $65, so a library would be a good first look. Chapter one Vol Ill RF starts with some very basic stuff.
Geistkiesel

chirality:

Cangus it is spelled not.

CANGAS correct it is.

Too difficult for you it is?

PS: You are apparently deliberately misrepresenting my statement to you. Not a surprise. I was speaking of your specific attempted arguement as being obviously pointless. What is it that you are so hot to teach me?

CANGUS, I had no problem understanding PhysMachine's posts. Why do you? Suppose
you tell us which state of the electron passes through both slits, the wave function
or the particle.

Now for a question I have. If a single electron is emitted towards two open slits and
measurements are taken behind each of the slits simultaneously, how many electrons
will be measured? ONE, correct? Behind only one of the slits, correct?
2inq, excuse the buttinsky, as your question was directed elsewhere, but your question points to a tragic failure in quantum mechanical theory.

By using an ad hoc wave-particle model the problem of how one electron passes through two holes was put to rest. You are correct, measuring both holes after trasmission of the electron, only one hole will be found to have been used. Therefore, the wave nature of the electron does not provide a rational explanation.

When we look at the probelm, what must be a rational conclusion? Who a rational conslusion be that: there are elements, attributes of the electron that are not are not observed, or have remained unobserved that are, however an intrinsic part of the electron? What could be the nature of these unobserved elements, that while unobserved (or to rephrase: nonlocal) are however critical an d intrinsic elements of the electron structure.

What experoimental results is there , beside the two-hole diffraction results that might cast some light?

In Stern-Gerlach transition experiments a spin-1/2 particle, such as the electron, will, upon entering the inhomogeneopus magnetic field oriented floor to ceiling (bottom to top, - to +), will develop either a + or - component along the z-axis (down to up). Spin-1 particles will exhibit the same characteristics, with an added third trajectory as a possibility, of continuing in a more or less straight line trajectory.

The characteristics are not seen in other asepcts of the structure of the particles.
Another generalized example: A transition of the state of a particle, perhaps the electron, goes as : S -> T -> S. The particle enters the Stern-Gerlach segment as an S state particle, is changed into one of an allowed states , T, in the T segment, and upon leaving reverts, reforms, back into the 0original state S. S is generic and could be +S or -S, T can be +T or -T.

From the S-> T -> S we can see that there must be some retained information in the T state that is drawn upon by the particle when exiting the field in the T segment, otherwise it would have remained in the T state, or have evovled into another state.

The elements that guarantee the result of the T -> S transition are nonlocal (uniobserved) elements that guarantee the existence of the S state, the elements are "existence critical". No nonlocal elemenst associated with the observed state, no observed state.

RTge 2 slit experiment is directly analogous to the Stern-Gerlach transition experiments. LIke the ideal inhomogeneous magnetic field (fields with a magnetic gradient) of the SG apparatus, the charge distribution of the electron impinging on the surface of the material with the holes creates such a magnetic environment that the nonlocal elements areforced into an observed arrangeent. It is this characteristic of the electron that takes the other hole, when available, while the observed charactyeristics of the electron take the other hole.

In the Stern_Gerlach experiments the difference between a +S and +T state is simple. The +S state is the orientation of the particle magnetic spin vector, that when properly polarized in an S segment arranges the magnetic spin vector in an "up" orientation" wrt the lab frame of the SG S segment. The T segment is rotated a few degrees around the axis of travel and while the paritcles are inside the T segment the magnetic spin vector is orient to the "up" direction wrt the T frame. When exiting the nonlocal elements are instrumental in remembering the previous spin state as "up" wrt the lab frame and hence reformation of the original state is completed.

When se see that the use of one vs two holes drastically affects the distribution of the electrons on the cintillation screen we see a level of comleexity that is shrouded in mystery by the dreadful limitations imposed by quanmtum mechanical theory in describing the nature of the electron.

2inquisitive:

Do you have a standard English language dictionary?

And, do you have a grade school education, enabling you to execute at least a minimal amount of effective reading and writing?

If so, you might discern the difference between "understand" and "agreeing".

I sometimes am able to read between the lines of Physics Monkey's garbled and ultra-generalized statements and UNDERSTAND them. AGREEING with them can be something else.

If you think you never have any trouble understanding them, you are very easily amused.

Your silly questions can be easily answered in many books easily available to anyone with even modest reading skills. Are you delusional enough to halucinate that I am, or, desire to be, your personal free physics tutor?

Helpful hint: no.

If you think you never have any trouble agreeing with them, you just don't yet know and/or understand enough mainstream physics.

post by PhysMachine:



Well, OP, basically here's all there is to it. Particles behave more like waves than localized objects, and waves can interfere with each other. If you measure which slit the "particle" went through, then the particle will begin totally localize and disperse from that one slit as if it's the only source. If you don't do this, then in passing through each slit the waves will interfere like light does. You can observe this effect experimentally, too
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Phys

Your garbled syntax belies veracity in your attempts to explain Quantum Physics.

It is important to note that since not everyone is a Pulitzer Prize grade writer, anyone can write badly, not just you. My reaction to your garbled syntax is because it leaves me unable to understand what you are trying to communicate. This causes me to conclude that you may be totally incorrect, scientifically.

You seem to have told us both that an electron really does NOT, and also, that an electron really DOES travel through both slits.

If you do know which case is true according to currently accepted QP, why don't you clarify for us now, in clear grammar, if possible?


================================================== ====
by CANGAS:
"2inquisitive:

Do you have a standard English language dictionary?

And, do you have a grade school education, enabling you to execute at least a minimal amount of effective reading and writing?

If so, you might discern the difference between "understand" and "agreeing".

I sometimes am able to read between the lines of Physics Monkey's garbled and ultra-generalized statements and UNDERSTAND them. AGREEING with them can be something else."
================================================== ====

CANGAS, you seem to be unable to UNDERSTAND PM's post. Or, would you like to point out what you disagree with?

Now, CANGAS, suppose you show where "I" lack the ability to discern the difference between "understand" and "agreeing". Do you, CANGAS, state that electrons lack the wavelike state? Or do you, CANGAS, state that electrons lack the particle-like state?

Also, CANGAS, tell us what state potassium atoms (fermions) are in when cooled to 150 nanoKelvin above absolute zero. Are they still 'particles'? Are they still fermions or are they bosons? You are the acknowledged expert, correct?

2inquisitive,

You have accidentally misquoted me, it was PhysMachine who actually made the post that you quote.

My apologies, Physics Monkey. The post I was referring to was by PhysMachine, the one in which CANGAS responded to before you posted on this thread. It seems CANGAS accused both you and PhysMachine of garbled syntax. I will edit my post.