Can an electron be in two places at the same time?

[OnlyMe]

The fact science is telling us matter behaves at the fundamental level like pointlike particles is all the evidence I require to state that a wave function will collapse to a pointlike system. That is just how it works.

When you have figured a precise mathematical way to express classical terms for an electron in a way that reconciles quantum field theory, then I will apologize and hand you a certificate.

I have, I think a problem with this...

It is certain that the theory does describe the colapse as a point like particle, but does that prove a dimensionless point like particle? We really have no way to measure directly anything at those scales. All of our measurements are statistical and based on a model that begins by describing the colapse as a point like particle. Thus that is the way the data winds up being interpreted.

I cannot see how if what you are suggesting, is a truely dimensionless point, that there could be either energy or mass associated with it. It becomes essentially mathematical abstraction.

Accepting the the math works out that way and stipulating that the mathimatically model is a very successful predictive tool, are you saying that in fact the particle aspect or nature of a subatomic particle, once the wave function has collapsed, is a dimensionless point?

 

[Reiku]

I have, I think a problem with this...

It is certain that the theory does describe the colapse as a point like particle, but does that prove a dimensionless point like particle?

Actually no. You are making the same mistake as the last poster. I never said this. I said experimentation varifies that electrons and other particles behave as though pointlike. By default, this must mean a collapse in the wave function must reduce to the same statistics.

 

[Reiku]

There is evidence a particle's wave will collapse to a point, if all experimental evidence suggests that particle behaves like a pointlike system.

This is what I said to Magneto. Now do you still think that is what I implied above?

 

[OnlyMe]

Actually no. You are making the same mistake as the last poster. I never said this. I said experimentation varifies that electrons and other particles behave as though pointlike. By default, this must mean a collapse in the wave function must reduce to the same statistics.

That's what I understood. I think sometimes in the back and forth I lose track.

 

[Reiku]

That's what I understood. I think sometimes in the back and forth I lose track.

It's ok. We all do at times.

 

[Reiku]

Electrons are both particles and waves, due to the wave-particle nature of matter. An interesting conceptual consideration is say we had two electrons, in relative motion, such that their waves were to cancel. The crests of one waves cancels the valleys of the other. Since the two waves cancel, would this disrupt the particle-wave duality, since all that remains will be two particles but no waves?

Particles act also as observers on other particles. Two particle's can come very close. Before any observation is made on the system, let us say that two particles have both spin up and spin down simultaneously. Two particles which come arbitrarily close can interfere with each other so that they can define either a spin up or a spin down for each particle. This natural occurance in nature is called decoherence.

 

[river]

therefore an electron cannot be at two places at once or at the same time

 

[Reiku]

therefore an electron cannot be at two places at once or at the same time

Statistically-speaking, quantum field theory predicts they can.

 

[AlphaNumeric]

Statistically-speaking, quantum field theory predicts they can.

Justify your claim with actual rigorous field theory because I don't believe you.

 

[Reiku]

Justify your claim with actual rigorous field theory because I don't believe you.

Depends on interpretation of the superpositioning principle. I thought you would have agreed with my statement, do you really want me to write up on it?

 

[Reiku]

In fact, I wouldn't need to write anything complicated. Let us say, for simplicity that

$$|\psi> = \frac{1}{2}i|A>+\frac{1}{2}i|B>$$

The physical interpretation (of course not all physicists agree with the physical interpretation), is that statistically-speaking this particle described by the state $$|\psi>$$ is one half in position $$A$$ and one half in position $$B$$.

 

[Reiku]

It has taken the best of an hour to find this link http://www.newscientist.com/article/dn18669-first-quantum-effects-seen-in-visible-object.html - this experiment kinda gives tantamount evidence that quantum superpositioning is a real physical effect.

 

[AlphaNumeric]

Depends on interpretation of the superpositioning principle. I thought you would have agreed with my statement, do you really want me to write up on it?

I'm well aware of the superposition principle. That doesn't mean the particle is in two places at once. Nor is it a necessarily field theoretic concept, it's in non-relativistic quantum mechanics too.

 

[Reiku]

Please read the link. The link is evidence of a physical interpretation of the superpositioning principle.

 

[prometheus]

In fact, I wouldn't need to write anything complicated. Let us say, for simplicity that

$$|\psi> = \frac{1}{2}i|A>+\frac{1}{2}i|B>$$

The physical interpretation (of course not all physicists agree with the physical interpretation), is that statistically-speaking this particle described by the state $$|\psi>$$ is one half in position $$A$$ and one half in position $$B$$.

I think you mean $$| \psi\rangle = \frac{i}{\sqrt{2}}|A\rangle+\frac{i}{\sqrt{2}}|B \rangle $$ otherwise $$\langle \psi | \psi \rangle \neq 1$$

 

[Reiku]

I think you mean $$| \psi\rangle = \frac{i}{\sqrt{2}}|A\rangle+\frac{i}{\sqrt{2}}|B \rangle $$ otherwise $$\langle \psi | \psi \rangle \neq 1$$

Thanks.

 

[river]

Mister from your link

Bridge between worlds

Proving that all objects, whatever their size, obeys the same rules has long been a goal of physicists. But with quantum mechanics it is no trivial matter: the larger an object, the more easily its fragile quantum state is destroyed by the disruptive influence of the world around it. O'Connell's experiments required delicate control and a temperature of just 25 millikelvin to measure the state in the few nanoseconds before it was broken down by disruptive influences from outside.

of course , thats the thing , the macro is the order of quantum , doesn't surprise me

hence why we don't get galaxies , planets etc popping in and out in the macro world ( Universe )

 

[HEXiT]

Before providing an alternate prespective, let me say that I do believe that electrons exhibit both wave and particles characteristics.

That said, above you suggest that there could be no other explanation, for a two slit experiment with electrons, resulting in an interference pattern. To that I offer the following, not as a diffinitive example, only as a alternate.

Electrons are charged particles and every thing that we have to construct the experiment is composed of "charged" materials. Assume for now that the two slits are exactly that two openings in an otherwise medium impenetrable by electrons. An electron will be far smaller than an individual slit and since both the electron and the material the slit is composed of are charged, as an electron passes through a slit its trajectory will be affected by the proximity of the material. Since the material is composed of atoms and atoms interact with electrons in discrete units, the deflection of an electron as it passes through a slit must occur in predictable patterns. Those patterns might result in the detection of the electrons after they have passed trough a double slit experiment in a pattern very much like an interference pattern. Still each electron is recorded as an independent event with only one point of detection. The interference pattern is only observed when evaluating the pattern that evolves from many detected electron's.

The answers we get in experiments like this are very often dependent upon the models we begin with. If we think of an electron as a wave, an interference pattern is a logical conclusion. If we begin thinking of an electron as a charged particle, the interaction of that charge and the material of the "slit(s)", becomes an additional variable in arriving at a conclusion.

The electron charge itself must interact with the materials the experiment is constructed from and cannot be completely eliminated from the results.

In the above I am not attempting to say this is what happens, only that there is more involved than at first appears. The particle and charge characteristics of an electron cannot be separated from its wave character. And how we interpret things that happen at quantum scales is heavily influenced by the models and theories from which we begin.

ah waves and particles??? how do you get a particle to look like a wave? well you have it travel in a spiral. from the front it will look like a particle, but side on it looks like a wave. it will then take on both properties of waves and particles.
it may be, if particles travel in pairs rotating round each other, but to the outside observer they would look like there traveling in straight lines but the reality is they may not be. they may be traveling a double helix but because the oscillation is so small we havent picked it up yet.

i have no proof of this as its just an idea i have been mulling over.