Heisenberg Uncertainty Principal does not show indeterminism

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Thanks. I will have to spend a lot of time researching all your points above.

I hope someone argues the other side.

The Bohr model of the hydrogen atom has the (bound) electron zipping around the nucleus at about 2 million meters/sec ( source, http://c2.com/cgi/wiki?SpeedOfElectrons )

HEISENBERG is still feeling comfortable

God, I hate maths.

Oh yeah well then try this,

Take some electron emitter, and a very narrow tube and have the ray pass through a magnetic field, the field will bend and then at the other end, have a plate that illuminates when an electron hits it, then put a video camera on that plate. The instant that electron hits the plate, you will be able to know the velocity (and thus momentum) of the particle by its deflection in the magnetic field, and you will know its position the instant it hit the plate. There what happens when you do that?

^ Magnetic fields have/cause other uncertainty relationships. I.e. the classical center of the orbit of a particle in a magnetic field can't be determined perfectly in the x direction and y direction at the same time. So, the narrower the tube (delta y), the less well you know the point at which the particle hits the screen (delta x). IOW, the smaller you make the tube the greater the scatter you're going to see in the indication of the momentum on the screen.

The link below shows that, though it's a bit hard core. (Is a rigorous example of how classical physics equations are quantized for those interested in that.)

http://galileo.phys.virginia.edu/classe ... cField.htm

Then publish your findings and put them up for peer review. Otherwise you are just another internet expert.

I'll let you know that the paper he linked to is a hoax, before you waste your time in it.
Also, position and momentum are not the only variables related by the HUP.
http://en.wikipedia.org/wiki/Conjugate_variables

It is a creative idea. However ...

1. First, linear momentum is a vector quantity, possessing a direction as well as a magnitude. It is the directional vector of the momentum that is uncertain in the Uncertainty Principal.

2. It would not appear possible to compute the momentum of the electron above. We can see the impact point on the plate, but how to geometrically compute the trajectory of how it reached that point ?

Because the light being used for the camera - that is being shined on the plate - would impact some momentum to the electron. Thus, just like the Uncertainty Principal experiment, the light interferes with the directional vector of the electron.

This is shown below in the figure as the theta angle. The delta x is a known location, so we know the electron is within delta x. However, the theta angle is unknown because the gamma wave "green arrow" imparted some momentum to the electron "red arrow" as it enters the observation device.

Simply, the Uncertainty principal means that if you shorten delta x, then the light is more diffusive "fans out", and thus, the precision of the directional vector of the momentum is known less precisely.

That is -speed- not velocity. Velocity is a vector quantity. Let v(t) be the value of a vector at time t.

Now consider a particular instant t0. The velocity at time t0 is limit h ->0 (v(t0 +h) - v(t0))/h This is a vector, not a scalar.

that is the velocity at t = t0.

ruveyn

How close can you get to knowing both things, for instance, say at 10 milliseconds you can know the momentum nearly exact, would it take more than a milisecond to know the position nearly exact? Is there a delay between getting information of one kind and then the other kind? how narrowly can you know both things?

Also, suppose that you can know the position of the electron close to exact at time T1, then a short time later you try to find the momentum, is the degree you can know the momentum equivalent to the inverse of the degree you know the position based upon the distance c(dT) where c is the speed of light? That would answer my question if that's the case.

Wait a second, i meant to say c/dt not c*dt I just thought of something, what if you had the previous case, where you know the momentum, and not the position, and then the position and not the momentum. If it's symmetrical then you have the same time constraints right? so the degree you know one from the other is. I understand the case of knowing position and not knowing momentum, but I don't understand it the other way around other than, my intuition seems it would be symmetrical.

It feels like space-time, like it should be one quantity or something like the particle's 'pomentum'.

Wait a second, i meant to say c/dt not c*dt I just thought of something, what if you had the previous case, where you know the momentum, and not the position, and then the position and not the momentum. If it's symmetrical then you have the same time constraints right? so the degree you know one from the other is. I understand the case of knowing position and not knowing momentum, but I don't understand it the other way around other than, my intuition seems it would be symmetrical.

It feels like space-time, like it should be one quantity or something like the particle's 'pomentum'.

It is easier to look at the above drawing to see what is happening.

First, it is not that one is unknown. Both are always known.

What changes is that when you know one more precisely, then you know the other less precisely.

And as was stated above, this also consequently applies to relational conjugate variables ( http://en.wikipedia.org/wiki/Conjugate_variables ).

First, it is best to understand in terms of position and directional vector of the momentum.

Looking at the figure ..

Case 1: The position is known more precisely, thus, the momentum is known less precisely

The delta x is shorted and that causes the cone to widen i.e., "fan out" more based on the diffusion of light. This causes the theta angle to increase, thus, the directional vector component of the momentum becomes less precisely known.

Case 2: The momentum is known more precisely, thus, the position is know less precisely

The delta x is lengthened and that causes the cone to become less "fanned out" based on the diffusion of light. This causes the theta angle to decrease, thus, the directional vector component of the momentum becomes more precisely known.

Looking at the figure ..

Image we know one of them precisely ...

Case 1:
Assume we know the position precisely. This means delta x= the size of the electron. That means the cone is fanned out the maximum and the theta angle is the maximum. So, we know the directional momentum vector the least precisely because it could be anywhere in the cone and in this case the cone is widened to the maximum.

Case 2:
Assume we know the momentum precisely. This means the black lines on the side in the figure above are pushed outward on the bottom, and become closer on top. This means the theta angle is minimal.

We know the directional momentum vector more precisely because the cone is not as wide and less diffusion can happen.

Further ...

Problem 1 – If the photon has a short wavelength, and therefore, a large momentum, the position can be measured accurately. But the photon scatters in a random direction, transferring a large and uncertain amount of momentum to the electron. If the photon has a long wavelength and low momentum, the collision does not disturb the electron's momentum very much, but the scattering will reveal its position only vaguely

.Problem 2 – If a large aperture is used for the microscope, the electron's location can be well resolved (see Rayleigh criterion); but by the principle of conservation of momentum, the transverse momentum of the incoming photon and hence, the new momentum of the electron resolves poorly. If a small aperture is used, the accuracy of both resolutions is the other way around.
The combination of these trade-offs imply that no matter what photon wavelength and aperture size are used, the product of the uncertainty in measured position and measured momentum is greater than or equal to a lower limit, which is (up to a small numerical factor) equal to Planck's constant.[58] Heisenberg did not care to formulate the uncertainty principle as an exact limit (which is elaborated below), and preferred to use it instead, as a heuristic quantitative statement, correct up to small numerical factors, which makes the radically new noncommutativity of quantum mechanics inevitable.

http://en.wikipedia.org/wiki/Uncertainty_principle

LoveNotHate, by any chance does this thread have anything to do with that discussion we had in the earlier thread?

In any case, that fact that there is a fundamental limit to how precisely one can measure both quantities is the reason why it's not deterministic. Yes, both quantities can be known to a degree but to the extent where they are unknown, there is a range of possible values and within this range, the exact motion is deterministic.

Yes, I did a few weeks of research.

1. I posed the same question, whether the Uncertainty Principal alone proves indeterminism in the universe? I fail to see it. I read online physics forums, and physics youtube videos, and no one seems to confront this issue. They seem to rely on the so called "collapse of the wave function" as the means to argue for universal non-determinism, not technically the Uncertainty Principal.

2. As you can see in my original post, in the video, the physicist states: "Einstein was wrong. The Uncertainty Principal shows the universe is non-deterministic". However, in physics , the Uncertainty Principal is not about the so called"wave function collapse". So, this physicist is arguing merely from the Uncertainty Principal that non-determinism is proven. note: I did not want to address the myriad of so called"wave function collapse" implications in this thread.

3. The "uncertainty" is because of the observation method being used. "Uncertainty" is created based on the light wave that is being used as an observer (shown as gamma wavelength lambda in the figure) . This wave imparts an unknown momentum to the electron, and when the light diffuses into the observation device, then the precision of the momentum becomes more or less precisely know based on changing the delta x position of the electron.

If delta x is shorter i.e., "position is more precisely known", then the cone is wider and light is more diffusive, thus, the theta angle is greater, and the directional vector of the momentum and consequently the momentum is less precisely known.

If delta x is longer i.e., "position is less precisely known", then the cone is not as wide, and light is less diffusive, thus, the theta angle is lesser, and the directional vector of the momentum and consequently the momentum is more precisely known.

4. Thus, the Uncertainty experiment creates this "uncertainty" ? The introduction of the gamma wave, as the perhaps the best observation means is the cause of the uncertainty.

5. At best, the Heisenberg Uncertainty Principal tells us that based on present observation means, there is this uncertainty relationship between the precision in measurement between the position and momentum of a particle?

6. My other problem with the Uncertainty Principal is the mathematical proof ( http://www.tjhsst.edu/~2011akessler/notes/hup.pdf ). They assume the probability distribution for momentum i.e., the "proof" assumes uncertainty . Well, of course, the resultant equation shows uncertainty, it is because they make that assumption in the "proof".

So, the "proof" is a back-ended description of the fundamental problem of the gamma wave imparting an unknown momentum to the electron.

7. Thus, I fail to see any evidence of indeterminism.

8. Further, the brain does not have a light inside it to create this uncertainty, presumably, thus, how can it possibly be argued that this proves free will as the physicist does ?