  ## Heisenberg misunderstood the Uncertainty Principle

### Probabilities are the precondition of the Uncertainty Principle and not its effect.

We devised and analyzed both real and thought experiments that bypass the uncertainty relation, in effect, to "trick" the quantum objects under study. Nevertheless, the results always reveal that..complementarity remains intact even when the uncertainty relation takes no role.

Englert, Scully, and Walther / 1994, p56

The true world--we have abolished. What world has remained? The apparent one perhaps? But no! With the true world we have also abolished the apparent one.

Friedrich Nietzsche / Twilight of the Idols
I cannot now see any problem in the dualism of waves and particles and never could.

Light penetrates a double-slit and projects an interference pattern on a photo-screen. If one of the slits is closed, then no interference pattern is formed but there exists a certain probability of the light penetrating the open slit and a certain probability for the fact that the light strikes the covering behind the second slit.

One sees that here the light corresponds to a certain probability distribution to cause local density dots, a dynamic probability distribution which possesses the character of waves and is capable of interference. This is the simple stating of the empiric factual matter, thus of the phenomenon.

We cannot a priori expect from light behaviour like that of small billiard balls with a precisely defined place and known speed at every moment, just as little as we would attempt to describe snow flakes as billiard balls. We must first take the phenomenon for that which it depicts. In doing so, it turns out that light constitutes a probability distribution. Thus we accept it as such! Hypotheses non fingo.
On the other hand, I see a problem in the Copenhagen interpretation of quantum theory. That view does not take light for what it constitutes - a probability distribution.

### The Uncertainty Principle

The principle of complementarity is certainly more fundamental than is the uncertainty relation."
(Englert, Scully, and Walther / 1994, p60 ). Heisenberg’s argumentation contains a classical case of circular reasoning, confusion between cause and effect, since the probability distribution (statistic interference pattern) is the prerequisite for establishing the Uncertainty Principle.
Before going into Bohr's analysis of the uncertainty principle, two points should be made clear. First, the mathematical formalism expressing relationships encompassed by the "uncertainty principle" are straight forward deductive consequences of the quantum postulate. All too often, discussions of the principle begin with a series of thought experiments intended to demonstrate that observations which determine the value of one observable within a certain range require physical conditions which preclude determining its canonically conjugate observable within a range that would contradict the uncertainty principle.

It is then easy to get the mistaken impression that the principle expresses an empirical generalization derived from analyzing physical situations and that such a presumed empirical discovery is then injected as a postulate into the theoretical formalism. However, this is not the case. Heisenberg first developed his formalism for theoretical representation of the atomic system processes, and then showed that the consequence of his formalism was that the system could not be characterized by a state which was defined in terms of precise values for both canonically conjugate parameters.

Dan Glover ( mirror / WWW)
According to Heisenberg, quantum physics is admittedly a basic statistical element, but this is no property of nature. It is only introduced by means of interference which the physicist causes in observing nature:

In the succinct statement of the law of causality, “If we know the present precisely, we can calculate the future,” it is not the final clause which is false but the presupposition.

Since one is not able to measure with absolute precision the initial values of impulse and location, one can only calculate probabilities for location and impulse of the particle at any future moment.
According to Heisenberg, only from measurement or interference does the statistical divergence of the particle orbit follow.

Heisenberg writes:
Only when we proceed from the Schrödinger function to the physical behaviour of the system, and thus disturb the system from the outside in order to be able to observe it, then the result of the experiments can only be predicted statistically. One can always consider the interference to be the cause of the indeterminateness which the measuring equipment provokes in the system.
 Heisenberg argues as follows: 1. The shorter the waves of light with which the location of electrons is measured, the more precisely can the location be measured, but the stronger will the impulse be disturbed. 2. The longer the waves of the light with which the location of electrons is measured, the more precisely can the electron impulse be measured, since long-waved light contains less energy than short-waved light and the impulse is less disturbed. But with long-waved light the location cannot be precisely measured since it diverges statistically. 3. Impulse/location uncertainty follows from this. From that in turn there follows the statistical divergence of particle orbits. If one were actually able to conduct a precise simultaneous measurement of location or impulse, then it would be possible to exactly predetermine the particle orbit deterministically and thus to exclude statistical divergence.

Heisenberg is totally right!

With long-waved light, the exact location of a particle cannot be determined because it only appears on a photo-screen with a widely dispersed statistical pattern. The probability wave of light prevents exact measurement.

It would be otherwise if squaring the amplitude of the wave would not signify the location probability of the photon, but if light had a completely even energy distribution, such as for instance a wave of water. For then it would indeed be possible to exactly determine the location of an electron with long-waved light as well without unduly disturbing its impulse through such measurement.
Such a wave would generate a completely evenly smeared pattern of interference on a photo-screen (and not merely individual, statistically distributed density dots). Such an even interference pattern would provide such a plenty of data (namely for each individual dot of the photo-screen a completely specific energy value), since the latter could be deduced exactly from that one measurement of the electron’s location.

One thus sees: Heisenberg’s argumentation presupposes that the light wave corresponds to a probability distribution. But this is what he wanted to derive!!!

The objection, that what has been presupposed for proof is what was supposed to be proven, is the strongest objection which can be raised against an hypothesis altogether.

Formal neatness is more important than anything else. This critical point cannot be underestimated.

The statistical nature of waves prevents simultaneous precise location and impulse measure in the first place and is thus the prerequisite for establishing the Uncertainty Principle. Thus it cannot be derived from it.

The basic phenomenon is the basic probability and the Uncertainty Principle is one of its aspects.

Though it forms no part of complementarity, the disturbance principle was frequently defended as part of the Copenhagen Interpretation and often identified with Bohr's view in the years following Heisenberg's discovery. From the perspective of Heisenberg, it appeared that the basis of the disturbance principle lay in the fact that the instruments doing the observing "disturbed" the observed system such that its state after observation is no longer what was determined in the measurement.

However, the disturbance interpretation plays havoc with the facts behind the genesis of the uncertainty principle and its status within the mathematical formalism of quantum mechanics. The principle is a straight forward deductive consequence of the quantum theoretical formalism which provides a highly confirmed means of predicting the outcome of interaction between radiation and matter. There is no mention of disturbance in the derivation of the principle itself, nor of how to go about determining the relevant parameters.

The design of experiments is relevant only to interpreting the physical significance of the principle.

Dan Glover ( mirror / WWW)
Heisenberg’s achievement lay precisely in demonstrating which consequences were implied by the probability wave postulate. Heisenberg was the first to show that the statistical nature of basic probability waves could not be circumvented by a measurement of any kind, since probability waves would need to be used for this as well and which would not permit simultaneously precise location and impulse measurements.  