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The question may seem stupid but I have heard from doubtful sources that the Heisenberg uncertainty principle results from the observer effect. I don't understand however how this works and i'm now confused on the semantics of both terms and if they have any links between them.

From my understanding the uncertainty principle comes from the wave nature of particles which limits the precision we can have between position and movement.

And the observer effect was the collapse of the probability wave function of a particle when it is observed to appear like a particle.

EDIT : Is Heisenberg's uncertainty principle due to the wave function collapse ?

mael Delaunay
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The "observer effect" as you put it can be thought of as the plain fact that in Quantum Mechanics observations do not commute. This is a physical fact that has many different interpretations (Copenhagen, Many Worlds, etc.) but it is a starting point for our Theory of Quantum Mechanics.

So before any discussion of waves, Fourier Transforms or even physical situations let us consider observations in Quantum Mechanics generally by some operators that do not necessarily commute. That is to say $[A,B]=AB-BA \neq 0$

We find using basic algebra:

$$\sigma_A \sigma_B = \frac{1}{2}\Big|\big\langle [A,B] \big\rangle\Big|$$

If you're interested in the derivation see here: https://www.youtube.com/watch?v=qgkWUuqoSVM

We see that the uncertainty product between two observables is directly proportional to the absolute value of the expected value of their commutator; and so observables which do not commute MUST posses an uncertainty relation; weather that observable is position, energy, spin, whatever.

And so yes the "observer effect" which is the physical fact that observations do not commute in Quantum Mechanics implies uncertainty relations.

xXx_69_SWAG_69_xXx
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The “observer effect” results from the interaction of a quantum system with a measurement device (though the term observer seems to imply that you need a conscious person for this effect, which is not true and sometimes causes confusion). The uncertainty principle is more fundamental and results from the fact that certain quantum measurements cannot be made simultaneously, or equivalently, certain quantum observables do not commute, most famously, position and momentum. Thus it is inaccurate to say that the Heisenberg uncertainty principle results from the observer effect. They are both results of quantum theory that are related via the theory instead one being the result of another.

The HUP is perhaps the most fundamental result of quantum theory.

joseph h
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