Undergrad Heisenberg Microscope: Exploring Single Photon Diffraction

[Axel Togawa]

TL;DR

diffraction pattern generated in the thought experiment of Heisenberg

In the thought experiment proposed by Heisenberg, a single photon is scattered by the electron that we want to observe, and entering the microscope lens (the photon), it will create a diffraction pattern that gives the uncertainty on the position according to the law of optics. I wanted to ask how the single photon could create a diffraction figure?

 

[Nugatory]

I wanted to ask how the single photon could create a diffraction figure?

It can't, not if you're considering a single photon.

Threads like this are the reason Physics Forums generally encourages people to include the sources that they've using. Without knowing that, we have no way of knowing whether you've misunderstood the explanation or the explanation was bad. So if you could tell us more about your starting point, you'll get more and more helpful answers.

 

[Axel Togawa]

Yeah, sorry you are right. Anyway i found it on these sites:

http://www.bio-physics.at/wiki/index.php?title=Heisenberg's_Microscope
https://chem.libretexts.org/Bookshe...eory/Electrons_in_Atoms/Uncertainty_Principle
https://en.wikipedia.org/wiki/Uncertainty_principle#Heisenberg's_microscope

maybe i misunderstood the explanations, but i wanted to ask because in my physics lecture the use of only photon was specified to influence as little as possible the electron

 

[EPR]

A single photon will not create a diffraction pattern. Your links don't say that either.

A succession of many single photons can create a diffraction pattern.

 

[Axel Togawa]

Ok thank you fro the answer

 

[vanhees71]

You can well argue with a single photon. It's only the meaning of the diffraction pattern which changes in a "revolutionary way". The diffraction pattern is of course a "wave phenomenon", i.e., it occurs when using classical em. waves or many single photons.

The important "revolutionary" change between classical electromagnetism and quantum electrodynamics is the meaning of this diffraction pattern when considering the case of a single photon: According to the Born rule of quantum theory the diffraction pattern depicts the probability of the single photon to hit the screen at a given place. The uncertainty of the position of the electron using a single photon is due to the randomness of the position where this photon is detected, i.e., you cannot trace back in a one-to-one connection the position of the electron which scattered the photon from the place where the photon was detected.