Is the Screen an Observer in the Double Slit Experiment?

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I am new to this field as will be apparent from my questions. I have a doubt in the basics that has been bugging me for days. This is about the original double slit experiment.

As we all know that in the experiment, there is a double slit and a screen that displays the result of a photon (say) bombardment. My confusion is that I find it hard to understand whether the screen is an observer or not. I mean, the moment we placed a screen in front of the double slit as an act to observe which slit the photon is coming from, the probability wave should have collapsed and the photon should have chosen a single slit to get through (I am focusing only on the result; not the inference).

In other words when there is no background screen, the photon will be taking both slits simultaneously; but the moment an observer steps in, which in this case is the screen, why doesn’t the wave collapse? We know that it doesn’t; so how can we conclude that an observer collapses the photon from a wave to a particle? If the screen is not an observer, why does the photon hit at only one point of the screen in case of a single slit or no slit...to hide the which-way info, why doesn't it behave as a wave.

It is apparent that I am missing something basic here. Any inputs will be appreciated.
 
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Yes, the screen is an "observer", or something that is related to an (apparent) wave function collapse. If you want to understand how the apparent collapse may take place without a true collapse, see also about the Bohm interpretation.
 
The how part was never my problem...just the what. Also, I am aware of Bohm's interpretation. Anyways, thanks for the response!
 
I read Hanbury Brown and Twiss's experiment is using one beam but split into two to test their correlation. It said the traditional correlation test were using two beams........ This confused me, sorry. All the correlation tests I learnt such as Stern-Gerlash are using one beam? (Sorry if I am wrong) I was also told traditional interferometers are concerning about amplitude but Hanbury Brown and Twiss were concerning about intensity? Isn't the square of amplitude is the intensity? Please...
I am not sure if this belongs in the biology section, but it appears more of a quantum physics question. Mike Wiest, Associate Professor of Neuroscience at Wellesley College in the US. In 2024 he published the results of an experiment on anaesthesia which purported to point to a role of quantum processes in consciousness; here is a popular exposition: https://neurosciencenews.com/quantum-process-consciousness-27624/ As my expertise in neuroscience doesn't reach up to an ant's ear...
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
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