Wave function collapse for Schrödinger's cat

GW Leibniz
Messages
7
Reaction score
0
I have what is probably a very basic question about the Schrödinger's cat thought experiment. As I understand it, in order for the counter tube to break and release the deadly poison, the Geiger counter must measure whether or not an atom decays. So, why doesn't that measurement collapse the wave function? And, if that measurement isn't enough, why wouldn't the cat's observation of poison or no poison collapse the wave function?

And if I'm incorrect about the Geiger counter being a measurement, then would I be correct to assume that by the same logic, if you conducted a double slit experiment, and you put photon detectors by both slits, but you never actually look at the wall on the other side, that Schrödinger would suggest that the photon detectors by themselves were insufficient to collapse the wave function?

I get that Schrödinger used this thought experiment as a reductio ad absurdum, but I don't understand why the Copenhagen interpretation would require the cat to be in some undead quantum state.
 
Physics news on Phys.org
The point of this representation is to look past the two possible results of the experiment (Observed and unobserved) and realize what the true "Quantum Reality" is. The results of the experiment differ based on the circumstances but the statement that the cat is both alive and dead is true before the experiment actually happens.
 
GW Leibniz said:
I have what is probably a very basic question about the Schrödinger's cat thought experiment. As I understand it, in order for the counter tube to break and release the deadly poison, the Geiger counter must measure whether or not an atom decays. So, why doesn't that measurement collapse the wave function? And, if that measurement isn't enough, why wouldn't the cat's observation of poison or no poison collapse the wave function?
We are not sure what constitutes a measurement, at least yet.

And if I'm incorrect about the Geiger counter being a measurement, then would I be correct to assume that by the same logic, if you conducted a double slit experiment, and you put photon detectors by both slits, but you never actually look at the wall on the other side, that Schrödinger would suggest that the photon detectors by themselves were insufficient to collapse the wave function?
All that happens is the photon becomes entangled with the photon detectors, therefore continuing to predict a superposition of left and right slit.
 
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
I am reading WHAT IS A QUANTUM FIELD THEORY?" A First Introduction for Mathematicians. The author states (2.4 Finite versus Continuous Models) that the use of continuity causes the infinities in QFT: 'Mathematicians are trained to think of physical space as R3. But our continuous model of physical space as R3 is of course an idealization, both at the scale of the very large and at the scale of the very small. This idealization has proved to be very powerful, but in the case of Quantum...
Back
Top