3 ms·

In Schrodinger's Cat Paradox isn't the cat itself an observer? It has eyes, therefore it would observe the poison and be dead.

wongarsu 6y ago
If the cat is an observer, then is the bottle of poison also an observer? Are the cells of the cat? Are the atoms of those cells? What is it that gives the cat observer status? The intent of the thought experiment was to show that the Kopenhagen Interpretation of quantum physics is ridiculous. In the many-worlds interpretation for example there is no paradox, as time goes on more and more worlds exist where the cat died at some point.
- cloudking 6y ago
  Going off the double slit experiment, it seems the definition of an observer is something that can take in light, interpret and measure it. The examples given are eyes and cameras. (I'm not claiming I understand this, just trying to)
  - Green_man 6y ago
    "observation" isn't important, it's enough interaction to decohere the superposition, or in another sense, entangle it with the environment. A polarization filter could be considered an "observer" in some sense, but I think focusing on observation results in a less clear and truthful understanding of what a measurement is. A polarization filter rather interacts with the light in a strong enough way to force conditional behavior based on its polarization. This results in photos that have a superposition of different polarizations to probabilistically become one of the polarizations, wrt the respective amplitudes of each polarization for that photon.
  - wongarsu 6y ago
    The double slit experiment works with much more than just light. It works just as well with electrons, and even with large molecules (the current record seem to be molecules of 2000 atoms each) [1]. That gives you a pretty wide range of observers under your definition. 1: https://en.wikipedia.org/wiki/Double-slit_experiment#Other_variations https://en.wikipedia.org/wiki/Double-slit_experiment#Other_v...
- wruza 6y ago
  Looking for a solution of f(x)=1/x at x=0 is also ridiculous, because it is simply not defined there. But how does then a quantum cat in a box pass this test? Is a completely coherent box of cat and poison that could kill it before decoherence even possible? Quantum computers have to freeze everything to absolute zero+ to work without decoherence, but wouldn't that, applied to the box, actually save the cat (or kill it, depending on your viewpoint)? Poison couldn't do its job at zero kelvin. And you cannot have a normal temperature catbox that doesn't decohere immediately, unless it is a box of startrek quantum force shields. Yes, at zero temps we can claim anyway that process maybe has been started, but then when we look at it (by unfreezing), we actually begin to observe that one radioactive atom in our, unseparated reality, as if nothing happened before we opened a lid. I'm likely wrong in details here, but isn't that thought experiment similar to "what happens at the origin when we draw a hyperbola" sort of question? (Nothing happens, as you can't draw a complete hyperbola.)

wongarsu 6y ago

If the cat is an observer, then is the bottle of poison also an observer? Are the cells of the cat? Are the atoms of those cells? What is it that gives the cat observer status? The intent of the thought experiment was to show that the Kopenhagen Interpretation of quantum physics is ridiculous. In the many-worlds interpretation for example there is no paradox, as time goes on more and more worlds exist where the cat died at some point.

cloudking 6y ago
Going off the double slit experiment, it seems the definition of an observer is something that can take in light, interpret and measure it. The examples given are eyes and cameras. (I'm not claiming I understand this, just trying to)
- Green_man 6y ago
  "observation" isn't important, it's enough interaction to decohere the superposition, or in another sense, entangle it with the environment. A polarization filter could be considered an "observer" in some sense, but I think focusing on observation results in a less clear and truthful understanding of what a measurement is. A polarization filter rather interacts with the light in a strong enough way to force conditional behavior based on its polarization. This results in photos that have a superposition of different polarizations to probabilistically become one of the polarizations, wrt the respective amplitudes of each polarization for that photon.
- wongarsu 6y ago
  The double slit experiment works with much more than just light. It works just as well with electrons, and even with large molecules (the current record seem to be molecules of 2000 atoms each) [1]. That gives you a pretty wide range of observers under your definition. 1: https://en.wikipedia.org/wiki/Double-slit_experiment#Other_variations https://en.wikipedia.org/wiki/Double-slit_experiment#Other_v...
wruza 6y ago
Looking for a solution of f(x)=1/x at x=0 is also ridiculous, because it is simply not defined there. But how does then a quantum cat in a box pass this test? Is a completely coherent box of cat and poison that could kill it before decoherence even possible? Quantum computers have to freeze everything to absolute zero+ to work without decoherence, but wouldn't that, applied to the box, actually save the cat (or kill it, depending on your viewpoint)? Poison couldn't do its job at zero kelvin. And you cannot have a normal temperature catbox that doesn't decohere immediately, unless it is a box of startrek quantum force shields. Yes, at zero temps we can claim anyway that process maybe has been started, but then when we look at it (by unfreezing), we actually begin to observe that one radioactive atom in our, unseparated reality, as if nothing happened before we opened a lid. I'm likely wrong in details here, but isn't that thought experiment similar to "what happens at the origin when we draw a hyperbola" sort of question? (Nothing happens, as you can't draw a complete hyperbola.)