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Schrodinger's Cat- Cat variations causing loopholes in the paradox?

  1. Jul 13, 2012 #1
    So, we probably all know by now the Schrodinger's cat thought experiment. A cat is in a box with a small amount of radioactive material. If it happens to give off radiation, it sets off a geiger meter, which causes a hammer to break a small vial of poison gas. Until you look in the box, the cat is either alive or dead. As simple as it seems, there are many layers to the experiment. To start, imagine you remove the cat. Then, it's a matter of wether or not the poison gas vial breaks. The only variable in the experiment that randomizes the glass breaking would be the radioactive material. It is also believed that subatomic particles concealed within the radioactive material can take on different choices. Different options in whatever happens. For example, you throw a rock at a board and it falls over. Any subatomic particles in that board would continue to fall to the ground, yet at the same time stay in the same spot. And fall to the other side. They would do whatever you decided to do, and what you could've done. So, the radioactive material and it's subatomic particles continue on both paths, giving off radiation, and not giving off radiation at the same time. Now, put the cat back in the box. You know the cat is either alive or dead, yet it can't be both. Now, look at it this way- the cat can only either perceive the glass break and die, or not perceive it and live. There's no not perceiving it breaking and dying or perceiving it breaking and not dying. It's one or the other, and some random physics equation is taking place as soon as we look in, choosing wether or not the cat died. So, according to all that, if you were to get a cat that could have no perception of the event- a cat with a horrible brain disorder- it could not perceive the vial break and die. It's not entangled in that equation any more. With no perception of the event, it would all be up to the radioactive material, which is doing both things it could be doing at the same time. And without that equation taking place when we look in, you're almost just looking in for the shards of glass. The cat is a Newtonian object. It follows the laws of physics. It's not a subatomic particle, which can do both things it could be doing at the same time. It's either alive or dead, yet the radioactive material is doing both. If the cat isn't in that equation, when you look in, would that force the subatomic particles to choose the path of not giving off radiation every time?
  2. jcsd
  3. Jul 13, 2012 #2


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    Welcome to PhysicsForums, Drake!

    Whether the cat is conscious or not does not really change anything. The cat as observer does not affect the emission of radiation.
  4. Jul 13, 2012 #3
    The point of this thought experiment is that the cat isn't just alive or dead, but is in fact both alive and dead at the same time. What the cat perceives is irrelevant.
  5. Jul 13, 2012 #4
    This paradox has always been confusing because cats have an additional degree of freedom which comprises a significant condition on the experimental outcome... the experimenter would need to know how many of a particular cat's nine lives have been expended prior to entering the box. The experimental paradox would only attach if the cat is on his ninth life, but neither the experimenter nor the cat can know this, it is called a hidden variable.
  6. Jul 17, 2012 #5
    The cat's hypothetical "consciousness" is not a sufficient observer to make a determination of whether the material has decayed or not, for the same reason that the double slit diffraction pattern wont collapse simply by having an experimenter look at the apparatus. What WILL "collapse the wavefunction" is a measurement by the Geiger counter. From that point on, the system is classical and deterministic. The cat cannot be both alive and dead, because for the cat to have been killed by the poison, even in part of a hypothetical superposition of live and dead states, an accurate measurement of whether or not a particle had decayed would have had to occur.

    That's how I've always seen it. It will probably always be up to debate. (Until humankind can replace language with math :wink: )
  7. Jul 17, 2012 #6
    Too true!
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