# The Naked Scientists Forum

### Author Topic: Can Shroedinger's cat produce kittens?  (Read 477 times)

#### Atomic-S

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##### Can Shroedinger's cat produce kittens?
« on: 13/08/2016 06:33:07 »
Most of us have heard of Shrodinger's famous cat, who, using the principle of quantum mechanics, can be both dead and alive at the same time.  This leads to the following interesting question:  Suppose we know that Shroedinger's cat is living, but neglected to measure his/her sex.  So the cat sits in the closed box in the state (|male> + |female>)/√2 .  Both states must be regarded as present, having not been observed.  However, if both are present, there is the possibility that the two states may get to schmoozing, and end up producing a litter of kittens.  So that, if we wait a while, then open the box, we might observe not only the cat, but also kittens too.  Except that a cat upon being observed cannot have any sex other than male or female, which are its eigenstates.  But to observe only a male cat, or only a female cat, along with kittens, would violate the laws of biology, and therefore is not a permissible outcome.  So the conclusion would be that no, Shroedinger's cat cannot produce kittens even if it is in an indefinite sexual state.

Except that there may be a way around this problem.  If the box has a small hole that is large enough for kittens to escape but not large enough for the cat to escape, the two states of the cat can proceed merrily to produce kittens, and some of them may escape without violating the preceding restriction.  So what we would do, is set up a camera to photograph kittens as they come out, and after a long while, we would expect to see some.  However, its progenitors as a pair are only 50% present. So when any kitten exits the hole, there is only a 50% chance that it would be observed. Therefore, if we wait the length of time required for a normal pair of two cats to produce about 100 kittens, Shrodinger's cat should produce about 50 observable kittens.  Correct?

#### Blame

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##### Re: Can Shroedinger's cat produce kittens?
« Reply #1 on: 13/08/2016 07:06:07 »
Both states are NOT present. There is only one cat with only one sex. That much is already determined.

Similar with a photon. When it is emitted its destination could be anywhere in the universe. You could say that the whole universe rings like a bell till it arrives. However it is one photon and will have one destination.

#### jeffreyH

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##### Re: Can Shroedinger's cat produce kittens?
« Reply #2 on: 13/08/2016 18:40:24 »
Both states are NOT present. There is only one cat with only one sex. That much is already determined.

Similar with a photon. When it is emitted its destination could be anywhere in the universe. You could say that the whole universe rings like a bell till it arrives. However it is one photon and will have one destination.

What if instead of a cat we have a particle. The type of particle could be matter or antimatter. What is the probability of annihilation products escaping from the box?

What would this tell us about how the vacuum interacts with mass?

#### PhysBang

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##### Re: Can Shroedinger's cat produce kittens?
« Reply #3 on: 13/08/2016 19:20:33 »
Most of us have heard of Shrodinger's famous cat, who, using the principle of quantum mechanics, can be both dead and alive at the same time.  This leads to the following interesting question:  Suppose we know that Shroedinger's cat is living, but neglected to measure his/her sex.  So the cat sits in the closed box in the state (|male> + |female>)/√2 .
No the statistics are probably roughly 50/50, since we we don't need quantum probabilities to represent the sex of a mammal.

#### Blame

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##### Re: Can Shroedinger's cat produce kittens?
« Reply #4 on: 13/08/2016 20:32:30 »

What if instead of a cat we have a particle. The type of particle could be matter or antimatter. What is the probability of annihilation products escaping from the box?

What would this tell us about how the vacuum interacts with mass?

It doesn't matter how you re-phrase the question. One particle is one particle and if you have already determined that you only put one in then the NUMBER is not indeterminate. Also the nature of the particle has already been determined to be matter or antimatter - you don't need to look in the box to know that. Nether of those will go pop on their own.

I think that this is all about misunderstanding the word "indeterminate". As used it means "not able to determine between a fixed set of possibilities" NOT "any outcome is possible". None of possibilities leads to bangs or kittens.

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##### Re: Can Shroedinger's cat produce kittens?
« Reply #4 on: 13/08/2016 20:32:30 »