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Schrodinger's Wife pregnant or not?

  1. Jan 6, 2004 #1
    Schrodinger's Wife.

    Let's imagine Schrodinger's wife (Monica L.) is for 24 hours in a closed medical room with the Dr. Who's AAIM (automatic artifical insimination machine). We don't know if the machine will do it's work because there is a random time-system inside that will warm-up Erwin's frozen sperm. We don't know the outcome: Is Monica pregnant or not ...? When we open the door Dr. Who can do the tests.

    Can we say that during the time we were waiting outside that Schrodinger's wife was in a half-pregnant superposition?

    So what's your idea?
  2. jcsd
  3. Jan 6, 2004 #2


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    What's different here from the cat? "Wigner's friend" at least had a consciousness inside the box to reduce (or not?) the wavefunction. But Mrs. Schroedinger herself doesn't know whether she's impregnated or not, so as an observer she's no better than the (presumably not sufficiently conscious) cat.
  4. Jan 6, 2004 #3
    There are many elements different. Death vs giving life is one.
    But what about her hormons? They know already IFF she's pregnant. She doesn't know consciously but her body knows? I think so ... a lot of hormonal activities have changed.
    A more complex point is that IFF she pregnant there is a new observer: Erwin junior.
  5. Jan 6, 2004 #4
    Condom Mechanics

    Perhaps the technology already exists to demonstrate quantum phenomena involving individual sperm cells? Suppose one isolates a single cell, and allows it to traverse, Millikan-style, a region where it can possibly interact with a weak beam of energetic particles. If the particle is energetic enough to kill the cell, then you can have a sperm cell that is in a superpostion of "dead" and "live" states...

    If the particle is scattered in the collision, will it be in an entangled state with the cell, so that a measurement on the particle will "kill" or "spare" the cell?
    Last edited: Jan 6, 2004
  6. Jan 7, 2004 #5
    Let's say my wife was in a closed room with "Bill" And, Bill has intermittent problems with ejaculation.
    A doctor is waiting outside, to test my wife for pregnancy afterwards.
    Since pregnancy during activity is indeterminate given the lack of observation, is my wife in some pseudo-state of pregnancy becuase the doctor has not yet examined her?
  7. Jan 12, 2004 #6


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    entanglement versus mixture.

    You guys confuse an entangled quantum state with a statistical mixture.
    An entangled quantum state is a NEW physical state. A statistical mixture is a description of ignorance. Einstein thought that both were equivalent but Bell showed that this is not the case (Bell's inequalities). Aspect-like experiments then confirmed this.

    In fact, the theory of decoherence shows that due to inevitable interactions with the environment, IF WE LIMIT OURSELVES TO THE OBSERVED SYSTEM, then a pure, entangled state quickly evolves into a mixture (and the entanglement is with the rest of the universe instead of just between the system states), except if we can avoid interaction.
    This then resolves the Schroedinger cat problem: although initially the cat may be in an entangled state, for, say, 10^(-50) seconds, this will extremely rapidly evolve into a local mixture, and the entanglement will be in the air molecules, the infrared photons, earth's gravity etc... and hence ununentangible for all practical purposes. The reason is that a macroscopic body such as a cat has unavoidable interactions with the environment. Pairs of photons can be protected for a while from doing so, but not a cat, or your wife.
  8. Jan 12, 2004 #7
    How about a single cell? A single chromosome? A nanomachine?
  9. Jan 12, 2004 #8


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    mesoscopic things...

    It is amazing how quickly we decohere, even for mezoscopic objects. Have a look at some estimates at:


  10. Jan 12, 2004 #9
    It is never possible to avoid interactions.

    Everything is always gravitationally connected.
    The perception of reality may be twisted if - like in many mathematical constructs - gravity is just cancelled or replaced by another value. (eg. Path integrals in non-gravitational theories). That influences the conclusions or interpretation.

    On the other hand this is an interesting link: link: http://ourworld.compuserve.com/homepages/dp5/vigier.htm [Broken]
    Interesting link to Sorkin's causets: http://www.physics.syr.edu/~sorkin/causet.program [Broken]
    Last edited by a moderator: May 1, 2017
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