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I think quantum state collapse is in contradiction with the storage of QBits

  1. Jun 6, 2006 #1
    This is my analysis:1)quantum can have two states at one time:0 and 1.So n QBits have the volume 2^n. 2)when it's observed,the quantum state will collapse to a certain one.

    So the comtradiction is evidence:the information of the 2^n Qbits disappear when I only read n Qbits from it.

    Ok...if it is wrong,why?
  2. jcsd
  3. Jun 7, 2006 #2
    Is my description not clear or the question itself hard to answer? ^_^
  4. Jun 7, 2006 #3
    Your description is quite poorly worded, I'm afraid no one understands what the question is. I suspect you might be confusing the number of qbits, which is n, with the number of possible outcomes of measurement on the n qubits, which is 2^n. It's combinatorics - if you have 1 qbit, measurement will yield one of 2^1 = 2 possiblities, namely 0 or 1.

    Your language is not standard and contributes to the communication barrier here. "Volume" means nothing to me in this context. "...can have two states at once" is not allowable in quantum mechanics, in the usual definition of the words; e.g. a superposition state is itself a unique state.
  5. Jun 7, 2006 #4
    Thanks for your comment and explanation of QM.

    So what you implied is the information in superposition state is absolutely unknowable.When we measure it,it just appear 0 or 1 by chance?
    And this "possiblities-attribute" of QM make no contribution to the memorizer?
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