How to observe the future?


by Count Iblis
Tags: future, observe
Count Iblis
Count Iblis is offline
#1
Nov20-07, 10:31 AM
P: 2,159
If A is the observable corresponding to observing the lottery draw, how can I measure the operator

[tex]A\left(t\right)=\exp\left(i H t/\hbar\right)A\exp\left(-i H t/\hbar\right)[/tex]



And how to make sure that I can act on the observation of next week lottery draw by submitting the correct numbers without perturbing the wavefunction of the universe so much that it won't evolve to the desired state?
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olgranpappy
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#2
Nov20-07, 10:10 PM
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In order that we may begin to answer your question, could you give us the explicit form of the Hamiltonian?

...oh, actually... I need the state of the system too...

...and, darn it, even then I'll only be able to give you the expected value which results from repeated measurement... shame.
vanesch
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#3
Nov21-07, 01:24 AM
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You face the same problem in a Newtonian universe...

Count Iblis
Count Iblis is offline
#4
Nov21-07, 08:23 AM
P: 2,159

How to observe the future?


Quote Quote by olgranpappy View Post
In order that we may begin to answer your question, could you give us the explicit form of the Hamiltonian?

...oh, actually... I need the state of the system too...

...and, darn it, even then I'll only be able to give you the expected value which results from repeated measurement... shame.
I agree, except with the last statement. If you could measure A(t), the wavefuncion will collapse into some eigenstate of A(t) which is a state that will go on to evolve to an eigenstate of A a time t later corresponding to the same eigenvalue that you measured.
maqsood
maqsood is offline
#5
Nov22-07, 04:27 AM
P: 1
i am a fresh student of telecom engineering. would any one tell me the useful site in which i could find the basic concepts and understanding and reasoning phenomenan rather than only mathematical derivations. thanx.


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