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I wonder if I'm the only one who thoroughly enjoyed Dana's post.

On 2/1/08, Dana Dorsett <[log in to unmask]> wrote:
>
>
>
> Rachel Rose [[log in to unmask]] writes:
>
> >last itme i checked the laws of physics there was something about not being
> able to be in two places at once.
>
> >Maybe that also explain why you haven't seen me. i'm where i am and you're
> where you are...not one and the
>
> >same place.
>
> Or maybe you're rilly rilly tiny and movin' rilly rilly FAST!?!
>
> Last time I checked the laws of physics:
>
> Locating a particle in a small region makes the momentum of the particle
> uncertain, and conversely, measuring the momentum of a particle precisely
> makes the position uncertain.
>
> In quantum mechanics, the position and momentum do not have precise values,
> but have a probability distribution. There are no states in which a particle
> has both a definite position and momentum. The narrower the probability
> distribution is in position, the wider it is in momentum.
>
> A mathematical statement of the principle is that every quantum state has
> the property that the root-mean-square (RMS) deviation of the position from
> its mean (the standard deviation of the X-distribution):
>
>
>
>
> times the RMS deviation of the momentum from its mean (the standard
> deviation of P):
>
>
>
>
> can never be smaller than a small fixed multiple of Planck's constant:
>
>
>
>
> The mathematical statement implies the physical statement. Once an observer
> measures the position of a particle with accuracy ΔX, the state of the
> particle immediately after the measurement has .
>
> The uncertainty principle is related to the observer effect, with which it
> is often conflated. In the Copenhagen interpretation of quantum mechanics,
> the uncertainty principle is a theoretical limitation of how small the
> observer effect can be. A precise position measurement must alter the
> momentum by a large indeterminate amount and vice-versa.
>
> While this is true in all interpretations, in many modern interpretations of
> quantum mechanics (many-worlds and variants), the quantum state itself is
> the fundamental physical quantity, not the position or momentum. Taking this
> perspective, while the momentum and position are still uncertain, the
> uncertainty is not just an effect caused by observation, but by any
> entanglement with the environment.
>
> So, where the lleh are you (and how fast are you goin')?
>
> (Sure wish it were snowing hard instead of R**Nin' hard! :-(  )
>
> dana
>
> _____________ ________ __
>
> __ /________ ________ ___
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> __( ________ __山スキー!_
>
> ___¥ ________ ________ __
>
> ____) ______ __________ _
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> ___/ ______ ___________ _
>
> __(  o ____ __________ __
>
> __ ¥(|¥.____ _______ ____
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> ___`¥>/______ ____ ______
>
> ____ ¥` ______ __ _______
>
> ______`________ _ _______
>
> _______________ __ ______
>
>
>
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