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RogerPink
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Never Mind.
reilly said:Perhaps you might explain the specifics of my lack of understanding. Thank you. Reilly Atkinson
Great, so why did you not simply ask about gravitational modifications of the uncertainty principle ? You have to be careful what you mean here since [x,p] = i \hbar is valid by definition. In Newtonian gravity coupled to the Schrodinger equation, you are not going to get anything new (what is done in these papers is a classical analysis of error propagation) : the momentum here is still the free Euclidean momentum m dx/dt, moreover in order to import the Planck scale, you need G,c and \hbar, that is at least a relativistic quantum theory coupled to a gravitational background. In that case, choose a particular coordinate system as well as some state, and you will see that the kinetic term (mass) receives gravitational corrections. Hence, the correct momentum deviates from ``free'' momentum - just as this occurs in gauge theories. So, it is obvious that corrections arise on the uncertainty relations for the ``free'' momentum mdx/dt which you can guess by dimensional analysis.RogerPink said:Here is a great paper that has answered some of my questions.
Generalized Uncertainty Relations Phys Rev. A vol 35 pg 1486
And just so I'm clear here, I'm no longer asking a question of the forum, I'm just posting things I found helpful in my search for a clearer understanding of the limits of the uncertainty relation. If this is not an appropriate use of the forum, I won't be offended if this thread is killed.
RogerPink said:The uncertainty equation is equal to h-bar over 2 and as I understand it, the 2 comes from the minimum standard deviation for a gaussian distribution. Which is to say the relation would be different if the error for position and momentum were represented by a different kind of distribution. Was there a physical reason for this choice of distribution or did this type of distribution just fit the data. Considering the precision to which Quantum Mechanics has been tested, the gaussian distribution is obviously correct, I'm just wondering if there was a physical reason he chose it.