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bio website marty-green.blogspot.com
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Jan
19
comment Some applications of the Einstein-Podolsky-Rosen (EPR) paradox?
You should know that I suffer from a low-level personality disorder which compels me to disagree with authority figures. Recently a Provincial Court judge has upheld the University of Winnipeg's decision to bar me from the campus because of my "single-minded determinedness to demonstrate that (my) point of view is the superior one". You can read the full decision here (quoted passage from paragraphs 46-50): canlii.org/en/mb/mbpc/doc/2014/2014mbpc42/2014mbpc42.html
Jan
18
comment Some applications of the Einstein-Podolsky-Rosen (EPR) paradox?
But your professional physicists DID get it wrong. They show the particles shotting out of the block along opposite trajectories, towards distant detectors. You already pointed out that they should have had submicroscopic detectors in the interstitial spaces between the uranium atoms (!). That's not what they're showing in their picture.
Jan
16
comment Some applications of the Einstein-Podolsky-Rosen (EPR) paradox?
And yes, I think physicists are extremely sloppy in this kind of thing. Like the authors of that paper you referred me to who used exactly my setup of an example of producing entangled pairs. It only works for isolated atoms, not a block. They forgot to take into account the momentum absorbed by the uranium sample.
Jan
16
comment Some applications of the Einstein-Podolsky-Rosen (EPR) paradox?
I appreciate your interest in my opinion, but I don't think I could have been more clear in my last statement: you should be suspicious of highly contrived measurement proposals. Surely you've read Feynmann's story of how people proposed different methods of measuring which slit the electron went through (he was drawing on the extended correspondence between Bohr and Einstein on this question) only to show that all such efforts were ultimately frustrated by the uncertainty principle.
Jan
16
answered How was it proven that a quantum entanglement measurement of particle A, affects properties of particle B
Jan
14
comment Physical meaning of linear combination of possible states in infinite well
And don't forget that all the states you mix together have a time component...they are multiplied by exp(jwt), where w depends on the energy level. So the pattern is changing with time as the relative phases move with respect to one another.
Jan
14
comment Physical meaning of linear combination of possible states in infinite well
The amplitudes don't remain fixed in time. You need to think about the simple example I gave where you mix just the the ground function and the first excited state. Since the electron is bouncing back and forth, it is radiating. So it loses energy. The amplitude "drains" from the excited state to the ground state until eventually it stops moving. It's the exact same thing that happens to a hydrogen atom in a superposition of the ground (1s) state and first excited (2p) state.
Jan
13
comment Physical meaning of linear combination of possible states in infinite well
You're assuming you add them all in phase at the middle of the box and with equal amplitudes. Yes, you get a wave packet at that instant but I don't think it holds together...I think it explosed all over the box. I'm not sure it's all that easy to get coherent packets that stick together, like the ones you can create in the harmonic oscillator potential.
Jan
13
answered Physical meaning of linear combination of possible states in infinite well
Jan
11
comment Some applications of the Einstein-Podolsky-Rosen (EPR) paradox?
In general, it's a good idea to be suspicious if you find yourself going to extreme lengths to justify how something might be measurable.
Jan
11
comment Some applications of the Einstein-Podolsky-Rosen (EPR) paradox?
@hypnosifl I'm not sure that the very problematical measurement system you propose actually meets the condition of being executable even "in principle". But if it is, you're saying that if you had a properly isolated block of uranium emitting a continuous flux of alpha particles...that you wouldn't be able to set up a double-slit system and measure a diffraction pattern? I don't think that's right. I think you would get a diffraction pattern.
Jan
11
comment Some applications of the Einstein-Podolsky-Rosen (EPR) paradox?
If you have only one uranium atom, then when it decays, the momentum of the thorium must be equal and opposite to the momentum of the alpha particle. If there's a block or uranium, no such restriction. The momentum is divided three ways, so measuring the alph particle tells you nothing about the momentum of the thorium atom.
Jan
11
comment Some applications of the Einstein-Podolsky-Rosen (EPR) paradox?
@hypnosifl your answer is very helpful and I am still trying to work out the consequences; but I see now that the example I gave fails to create faste-than-light communication for a more prosaic reason. You DO get an interference pattern because when I substitued the block of uranium for the single uranium atom, I lost the perfect entanglement of the momenta of the thorium and alpha particles. The momenta were only entangled because there was nowhere else to go when the SINGLE uranium atom decayed. There is no entanglement with a block of uranium.
Jan
10
revised Some applications of the Einstein-Podolsky-Rosen (EPR) paradox?
added 2246 characters in body
Jan
10
comment Some applications of the Einstein-Podolsky-Rosen (EPR) paradox?
I can't comment on your question as to how the thorium atom is linked to the alpha particle. In standard QM, we say they do not each have their own independent wave function, but instead there is a single six-dimensional wave function which contains both of them. (That's the wave function that "collapses" when either one is detected.)
Jan
9
answered Some applications of the Einstein-Podolsky-Rosen (EPR) paradox?
Jan
6
answered Plants and Quantum Mechanics!
Dec
29
comment Why are electromagnetic waves not able to pass through a hole with a diameter smaller than the wavelength?
Oh come on. If you merge the two holes into one, the diameter becomes squrt(2). And the power is 4 times: that is, diameter to the fourth. Like I said in the first place. For a correct explanation of the exponent, re-read what I wrote in my answer.
Dec
27
answered Why are electromagnetic waves not able to pass through a hole with a diameter smaller than the wavelength?
Dec
23
answered On the foundations of quantum physics