- #1
dsoodak
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One of the first things about QM we were taught in my undergraduate physics program is the deBroglie relation:
λ = h/p
Now, it makes sense that that this might hold for all elementary particles, especially since the evidence generally seems to suggest that the commonly observed forms of matter and energy are basically made of the same stuff.
However, it doesn't logically follow that the same holds true for things like atoms and molecules (or even protons). This would suggest that all the constituents somehow "know" that they are part of a larger system and adjust (and sync up) their wavelengths accordingly.
The way I would expect this to be approached is to treat an atom (or maybe just start with something simpler like an electron-positron pair) as a multi-particle system, then calculate where all the individual particles would end up when shoved through a 2-slit experiment. Then the professor would say: "Notice that when you express this in terms of the center of mass of the system, you get the same equation as you would for a single particle whose mass is the sum of the parts". If you skip this step, you have an over-defined mathematical equation.
So...can anyone point me to this derivation? I assume that I was not given it because it is too complicated to teach undergraduates. We already know its true from experimental evidence, but it seems like SOMEONE would have double checked the math...
Dustin Soodak
λ = h/p
Now, it makes sense that that this might hold for all elementary particles, especially since the evidence generally seems to suggest that the commonly observed forms of matter and energy are basically made of the same stuff.
However, it doesn't logically follow that the same holds true for things like atoms and molecules (or even protons). This would suggest that all the constituents somehow "know" that they are part of a larger system and adjust (and sync up) their wavelengths accordingly.
The way I would expect this to be approached is to treat an atom (or maybe just start with something simpler like an electron-positron pair) as a multi-particle system, then calculate where all the individual particles would end up when shoved through a 2-slit experiment. Then the professor would say: "Notice that when you express this in terms of the center of mass of the system, you get the same equation as you would for a single particle whose mass is the sum of the parts". If you skip this step, you have an over-defined mathematical equation.
So...can anyone point me to this derivation? I assume that I was not given it because it is too complicated to teach undergraduates. We already know its true from experimental evidence, but it seems like SOMEONE would have double checked the math...
Dustin Soodak