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Magnetic dipole interactionby darkdave
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#1
Feb813, 01:03 PM

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I am simulating protons and electrons in a simulator that runs 1 femto seconds per second up to 1 second per second. So it can accurately show the passage of charge particles through space with data being updated on their displacement, velocity and acceleration.
However I am now adding in rotational data. This means that I need to simulate angular momentum and torque. How do I do this? For the electron do I have to calculate the torque at the classical electron radius at each pole due to magnetic interaction with other charged particle poles? 


#2
Feb813, 05:26 PM

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In a classical simulation, particles cannot rotate. If you want "rotating" particles, you need quantum mechanics  and if spin is relevant, I would expect that everything else should use quantum mechanics as well.



#3
Feb813, 11:56 PM

P: 21

I am aware of the quantum complication but at the same time i can still create a bhor model intepretation since i know the angular momentum of the particle and its mass and classical radius. I just need to know how to simulate the particles changing orientation due to torque caused by external magnetic fields. Wether i choose to show particles spinning or not is irrelevant to what im asking since all i should be concerned about is the angular momentum of the particle.



#4
Feb913, 04:32 AM

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P: 11,631

Magnetic dipole interaction
The Bohr model works reasonably well for hydrogenlike atoms without spin, and nothing else, as far as I know.



#5
Feb913, 04:38 AM

P: 21

What is the vector B representing in that formula?



#6
Feb913, 04:42 AM

P: 21

ok i looked up that formula Force = charge velocity cross product magnetic field. The vector representing Magnetic field does it point to the center of the particle that acts like a magnet? For example is B pointing to the center of an electron if we are modeling 2 electrons that are interacting not just electrically but magnetically as well due to each of them having a magnetic field due to their intrinsic angular momentum



#7
Feb913, 04:43 AM

P: 21

Also what if the velocity of the particle is ZERO? Isnt the current orientation more relevant here?



#8
Feb913, 04:46 AM

P: 21

so think about it this way, we have 2 electrons each with a north and south magnetic pole and i want to simulate each electron turning its North Poles toward the other electron's South Pole. And each like poles repelling each other. So basicly i need to know torque.



#9
Feb913, 05:26 AM

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Don't forget the electric part, it will be retarded as well. 


#10
Feb913, 05:29 AM

P: 21

What about this article? Sounds to me electrons have a magnetic field of their own.
http://en.wikipedia.org/wiki/Electro..._dipole_moment Also are you saying that an electron HAS NO ORIENTATION? 


#11
Feb913, 05:36 AM

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Electrons are pointlike. What is the orientation of a point? 


#12
Feb913, 06:18 AM

P: 21

What I want to do is simulate electrons behaviour much like how real magnets behave when they are in close proximity. Their poles should point toward or away from other particle's dipoles. 


#13
Feb913, 06:50 AM

P: 21

The electron is a charged particle of charge (−e), where e is the elementary charge. Its angular momentum comes from two types of rotation: spin and orbital motion. From classical electrodynamics, a rotating electrically charged body creates a magnetic dipole with magnetic poles of equal magnitude but opposite polarity. This analogy holds as an electron indeed behaves like a tiny bar magnet. One consequence is that an external magnetic field exerts a torque on the electron magnetic moment depending on its orientation with respect to the field. 


#14
Feb913, 11:18 AM

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A magnetic dipole is not something with a north and a southpole. The dipole has an orientation, but that can be a superposition of multiple possible orientations, and the strength of the dipole, measured in an arbitrary direction, is always a fixed number (for electrons) and just the sign is variable. There is no way to model this classically.



#15
Feb913, 12:20 PM

P: 21

so what do you suggest is the best way to simulate electrons in as much classical way as possible?
I mean I know they dont have "spin": in the classic sense, but I can still make them spin based on known facts for example: the classical radius of the electron, the known mass and the known angular momentum. This way they behave in a way that is not true to reality but its still based on real data so intuitively it has some hidden truth. What could I do for magnetic fields of the electron to do something similar to what i just proposed? 


#16
Feb913, 01:59 PM

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#17
Feb913, 02:10 PM

P: 21

can you propose a setup?
So far I know I want to show the electron spinning based on the available data of known intrinsic angular momentum, mass and classical electron radius. Can you use that as a setup? And fill in any blanks for me at your discretion. I basicly want to show the particle changing orientation in real time in reaction to a neighboring particle's magnetic influence. If it cannot be continuus then make compromises. I can make the particle perform discrete changes in orientation if need be. BUT I NEED A MODEL ANYKIND OF MODEL ASAP!! :) 


#18
Feb913, 03:00 PM

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I doubt that the results will be good, but maybe you can add dipoledipole interactions with the electron magnetic moment in a classical way. But if it does not influence anything, where is the point? 


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