Question about cgs vs SI units in the context of the Debye Length

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Would have thought cgs and SI would give the same debye length when converted to the same units, but they don't. What is the physical meaning difference, and how do I know which equation to use.
Hello - I am trying to understand the physical meaning the undergirds the Debye length as it pertains to different unit systems. I understand that fundamentally its the distance at which the distribution of ions doesn't differ by more than the effect of k_B*T from the rest of the solution, plasma, whatever. But what I don't understand is why cgs and SI can give such radically different values. If they just came out as different values with different units, whatever. But I can convert both to meters, and get completely different numbers. I'm writing a review article, and this isn't really my field, but all the papers I came across had different expressions, and I dug a little deeper, and found this confusion, and I don't know how to resolve it. I'd just be somewhat vague, but I don't even know how to kindof defend the choice of one or the other equation, other than saying, "everywhere else I used SI," which isn't a very good answer.

HELP!
 
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ehchandlerjr said:
TL;DR Summary: Would have thought cgs and SI would give the same debye length when converted to the same units, but they don't. What is the physical meaning difference, and how do I know which equation to use.

Hello - I am trying to understand the physical meaning the undergirds the Debye length as it pertains to different unit systems. I understand that fundamentally its the distance at which the distribution of ions doesn't differ by more than the effect of k_B*T from the rest of the solution, plasma, whatever. But what I don't understand is why cgs and SI can give such radically different values. If they just came out as different values with different units, whatever. But I can convert both to meters, and get completely different numbers. I'm writing a review article, and this isn't really my field, but all the papers I came across had different expressions, and I dug a little deeper, and found this confusion, and I don't know how to resolve it. I'd just be somewhat vague, but I don't even know how to kindof defend the choice of one or the other equation, other than saying, "everywhere else I used SI," which isn't a very good answer.

HELP!
Maybe, the following might be of help (from the University of Maryland):

Converting between SI and Gaussian units

 
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SI and cgs units can have different values even for observables with no units. For example the magnetical susceptibility ##\chi## is given in SI by ##\mathbf M = \chi \mathbf M## but in the usual cgs (Gaussian) units it is given by ##\mathbf M = 4\pi \chi \mathbf H##. So in SI, superconductors have ##\chi=-1## and in cgs ##\chi=-\frac{1}{4\pi}##.

THAT SAID: I think that the Debye length should be the same in cgs and SI. What values are you using can you provide an example?
 

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