Is the Ohm's law verified to hold true at all temperatures? If not, then till what temperature does the Ohm's law hold?

I think it is valid only till $0$ K and above. Am I right in my thinking?

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    $\begingroup$ Ohm's law is valid for Ohmic devices. $\endgroup$ – Yashas May 13 '17 at 2:39
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    $\begingroup$ I think you can look for when the material has convection and diffusion. I think Ohm's law stops being valid when velocity dependent terms or terms involving the gradient of the number density becomes comparable to the terms proportional to the electric field. Ohmic devices have convection and diffusion that doesnt depend on electromagnetic fields. (I read something like that in Alan J. Grodzinsky. Fields, Forces, and Flows in Biological Systems. Garland Science, 2011.) $\endgroup$ – Emil May 13 '17 at 6:39
  • $\begingroup$ ... I read something like that on page 42. The equation looks pretty much like Lorentz force law plus convection plus diffusion. $\endgroup$ – Emil May 13 '17 at 6:46
  • $\begingroup$ (Or rather Lorentz force law * mobility plus diffusion plus convection. I think the Lorentz-y term was called migration flux.) $\endgroup$ – Emil May 13 '17 at 6:54
  • $\begingroup$ @Emil I am afraid that I do not have access to the book that you have quoted from but to me convection implies a temperature difference and diffusion a concentration gradient? With the Lorentz force present there must be a magnetic field. $\endgroup$ – Farcher May 13 '17 at 10:05

Ohm's law is a statement regarding the relationship between potential difference and current - they are proportional to one another.
What one can do is to decide whether or not for a particular object that relationship between potential difference and current is followed.
Whether or not an object follows Ohm's law makes no difference to the statement which we call Ohm's law.

So there can be no verification of Ohm's law rather one can test whether or not an object obeys Ohm's law.

  • $\begingroup$ You are right, but it is clear that this question is not about terminology, instead the op would like to know when usual objects obeys Ohm's law. $\endgroup$ – Spirine May 13 '17 at 7:34
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    $\begingroup$ @Spirine I understand your comment but only the OP can rephrase the question. My answer is that Ohm's law is true for all temperatures. $\endgroup$ – Farcher May 13 '17 at 10:05
  • $\begingroup$ The question is exactly about terminology. The OP thinks Ohm's Law is like Newton's Laws or the 2nd Law of Thermodynamics - some fundamental law of naure. In fact, as you state, it's a handy observation that holds for certain useful devices in the range of conditions we use them. We should call it Ohm's Rough Rule of Thumb for Resistors. $\endgroup$ – Oscar Bravo Jul 27 at 8:40
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    $\begingroup$ @OscarBravo how about George's guess... $\endgroup$ – user207455 Jul 27 at 8:45

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