"Heat current" on a microscopic level

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Electric current involves the transport of electric charge, specifically the flow of electrons, which generates magnetic fields and can charge capacitor plates. In contrast, heat current refers to the transport of kinetic energy without the movement of particles, focusing solely on energy flow. The mathematical descriptions of electric and heat currents show similarities, with electric current density related to electric potential and heat current density linked to temperature gradients. The discussion highlights the need for clarity in formulating questions to facilitate deeper understanding. Overall, the distinction lies in the nature of what is being transported: charge for electric current and energy for heat current.
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What is the difference on microscopic level between electric current and heat current(conduction)?
 
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Electric current describes a transport of electric charge and the heat current a transport of heat energy.
 
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It may be of interest that with electric current, there is a flow of charged particles, (electrons in the direction opposite the current flow), and the result is magnetic fields are produced (Biot-Savart), and capacitor plates can become charged.
With heat current, there is no overall transport of particles. It is simply a flow of the kinetic energy.
 
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vanhees71 said:
Electric current describes a transport of electric charge and the heat current a transport of heat energy.
Please understand my question more deeply
 
Then you have to more clearly express your question :-).
 
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Charles Link said:
It may be of interest that with electric current, there is a flow of charged particles, (electrons in the direction opposite the current flow), and the result is magnetic fields are produced (Biot-Savart), and capacitor plates can become charged.
With heat current, there is no overall transport of particles. It is simply a flow of the kinetic energy.
I am not talking about those trivial stuff
 
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vanhees71 said:
Then you have to more clearly express your question :-).
It doesn't matter. Sorry for bothering you.
 
zb23 said:
I am not talking about those trivial stuff
It seems like a good question you asked. Without the details of the "trivial stuff", there perhaps isn't much difference between electric current flow and energy flow.
e.g. if the charge balances in the conductor carrying current, how do you know that there is a flow of charge as opposed to a flow of energy/heat ?
 
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Mathematically the description of each isn't too different. For electric current one case you could consider is where Ohm's law holds i.e. the electric current density can be shown to satisfy$$\mathbf{j}_e = -\sigma \nabla \phi$$For heat current, if you assume that there is no convection component (i.e. if we assume there is only a Fick's law diffusion component) to the heat current density, you can describe it as$$\mathbf{j}_h = -D\nabla T$$In this way there is a correspondence between ##\phi \leftrightarrow T## and ##\sigma \leftrightarrow D##
 
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Caloric does not carry charge?o_O
 
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zb23 said:
Please understand my question more deeply
Please put more effort into your question. The answer you got was the answer to the question you asked. We cannot read your mind, so we don’t know what deep question you are asking unless you put in the effort to formulate it clearly and write it down. All we can do is respond to what you write. We are physicists, not psychics.
 
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