Is Electric Potential value classical?

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kiki_danc
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There is no absolute electric potential.

Is it due to classical ignorance (because we don't know the static fields, capacitive coupling, etc. of the surrounding environment) or is it due to quantum ignorance (the potential can fluctuate to any value due to HUP)? My question is valid because electric potential is part of quantum electrodynamics. So it has quantum label.
 
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The electric potential is classical. It does appear in quantum mechanical problems (not just QFT, it shows up when solving Schrödinger's equations for bound electrons in an atom) but that doesn't make it a quantum phenomenon. We're just using quantum mechanical methods to calculate how particles respond to the electric potential; if we were working a problem in which quantum effects didn't matter we'd use classical methods to calculate how particles respond to the electric potential.

The potential has no absolute value, but this nothing whatsoever do with the HUP, quantum uncertainty, quantum fluctuations, or the like. It has no absolute value because it is defined as the absolute difference from an arbitrarily chosen reference value. It's like altitude (you get one value if you want height above sea level, another if you want height relative to the Earth's surface nearby, yet another if you want distance from the center of the earth) or velocity (you get one value if you want velocity relative to the surface of the earth, another if you want velocity relative to the sun, another if you want velocity relative to automobile you happen to be driving, ...).
 
Nugatory said:
The electric potential is classical. It does appear in quantum mechanical problems (not just QFT, it shows up when solving Schrödinger's equations for bound electrons in an atom) but that doesn't make it a quantum phenomenon. We're just using quantum mechanical methods to calculate how particles respond to the electric potential; if we were working a problem in which quantum effects didn't matter we'd use classical methods to calculate how particles respond to the electric potential.

The potential has no absolute value, but this nothing whatsoever do with the HUP, quantum uncertainty, quantum fluctuations, or the like. It has no absolute value because it is defined as the absolute difference from an arbitrarily chosen reference value. It's like altitude (you get one value if you want height above sea level, another if you want height relative to the Earth's surface nearby, yet another if you want distance from the center of the earth) or velocity (you get one value if you want velocity relative to the surface of the earth, another if you want velocity relative to the sun, another if you want velocity relative to automobile you happen to be driving, ...).

I read in Wiki that "In particle, physics, the electoweak scale, also known as the Fermi scale, is the energy scale around 246 Gev, a typical energy of processes described by the electroweak theory.". can 246 GeV be part of the electric potential?

It is said we can't measure the absolute value of the potential. But if you will put your AC generator in an ambient 246 GeV field. It is in plasma and the generator can melt so you can tell the absolute value of the potential which is not in our Earth potential.

Where does my confusion lies? Thanks.
 
kiki_danc said:
It is said we can't measure the absolute value of the potential.

You can't measure something that doesn't exist by definition.

kiki_danc said:
Where does my confusion lies?

You don't understand the basic definition of electric potential: the amount of work needed to move a unit of positive charge from a reference point to a specific point inside the field without producing an acceleration.

Since it depends on two points, which can vary in location, there cannot be a single value for the electric potential at a single point. With only a single point you're missing half the definition!