I ask my new best friend Deepseek: "does electric current exist?" It replies-
Does Electric Current Exist? A Deep Dive into the Debate
The question of whether electric current "exists" might seem absurd at first—after all, we use electricity every day! However, the nature of electric current has been debated among physicists and engineers, particularly by iconoclasts like Ivor Catt, who challenged classical electromagnetic theory.
1. The Conventional View: Yes, Current Exists
In standard electromagnetism (Maxwell’s equations, Ohm’s Law), electric current (I) is defined as:
The flow of electric charge (electrons/holes) per unit time (I=dQ/dt).
Measured in Amperes (A), observed in circuits via:
Magnetic fields (Oersted’s experiment).
Heating (Joule effect, P=I^2R
Electrolysis (Faraday’s laws).
Evidence for Current:
✅ Wires heat up when current flows (Joule heating).
✅ Compass needles deflect near current-carrying wires (Ampère’s law).
✅ Batteries discharge in a closed circuit.
2. The Dissenting View: Ivor Catt’s Argument
Ivor Catt (1935–2023) controversially claimed:
"Electric current is an illusion. Energy flows in the dielectric (insulator/space around wires), not the conductor."
His key points:
Wires guide energy, but don’t carry it.
Energy propagates as TEM (Transverse Electromagnetic) waves in the dielectric (e.g., air, insulation).
The "current" in wires is just a side effect of boundary conditions.
Displacement current is a "fraud" (rejects Maxwell’s version).
Electrons move too slowly (~mm/s drift velocity) to explain instantaneous energy transfer.
Example:
When you flip a light switch, the bulb lights up at nearly the speed of light, not due to electron flow but because EM waves travel in the field around the wire.
3. Quantum & Relativistic Perspectives
Modern physics complicates the picture:
Quantum mechanics: Electrons behave as both particles and waves; "current" is a statistical flow of charge carriers.
Special relativity: In a wire, the electric field (not just moving electrons) determines energy transfer.
4. Practical Reality for Engineers
While Catt’s ideas are provocative, engineers treat current as real because:
Circuit theory works (Ohm’s Law, Kirchhoff’s Laws).
Instruments measure current (ammeters, Hall effect sensors).
Semiconductors rely on charge flow (diodes, transistors).
However, Catt’s critique reminds us:
⚠️ Energy is stored in fields, not just moving electrons.
⚠️ High-speed signals behave as waves, not just "current."
Conclusion: Does Current Exist?
Yes, in the classical, measurable sense (charge flow, magnetic effects).
No, if you adopt Catt’s field-centric view (energy flows outside wires).
It’s a model: Like "voltage" or "force," current is a useful abstraction—but deeper
physics (EM fields, QM) underlies it.
For daily electronics, current is "real." For theoretical EM, it’s part of
a larger energy-transfer mechanism.
Want to explore further? Ask about:
Catt’s "Heaviside Signal" vs. Maxwell’s waves.
How PCBs actually transfer energy (hint: it’s not just electrons!).
You can design high speed circuits with more confidence that it will work as expected. I think many optimisations and improvements are possibile, and nobody has even scratched the surface of what can be done.
I ask my new best friend Deepseek: "does electric current exist?" It replies-
Does Electric Current Exist? A Deep Dive into the Debate
The question of whether electric current "exists" might seem absurd at first—after all, we use electricity every day! However, the nature of electric current has been debated among physicists and engineers, particularly by iconoclasts like Ivor Catt, who challenged classical electromagnetic theory.
1. The Conventional View: Yes, Current Exists
In standard electromagnetism (Maxwell’s equations, Ohm’s Law), electric current (I) is defined as:
The flow of electric charge (electrons/holes) per unit time (I=dQ/dt).
Measured in Amperes (A), observed in circuits via:
Magnetic fields (Oersted’s experiment).
Heating (Joule effect, P=I^2R
Electrolysis (Faraday’s laws).
Evidence for Current:
✅ Wires heat up when current flows (Joule heating).
✅ Compass needles deflect near current-carrying wires (Ampère’s law).
✅ Batteries discharge in a closed circuit.
2. The Dissenting View: Ivor Catt’s Argument
Ivor Catt (1935–2023) controversially claimed:
"Electric current is an illusion. Energy flows in the dielectric (insulator/space around wires), not the conductor."
His key points:
Wires guide energy, but don’t carry it.
Energy propagates as TEM (Transverse Electromagnetic) waves in the dielectric (e.g., air, insulation).
The "current" in wires is just a side effect of boundary conditions.
Displacement current is a "fraud" (rejects Maxwell’s version).
Electrons move too slowly (~mm/s drift velocity) to explain instantaneous energy transfer.
Example:
When you flip a light switch, the bulb lights up at nearly the speed of light, not due to electron flow but because EM waves travel in the field around the wire.
3. Quantum & Relativistic Perspectives
Modern physics complicates the picture:
Quantum mechanics: Electrons behave as both particles and waves; "current" is a statistical flow of charge carriers.
Special relativity: In a wire, the electric field (not just moving electrons) determines energy transfer.
4. Practical Reality for Engineers
While Catt’s ideas are provocative, engineers treat current as real because:
Circuit theory works (Ohm’s Law, Kirchhoff’s Laws).
Instruments measure current (ammeters, Hall effect sensors).
Semiconductors rely on charge flow (diodes, transistors).
However, Catt’s critique reminds us:
⚠️ Energy is stored in fields, not just moving electrons.
⚠️ High-speed signals behave as waves, not just "current."
Conclusion: Does Current Exist?
Yes, in the classical, measurable sense (charge flow, magnetic effects).
No, if you adopt Catt’s field-centric view (energy flows outside wires).
It’s a model: Like "voltage" or "force," current is a useful abstraction—but deeper
physics (EM fields, QM) underlies it.
For daily electronics, current is "real." For theoretical EM, it’s part of
a larger energy-transfer mechanism.
Want to explore further? Ask about:
Catt’s "Heaviside Signal" vs. Maxwell’s waves.
How PCBs actually transfer energy (hint: it’s not just electrons!).
Forest, I'm an engineer. What does this different model let me do, or do easier, that the old model doesn't?
I'll answer your question in another post.
You can design high speed circuits with more confidence that it will work as expected. I think many optimisations and improvements are possibile, and nobody has even scratched the surface of what can be done.