Tesla worked with DC direct current then AC alternating current which was a continuous current that fluctuated in polarity and his final and most favorite invention was short pulsed current with extremely short pulses which is different than alternating current this hairpin circuit produces that and
(waveguide.blog)https://waveguide.blog/brief-history-tesla-hairpin-circuit-stout-copper-bars/Tesla worked with DC direct current then AC alternating current which was a continuous current that fluctuated in polarity and his final and most favorite invention was short pulsed current with extremely short pulses which is different than alternating current this hairpin circuit produces that and allows a lot of different interesting phenomenon such as being able to deliver power with one wire instead of having a return path for the power. Additionally others and maybe Tesla himself have speculated that there is almost no resistance in wires when extremely short voltage pulses are sent down the wire because the electrons don't have time to be moved by the electrostatic charge that it is the voltage. So you have voltage without the traditional idea of electrons carrying the current. Yet you still have current which shows that it is not actually the electrons that carry the current but actually that electrons are moved along by the electrostatic charge and the current is a separate function.
This means very thin wires can carry this cold electricity as he sometimes called it or very short duration pulse electricity. Once again this electricity differs from alternating current because alternating current ramps up relatively slowly 160th of a 2nd typically in America to its peak and then down again to its opposite polarity in a smooth sine wave. The electricity that Tesla discovered here instead goes from 0 to maximum voltage in almost an instant and is instantly quenched and disappears and then rapidly does it again. So it's frequency is high but it is not a continuous AC current and it is of extremely rapid rise and short duration. It's like the difference between pushing on a nail from two sides of a board repetitively over and over and that's AC current versus hitting a nail with a hammer blow in many rapid successions from one side of the board. The blows are instantaneous and very short even though many of them can happen very quickly.
That is cold electricity and that is why some people and don't do this some people have shown that you can hold a wire underwater while it's lighting a bulb when the electricity is produced this way and you can send a lot of power down one very thin wire that would normally require too much thicker wires if it was normal AC current or DC current. And you can do a lot of other interesting things with it.
Now I will say I don't think the author of this article quite understands what this is. He says it's not a special form of electricity that it's simply high frequency electricity but what he doesn't seem to understand is that it is a very very short pulse durations and so it is a different form of electricity than AC current. it is not common.
