V = I R
As I tap away on the tablet computer which I use to write this, the sounds of Dvorak's 9th Symphony "The New World Symphony" plays through my earphones. I have heard this so many times that I virtually know where every single note is, what's been before and what's coming up. The computers inside the tablet, the earphones themselves, the train which I am in, and even the impulses which pass from my ears to my brain are all driven by electricity and all of them are governed by the insanely simple equation which describes all the electricity in the universe: V = I R.
Voltage, that is the potential difference in energy between two points within an electric circuit, equals the amount of current which flows multiplied by the amount of electrical resistance in the system. This is the story of the computer age, the electronic age and contained within the bodies of every single living thing that ever was, the story of life itself. When no more current passes through the body of a living thing, it is dead. That even includes the micro, pico, atto and femto currents in the cells of trees, plants and algae but also of single cell bacteria and viruses.
The entire of chemistry, is really just the interaction of particles but mostly the passage of electrons writ large; expanded to many layers of extraction. When you talk about chemical bonds or chemical reactions, really you're talking about the interaction of atoms and their electrons. It isn't a very long journey to go from chemical reactions to the flow of electrons through wires and into the world where they encounter resistance and dump their potential energy somewhere: V = I R
When you have the movement of just a single electron, for the very small amount of time that it has moved from one place to another, that is a calculable flow of current. Any resistance that that electron encounters can also in theory be calculated. The difference between the two energy states before and after it has moved, represents the change in potential difference, which is the voltage.
I don't know about you but I find that to be most singular.
In the case of a rock band in particular, electricity is generated in the brains and muscles of the players which operate the instruments. That is then converted back into strings of electricity via amplifiers and mixing desks. Then that is saved onto computers; where still more people generate electricity in their brains and muscles, to operate and manipulate the data. That is then sent out via vast distribution networks, which might involve the physical production of storage devices; where it is then played on some sort of music player and possibly amplifier system. It is then converted back into strings of electricity when the sounds strike people's ears, before those electric strings travel into their brains.
All along that journey, which might include many hundreds of relatively mundane and boring steps, are all powered in some way by the flow of electrons and governed by that crudely simple law of V = I R.
I come from a generation of people who remembers the time before the internet and when a telephone was a thing that plugged into the wall. My parents' generation can remember a time before television and my grandparents' generation could even remember a time before radio. I suspect that you would be hard pressed to find anyone living on the planet now, who can remember a time before there was electricity. The World's Fair in Chicago in 1890, was remarkable not because of anything particularly on display there but because of the thing that made it possible to display anything at night. The World's Fair in Chicago in 1890 was really the first major scale use of electric lighting.
The 20th Century which might well prove to be the most remarkable century for a very long time, was the first century in history where people could gain access to power by simply plugging something into a wall. The steam engine may have ushered in the Industrial Revolution but it was electricity which really ushered in the modern world. The valve, transistor and the integrated circuit, did more to transform the way we move, are entertained, communicate, do business, do work, and live our lives, than any other set of physical inventions in the history of the world and yet they're all governed by the simple law of V = I R.
I am willing to suggest that of the four fundamental forces of the universe (gravitation, electromagnetism, the weak nuclear force, and the strong nuclear force) that electromagnetism is perhaps the most elegant of them because it is the purest to explain. We knew about gravitation first because but the maths were messy and the two nuclear forces have even messier mathematics but electromagnetism has one of the simplest to understand and remember of all the equations and identities in science; and I think that that's beautiful.