Talk this Friday 18th September: What Really Is a Radio Wave? With John G8DGN

From Electricty and Magnetism to Quantumn Fields: Friday 18th September 20:00-22:00

Starting with the history of our understanding of electricity, this talk follows the remarkable journey from the first observations of electrical phenomena to our modern picture of the electromagnetic world. We’ll look at the basics of electricity and circuits, the intimate connection between electricity and magnetism, AC theory and oscillators, and how these lead naturally to Maxwell’s electromagnetic theory and the operation of antennas.

But what actually happens when a signal leaves an antenna? How does electromagnetic energy propagate through what appears to be empty vacuum, and what is it that is oscillating?

Finally, we’ll take the journey beyond classical electromagnetism into the quantum world, exploring photons, quantum fields and the modern view of electromagnetic radiation.

Along the way, familiar concepts from amateur radio will be connected to the deeper physics that ultimately explains what a radio wave really is.