A 100-Year-Old Physics Problem Has Been Solved

My simplistic understanding is that a resonator has a lot of energy bouncing around inside. It could be magnetic fields and electric fields in an RLC circuit, light in a Fabry-Perot cavity, sound in an organ pipe, whatever. A little bit leaks out. The less that leaks out, the higher the Q.

A sine wave of infinite length has zero bandwidth. A shorter piece of a sine wave has a wider bandwidth. The shorter the "coherence length", the wider the bandwidth. In a low-Q resonator, a sine wave signal escapes sooner, has a shorter coherence length and a wider bandwidth. This is basic Fourier analysis.

There are other ways than using a resonator to store a signal that obviously violate the Lorentz time-bandwidth reciprocity criteria. A delay line (electrical, acoustical, optical, etc) can store a signal with a bandwidth that does not depend on the delay.

I guess it depends in this case whether the device is a resonator or something else.

Show me some experimental confirmation, and then I'll be interested!

When he said the " Q " factor, I thought he meant this :

I see this as a big deal firstly in telecommunication.

It may play a role also in laser power amplification, and in some other fields, including detection of light signals that are so low they are in the noise limit.

That latter sounds as much like astronomy as communication...

OK, I left off astronomy, but in that field, one had best know how to dig those signals "out of the dirt".