The medium of the "Vacuum" is electromagnetic radiation

[budrap00]

From a Quora answer:

[HanDeBruijn]

A decent reference might be Wikipedia's Speed of sound.
The formula that comes most nearby for the speed of a sound wave is

$$ c = \sqrt{\gamma\frac{p}{\rho}} \quad \mbox{equivalently} \quad V = \sqrt{(\gamma P/\rho)} $$

where $\gamma$ is the Heat capacity ratio. Theoretical values are around $\gamma=1.4$ . So I don't understand where a value of $\gamma=2$ comes from in the first place. And of course, when considering values for pressure and density in a vacuum / aether : how are these observed / measured ?

Nice demonstration that the medium of the “Vacuum” is electromagnetic radiation.

???

[budrap00]

Yes, what the pressure term means or where it comes from is not clear. It might just be a model fitting exercise. However the medium of the vacuum is observed to be electromagnetic radiation, so...

[genotics]

Han is spot on with his reference. I would only suggest that you take a look at the Prandtl-Glauert transformation (see Wikipedia) which relies on the Prandtl-Glauert factor. Basic laws of electromagnetism have analogous laws in hydrodynamics, e.g., Biot-Savart. See https://archive.org/details/fundamentalsofhy0000tiet/page/206/mode/2up?q=biot&view=theater

Some have concluded that electromagnetism is a gas phenomenon, and that particles are vortex structures.