Earlier quoted context omitted.
Speed of sound in vacuum The speed of sound in vacuum is the speed of sound in a perfect vacuum. In a perfect vacuum, there are no molecules to support the propagation of sound, so sound cannot propagate through it. This speed is usually referred to as "the speed of sound" and is usually denoted by c, which is the standard notation for the speed of light. In fact, the speed of light is very close to the speed of soun…
> the speed of light is very close to the speed of sound in a perfect vacuum I am not knowledgeable in physics but this looked wrong to me until I reflected that in a near vacuum, the elasticity is very high and density nearer to zero. So per the equation of speed of sound, (square of ( elasticity / density ) ) is extremely high, so near the speed of light. Not so bad.
I think in the future humans will need to invent secret languages, not digitized or shared with computers in order to be able to filter wrong but convincing information.