It’s been a long day

October 8, 2009 at 7:12 pm (Particle Physics) ()

So I’m going to post a little oddity from my past, and my friendship with Vorex.  This was written early in the morning while I was at college.

> Have you noticed that silence is always said to decend?
>
> It never comes up out of anything, it always falls down as if from the sky. Evidently silence is more dense than air.

Now you’ve done it.  You’ve gotten me thinking.  Let it be on your head.  😛

Actually, you’re right – silence is more dense than air, at least in some respects.  When a sound is made, the particles through which it passes are excited, the energy of the sound wave causing them to vibrate.  The increase in kinetic energy cannot be a 100% efficient conversion, and the energy lost in the transfer is expressed as an increase in temperature, or thermal energy.

It is a well-known phenomenon that, as a substance heats, it expands.  While this is not very effective on most solids, it is observable with liquids and gasses, where the bonds between particles are weak enough that less energy is required to expand them.  When a substance expands, its volume increases, given that it does not have an external boundary.  When it does, the pressure will increase instead.  But, as free air doesn’t have such a boundary, we can neglect that issue.

As density is determined by taking the mass of a substance and dividing it by the volume, an increase in the volume results in a decrease in the density.

Thus, when somebody heats a substance, the density decreases.  As we have established that speaking heats a substance, it is a logical step to conclude that, all other things held equal, noise results in a decrease in density.

Thus, silence, as an absence of noise, is has a higher density than air that has sound waves passing through it.  As such, the air higher in an area – being both slightly cooler naturally, and above soundwaves, will be denser than the air sound is being made in.

Thus, it can be logically extrapolated that silence descends.

And, in addition, it can be extrapolated that I *really* shouldn’t be allowed to think before I fully wake up in the morning….

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