The Subsonic Whale

People are often unaware what is meant by the term "Subsonic Noise". It's just another term for vibration. And there are all kinds of things producing it: People, Cars, Elephants, even the natural "tidal"-pulsation of the earth itself (our Moon's gravity warps the Earth, and its oceans and atmosphere to an relatively significant degree).

Our sense of hearing operates on what we might call the Sonic level (Hence SUBsonic--i.e., just outside our normal range of hearing.

We sense ALL forms of noise through our bones (we wouldn't be able to hear ANYTHING without that highly specialized trio of tiny bones in our inner-ear: often called the Hammer, Anvil, and Stirrup).

However, people with porous bones (osteoporosis) have an additional acoustic phenomenon of having sounds projected into bone cavities (if you've ever noticed a strangely disconcerting loss-of-hearing when you have a cold...that's usually the result of your sinus cavities being full of viscous fluid...its like what you hear underwater).

Anyway, my point is that osteoporosis actually INCREASES a person's sensitivity to vibration because it creates natural acoustic cavities (little auditoriums) at the very topographic centers of a person, making SOME ELDERLY PEOPLE extremely sensitive to rumblings of all kinds...naturally so.

Now the tidal "rumblings" of the moon are at such a low frequency as to go totally unnoticed (except for the rising and falling of the tides--which have enough mass and fluidity to be visible to humans [as opposed to those forces working inside the Earth..which aren't readily apparent to us until an earthquake or a volcano hits], but the perceivability is a function of observing those trends over long scales of time: therefore those vibrations, too would classify as Subsonic Noise. Just not the kind HUMANS perceive.

To blatantly steal an idea from Star Trek IV: that might mean that the perception of perturbations of the earth, Moon, Sun and planets might be perceivable to large, long-lived animals far-better than they are by humans. Which makes far more interesting this passage from the book of Genesis:

http://www.biblegateway.com/passage/?search=Genesis%201

Funny how words have so many different flavors of meaning depending on the order in which you read them. ;)

--mattergy

Addendum 5:00 p.m. PST
As I considered even more deeply how profound what I was saying actually was, I happened to be reminded that without a cohesive and relatively permanent method of sharing complex ideas, without the invention of interchangeable conceptualization--i.e. sifting the symbol systems that have been passed down lead us to the idea of actually measuring the metering of language to "discover the secrets within it"...hence Mathematics via Language.

Without Leonard Nimoy's fanciful Star Trek IV, I might have never gotten the idea that music has a whole different beat for a being whose neural networking relied in part on large sea Mammals...but even MORE on how good the idea is for coming up with higher-level languages that have a way of converting the symbols we use from ACTUAL EVERYDAY EXPERIENCE into SCORED LISTS OF LIFE'S LITTLE SYMBOL-ONE-LINERS. HENCE THE HISTORY WE HAVE ACTUALLY PHYSICALLY DISCOVERED in CASPIAN, AEGEAN, RED, NORTH, CHINA, and BLACK SEA cultures.

Addendum 1/7/08
There really isn't ANY advantage to having porous bones...the effect I'm talking about is actually a noise-canceling effect in some ways, because UNLESS a frequency is naturally echoed in those cavities, it will actually be REDUCED. In this case, a person's bones behave more like porous acoustic foam, rather than like solid crystals that carry resonant frequencies almost PERFECTLY


Addendum 2 1/7/08
I guess I'm not enunciating the idea that reducing the noise from our own body DOES allow SOME advantage, if you're listening for very faint noise (cooling is a common method of molecular noise-reduction for MANY applications [like some telescopes and lasers that require focus unperturbed by random molecular noise]) but porous bones are BRITTLE bones, and nobody wants THAT.

In this case, you'd expect that genuine sensation of large-scale, low-frequency noise would be more easily perceived in caverous liquid-filled expanses...think whale.