Saturday, April 24, 2010

Hella-cool


Sometimes as a wee tad, when my teacher's voice began to drone on interminably, I'd turn listlessly to the inside cover of my arithmetic book. What peculiar information I'd find there! How many pecks in a bushel! How many feet in a rod! Dry ounces and fluid ounces. Furlongs, fathoms and nautical miles.

The conversions were all so arbitrary -- fascinating to my immature brain -- and the units so wonderfully named. But the system was impossible to grasp in any manner other than by sheer memorization. Who, for example, ever decided that there should be 437.5 grains to an ounce?

On the other hand, set out beside these weird measurements was a different system. The metric system, of course, but at that age no one had ever explained the metric system to us. I knew about feet and miles and quarts and pounds, just from daily life. I didn't know about meters and liters. The conversions from English measurements to metric, and vice versa, were even weirder than those within the English system. But the metric system, viewed within itself, was beautiful -- everything in multiples of ten.

And even more fascinating to me -- novice connaisseur of words that I already was -- were the prefixes affixed to units of distance, weight, and everything else. Deci-, centi- and milli-, as things got smaller. Deka-, hecto-, and kilo-, as they got larger.

That was the extent of the metric system inside the cover of my fourth grade math text. Later, I learned even more beautiful terms. Micro, nano and pico -- for a millionth, a billionth, and a trillionth. Mega and giga for a million times larger and a billion times larger. Today, of course, even cheap computers have gigabytes of memory.

And despite education in physics, that's really where my knowledge of metric nomenclature remained. Until today. This week's edition of the Economist points out the usefulness of two additional terms. While "gigameter," for example, would be 109 meters, a "yottameter" would be a much greater distance -- 1024 meters, or 1015 gigameters. Similarly, at the other end of the scale, a "yoctometer" is 10-24 meters -- a fairly short distance, by anyone's reckoning.

Why would anyone be interested in a "yocto-anything"? The actual subject of the article was experimentation that has permitted scientists to measure a tiny force of only 174 yoctonewtons. A "newton" is defined as the amount of force needed to accelerate a mass of one kilogram at the rate of one meter per second per second (although the Economist -- a British rag addicted to typically English definitions of measurement -- whimsically describes the newton as the approximate force exerted by the earth's gravity at the earth's surface on one of Sir Isaac Newton's apples).

"Yocto" also is useful in measuring mass. A proton has a mass of about 1.26 yoctograms.

So far, yocto and yotta mark the upper and lower limits of the metric system. No one has any need for a unit representing 1/1000 of a yocto-anything, or 1,000 yotta-anythings.1 Linguistically, however, as the Economist observes, we're ready if science creates the need. Terms for 1027 and 10-27 logically should be based on the Greek root "ennea" (meaning "nine" times three zeros).

But an undergrad from California (where else?) has reportedly started a campaign to scrap the Greek nomenclature when we reach that next level, and adopt the prefix "hella" for 10 to the plus or minus 27th. Cuz, dude, that would be either hella big or hella little.

Hella good idea, I'd say.

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1Fans of humongous numbers will recall, of course, the proposed "googol" as representing 10100, or 1 followed by 100 zeros. And the later refinement, the "googolplex," defined as 1 followed by a googol zeroes. (Mega-behemoth Google derives its name therefrom.)

Since there are only about 5 x 1087 elementary particles in the known, observable universe, the googol -- let alone the googolplex -- seems of limited utility. (Estimated particle numbers, courtesy of Wikipedia.)

My desire to fully describe large-number nomenclature requires that I also acknowledge the Facebook page, "Shitload" is a Standardized Unit of Measurement," to which 847,456 fans now subscribe.

3 comments:

Zachary Freier said...

In advanced science, there are examples of numbers that fall outside the E-24 to E24 range (E# is shorthand for 10^#). Planck's constant, which shows up all over the place in quantum mechanics, is 6.626E-34 J*s (Joule-seconds, which is an incredibly abstract unit, but I digress...).

Even those very large or very small numbers that could be expressed using the Greek prefixes are generally not expressed that way by scientists. If something is 10E24 meters away, most scientists would not call it a yottameter; they'd just say "10 to the 24th meters". The prefixes, after all, are only useful insofar as most people can remember them. The basic ones (generally from milli- to kilo-) are well-known enough that they are often used. Beyond that, though, it's pretty rare to actually see them used... (A notable exception being nano-, because it sounds cool, and is a useful scale for things happening on the atomic/molecular level).

Rainier96 said...

Excellent point. And I hasten to assure everyone that I usually think in terms of scientific notation myself, as do most people, scientists or not, for the reasons you state. Also, if you're planning to do something with the numbers -- multiply or divide them, for example -- it helps immensely to have them handy in exponential form.

As you say, not only would most scientists not say "yottameter" -- virtually none of them would.

How did your own scientific career work out spring semester?

Rainier96 said...

For those of you interested in Zachary's on-going academic career, he finished up his sophomore year at Colorado/Boulder with his first grades below an A-. (Gasp!) He received B+'s in physical chemistry and organic chemistry. (Notoriously difficult subjects, filled with pre-med students desperate for A's.)

Organic Chemistry 2 - B+
Organic Chemistry 2 Lab - A
Physical Chemistry for Engineers - B+
Chemical Engineering Fluid Mechanics - A
Introductory Logic - A