buck%NRL-CSS@sri-unix.UUCP (01/10/84)
From: Joe Buck <buck@NRL-CSS> ... should be based on universal physical constants. One possibility is a system of units based on c (speed of light), h (Planck's constant), m (mass of electron), and e (charge of electron). In this system, the unit of length is h/(mc) and the unit of time is h/(mc^2). Of course, all these units are very small, we would need a multiplying factor. These factors should be powers of two, rather than ten; different species will have different numbers of fingers (or whatever), but any species that builds computers will deal in powers of two, as it's simpler to build devices with two states than devices with more. Alternatively, G (the gravitational constant) and/or a0 (Bohr radius, the radius of the electron's orbit in the Bohr model) could replace any of c, h, or m. I'm sure there are other possibilities. The Pioneer 10 picture uses the wavelength emitted by the spin-flip of monatomic hydrogen - about 21 cm - as a unit in explaining the height of human beings.
Reynolds%RAND-UNIX@sri-unix.UUCP (01/13/84)
There have been some messages lately about the possibility for non-arb- itrary units of measure. For time and distance this is a hard problem, but I was suprised when some one mentioned that you have the same dif- ficulty with angle measures. (This came up during discussion of parsecs -> seconds of arc -> degrees -> radians -> ...) Well 360 is a pretty random number, but the idea of "a number a little bigger than 6 and a quarter" is ridiculous! The obvious value is 1, the name of this unit is "revolutions", one degree = 1/360 of a revolution. That unit is both completely non-arbitrary (no funny constants) and universal (makes sense no matter how many fingers (or whatever) you have). This approach is very useful in computational geometry, and is used by several computer graphics / computer geometry systems (including my favorite: ASAS).
giles@ucf-cs.UUCP (Bruce Giles) (01/17/84)
What base do you use for your logarithms? 10? I admit that pi is not exactly a number which rolls fluidly off the tongue, but it is used for a very simple reason -- things come out a lot cleaner with it than with any other number. Sure, for `average man in the street' applications revolutions is a nicer unit, but for any real analysis in mathematical physics pi, e, and all of the other common transcendental numbers greatly simplify the work. In fact, I would seriously question if any race (even one using symbolic mathematical programs) could attain the level of technology required for the entire discussion on universal units to have meaning. Quite simply (yes, I like that word :-)), they would get bogged down with all of the extra terms introduced by using other constants. Finally, in my general relativity course we renormalized all units into meters, using the following conversions: speed of light = c = 1 gravitation constant = G = 1 Boltzmann constant = k = 1 unit of planar angles = radians (2 pi radians / circle) unit of solid angles = steradians (4 pi steradians / sphere) unit of temperature = degrees Kelvin And for an exercise we found the renormalizations used in advanced quantum mechanics, which was the same as above except that Boltzmann's constant was replaced with Planck's constant. Remember, the people who would actually make the contact have already spent nearly a century with their renormalizations, and they were not picked arbitrarily. Bruce Giles --------------------------------------------- UUCP: decvax!ucf-cs!giles cs-net: giles@ucf ARPA: giles.ucf-cs@Rand-Relay Snail: University of Central Florida Dept of Math, POB 26000 Orlando Fl 32816 ---------------------------------------------
gds@mit-eddie.UUCP (Greg Skinner) (01/19/84)
Why not have a universal system based on 42, since it is the Ultimate
Answer? :-)
--
--greg
{decvax!genrad, eagle!mit-vax, ihnp4}!mit-eddie!gds (UUCP)
Gds@XX (ARPA)Heiny.henr@Parc-Maxc.Arpa (01/26/84)
From: Chris Heiny <Heiny.henr@Parc-Maxc.Arpa> "Why not have a universal system based on 42, since it is the Ultimate Answer? :-)" Or better yet, 47. Since 47 is the most common number in the universe (or so I am told), it would be much more obvious a constant to those who don't know the Answer yet. Chris PS Is anyone else out there in SFLoversLand acquainted with the 47 theorem? I used to have the proof for above fact, but cannot find it.
FAUST%MIT-OZ@MIT-MC.ARPA (01/31/84)
From: Gregory Faust <FAUST%MIT-OZ@MIT-MC.ARPA>
Stop, Stop, your both wrong. Neither 42 or 47 is the right number
on which to base the universal system. The correct number is
obviously 17; the most random number. What better number on which to
base a totally random concept?
Greg