Re: must numbers in maths be unitless

From: Shmuel (Seymour J.) Metz (spamtrap_at_library.lspace.org.invalid)
Date: 01/27/05 

Date: Thu, 27 Jan 2005 00:29:21 -0500

In <4289e36c.0501260738.2625ac43@posting.google.com>, on 01/26/2005
   at 07:38 AM, transluuuuucent@yahoo.com (Johnny) said:

>I don't even know what I'm asking.

You're confusing a physical measurement with number. A physical
measurement gives the value of a physical quantity in some coordinate
system, and the associated number depends on the coordinate system.
But products or rations of physical quantities might be unitless, and
thus representable by pure numbers. Thus while if x and y are lengths
it is meaningless to compare x^2 to x or y^2 to y, it *IS* meaningful
to compare (x/y)^2 to x/y.

>What should I read?

Google for dimensional analysis. I'm not familiar with the literature,
but there's bound to be a lot. 

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