Do I always have to write "self." ?

Charles Hixson charleshixsn at earthlink.net
Thu May 4 16:06:46 EDT 2000


I don't really recall, h_bar may indeed be a dimensionless quantity.  There
are a few of them.  But c has the dimensionality of velocity (i.e., delta d
/ delta t).  Exactly which units you choose to use are up to your
convenience.  If you choose them appropriately, c will equal 1 * (3,000,000
m)/(1 year), which specifies the ratio that your units must have in order
for the value of c to equal 1.

Andrew Dalke wrote:

> Samuel A. Falvo II wrote:
> >*I* don't think
> >Hungarian is nasty -- I see it as a tool a programmer can use to keep
> things
> >straight in his head, and on paper, precisely as a Physicist would use
> units
> >to keep things straight in his/her head.
>
> But particle and nuclear physicists (at least) don't use units  :)
> There are a couple of notations where basic physical constants are
> set to 1, eg:
>   c == speed of light == 1
>   h_bar == planck's constant/(2 pi) == 1
>
> This reduces the need for carrying around a lot of extra constants,
> like c**3/h**2.  When the calculations are finished, you then say "and
> because the final terms must be units of spam, we add eggs**3/viking".
>
>                     Andrew
>                     dalke at acm.org




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