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Re: My comments

This page is part of the web mail archives of SRFI 77 from before July 7th, 2015. The new archives for SRFI 77 contain all messages, not just those from before July 7th, 2015.

Bradd W. Szonye wrote:
>> While they seem silly for small integers, inexact integers make sense
>> for huge values. For example, people often round huge integers to the
>> nearest million or billion. An even better example: Avogadro's number
>> is an integer, but it should not be represented as an exact integer,
>> because its exact value is unknown.

Thomas Bushnell BSG wrote:
> What makes you think Avogadro's number is an integer?

Because there's no such thing as half an atom of carbon. Furthermore, as
you mentioned yourself, the error in measuring the canonical gram is
much larger than the mass of an atom, so why /wouldn't/ it be an
integer? Indeed, if we were to switch the gram from a sample to a more
fundamental definition, I would expect something like "1/12 the mass of
one mole of carbon-12," with the mole fixed at an integral number of

> Oh, and that assertion I made that there are an integral number of
> atoms in a sample at a moment in time: not really true.  After all,
> the atoms are evaporating and condensing on to and off of the surface
> of the sample all the time at an exceedingly high rate ....

While it's true that it's (practically and theoretically) impossible to
count the number of atoms in a sample, that doesn't make the number
non-integral. It simply makes it inexact.
Bradd W. Szonye