Re: Using the RM for ADTs
Date: Wed, 8 Jul 2009 07:42:31 -0700 (PDT)
Message-ID: <cc914f85-fc4c-438b-97c8-89067eb5f015_at_g1g2000pra.googlegroups.com>
On Jul 7, 11:43 pm, "Brian Selzer" <br..._at_selzer-software.com> wrote:
> Here is a case in which what defines something is how it stands in relation
This idea is fundamental to the axiomatic approach to mathematics.
One can draw a parallel with the natural numbers which can be defined
using the Peano axioms. This treats the natural numbers as an
abstract set. As such one could use abstract identifiers for each of
the elements, and define them though their relation to each other.
ISTM that we don't use abstract identifiers for the natural numbers
because we don't need to. We can instead encode them using a physical
representation that maps to the number of successor operations from 0.
Evidently "tricks" like this cannot be used in more complicated
examples.
> ...,it is intuitively obvious
I disagree. Circuits may contain a lot of self-symmetry. One can
investigate this mathematically by considering the group of
automorphisms in the obvious way.
Some circuits have more symmetry than others. For example, one can
partially break the symmetry by changing only one of the resistors.
This affects the group of automorphisms.
Received on Wed Jul 08 2009 - 16:42:31 CEST
> to other things rather than just a collection of properties.
> that each component or node should still be distinguishable from all other
> components and nodes in the same template;