[sdiy] Is everything digital?

[Magnus Danielson]

From: Seb Francis <seb at burnit.co.uk>
Subject: Re: [sdiy] Is everything digital?
Date: Sat, 14 May 2005 17:03:28 +0100
Message-ID: <42862150.9080007 at burnit.co.uk>

> Paul Schreiber wrote:
> 
> > The prpoer statement is "Everything is quantized." Even "continuous 
> > analog" voltages are quantized, albeit VERY small steps (like 10^-18 
> > V). Even temperatue and time are quantized, because nuclear events on 
> > which they are based are themselves quantized.
> >
> I'm sure there are some quantum physicists who would disagree with this 
> statement and would perhaps say that these quantisations occur more by 
> virtue of the observer (or way of measurement) ..
> 
> In any case, all these tiny events, particles, etc. are nothing more 
> than theoretical models which scientists have made up to try to 
> understand and predict what's actually going on at such tiny levels.

Many quantum phenomense have been observed fairly directly, but the whole field
of quantum mechanics came about since continous models could not describe at
all what was going on. Onces the pre-cursors (Planck) where there, a few
theoretical steps one started to make measurements. The spectral lines where a
good hint in themselfs. They could be put into strict mathematical formulas,
but the reasons for them being the way they was and what the magic constants
and limts where took quite some exercises to break into. Peculiarities like
positrons didn't really help either I might add.

About the quantum steps on voltages, I tend to say a distinct no. If you take
the metal plates again, but up a charge of one electron, check out the range of
voltages you can get by varying the distance between the plates. These
distances needs to be quantized in order for the voltages to be quantized, but
if the distance is continous, so will the voltage. Only certain very specific
cases have quantized distances, such as "orbit radius" (a falacy name at the
best) of electrons in an atom, but I have yeat to see a proof for quantized
distanced in a general sense. There are many "normal" pheonmenas which can
become quantized under certain curcumstances, but this does not mean that they
are quantized in a general sense, just that they _can_ have quantized
properties. Also, just becasue a characteristic measure can be shown to be
quantized, it does not have to be a linear quantization, but just a fixed set
of steps in value.

So, for the most part, it *IS* analouge. ;O)

Cheers,
Magnus