Re: [Vo]:Three Words That Could Overthrow Physics

[Harry Veeder]

I am calling your bluff. ;-)

What is the difference between an explanation and a model?
You have said something substantive about models, but nothing substantive
about explanations, except to say that explanation is not a model.
Or is it just an issue of semantics?

harry
----- Original Message -----
From: "Stephen A. Lawrence" <[EMAIL PROTECTED]>
Date: Wednesday, June 4, 2008 4:31 pm
Subject: Re: [Vo]:Three Words That Could Overthrow Physics

> 
> 
> Terry Blanton wrote:
> > "What is Magnetism"
> > 
> > http://discovermagazine.com/2008/may/02-three-words-that-could-
> overthrow-physics
> 
> The author of the piece wants something that will "explain" "why" 
> magnets do what they do.
> 
> Physics doesn't "explain".  It "models".  There's a huge 
> difference. 
> The "model" of reality which is modern physics includes magnetism 
> and 
> the magnetism in the model behaves pretty much like the magnets we 
> see 
> in the real world.  The model has proven to have valuable 
> predictive 
> power, which is why it's currently in use and considered "more or 
> less 
> correct".
> 
> But the fact that the model seems to behave like the real thing 
> doesn't 
> in any way "explain" why the real thing behaves the way it does.  
> No 
> physical theory ever will.  If the author ever gets to converse 
> with God 
> perhaps God will explain /why/ things are the way they are, but 
> until 
> then, all we've got are models, and the best that can be said about 
> any 
> model is that it acts like the real world within its domain of 
> applicability.
> 
> Consider this:  Nearly all of reality goes unobserved.  Of the 
> parts 
> which are observed, nearly everything which is observed is 
> unmeasured. 
> Our judgment as to the accuracy of physical theories is based on 
> the 
> tiny fraction of observed events for which someone takes some 
> measurements.  Those few measurements, which represent a tiny 
> fraction 
> of the observed events, which in turn represent a vanishingly small 
> fraction of all that takes place in the Universe, are the only 
> "points 
> of contact" between reality and theory.  If a mathematical model 
> agrees 
> reasonably well with that relative handful of measurements, we 
> accept it 
> as "apparently correct"...