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Energy, etc



Let me please chime in here, Leigh and I are very close in this -- we may
quibble re wording but.....

Bill-

I don't quite understand. Here's where my brain-fuzz is located:

In a short pulse of laser light, energy is located in the propagating EM
radiation, OK?

NO. "Energy" is not "located" It does not "flow". It is not like water,
as Leigh says. Energy is a property of a system. You would not say that
the "blue" of a blue object is "located" anywhere would you? Not a perfect
analogy (none are) but close.

Most of our physics language is only to say enough about a system to make
some sort of calculation and from there some sort of useful
prediction. Physics has long since stopped trying to describe reality --
at least precisely.

The danger I have tried to mention here is that we often come to think of
our language as some sort of reality --- this because we use phrases
frequently enough that we forget to think just what it is we are saying --
like some sort of mantra. Our misuse of the language may suffice at times,
but we come to assume that the faulty language is _always_ helpful.

It is not. And this fact rears is head when we launch into some esoteric
discussion without clearly thinking through what we are saying,

Jim

Jim Green
mailto:JMGreen@sisna.com
http://users.sisna.com/jmgreen