Re: convert light into energy

[Ludwik Kowalski <KowalskiL@MAIL.MONTCLAIR.EDU>]

I am comfortable with thinking that mass, and charge,
and strangeness, etc. are attributes rather than things.
Yes, all physical objects (things) are characterized by
certain m, certain +q, certain -q, certain temperature,
certain reflectivity, certain conductivity, etc. The
attributes are real, as real as the objects themselves.
In that sense I do not disagree with Leigh and JohnD.
Leigh said mass is real, John said energy is also real.

What is the purpose of making some attributes more
real, or less real, than others? I see no clear pedagogical
advantages, or disadvantages, in emphasizing such
nuances. Any measurable characteristic of an object is
an attribute, not the object, in classical physics.
Ludwik Kowalski

Leigh Palmer wrote:

> Whoa! I think you go too far. While "mass" may not
> be real, matter is quintessentially material, and mass is
> pretty close to synonymous with matter - quantity of
> matter, I'll grant you - but saying mass isn't real is of
> no help in explaining the world to students; it is at best
> a semantic point.