Re: convert light into energy

[Leigh Palmer <palmer@SFU.CA>]

> Leigh Palmer wrote:
>
> > ... Energy is not a thing; it is not real. It is just a number
> >  that we calculate by canon. ...
>
> The same is true for temperature, force, speed, acceleration,
> mass, charge, angle, number, wavelength, color, etc. We invent
> concepts to describe things (real objects) and their interactions.
> How can a physicist disagree with this?

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. My point is far from semantic, I hope to
tell you! I also have a problem with charge, which I have admitted
to my own mundane realm of real things. Charge is locally conserved,
a really big point in favor of its reality.

Leigh

(Quintessentially material - did he really say that (snicker)? Yeah,
I said it, but I take it back. It's so good I have to leave it for
all to see, however. Of course I should have said "fundamentally
material". English is fun!)