Re: How Archimedes' Solar Death Ray Could Have Worked

Wasn't it who wrote:
>
>Dr John Stockton wrote:
>
>> There is a general theorem to the effect that ordinary optics cannot
>> increase the apparent surface brightness of a source; look it up.
>
>I'm not sure why that would be? Let's say you turn the whole Earth
>into a mirror and focus it all on point ... surely there would be more
>than enough light hitting that point to raise it to a temperature much
>hotter than the surface of the Sun? What am I not getting?

If the focus point were hotter than the Sun, then heat and light from
the "hotter than the Sun" point would go back through the mirrors and
warm the Sun up slightly. That would be a violation of conservation of
energy as well as the second law of thermodynamics.

--
Mike Williams
Gentleman of Leisure
.

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