[PatrickHenry]

Doesn't this whole "green" problem boil down to the classic "if a tree falls in the forest and no one's around to hear it" question? In the case of the lonely tree, it certainly falls, and the air vibrates, but "sound" is a reaction in a human brain. No listener, no "sound." Or, to tie this in to the "green" question: no viewer, no green. However, I'm probably missing a bunch of subtleties, as I often do in such discussions.

[Alamo-Girl]

Er, if I may...

Doesn't this whole "green" problem boil down to the classic "if a tree falls in the forest and no one's around to hear it" question? In the case of the lonely tree, it certainly falls, and the air vibrates, but "sound" is a reaction in a human brain.

Sound waves are recorded in the cosmic microwave background at the moment the universe had cooled enough for photons to "decouple" from electrons, protons, and neutrons, atoms formed and light went on its way.

There was no physical organism to hear that sound yet there you have it - proof that sound exists even if noone hears it.