The continuous emission spectrum still peaks at certain visible wavelengths, no matter if no one is there to see it. More like a discussion of spastics!
In this case the question wasn't about whether anyone was there to see it. It was about the color of an object in the absence of incident light. But that reminds me (thankyou). Another camp suggested that the color of the orange in the dark is infrared - ie the peak of the orange's emission spectrum (assuming it's at room temperature). No, semantics. We can discuss CP if you like, but not in this thread.
You forgot to insert the sound between two layers of impenetrable silence, to which the proceeding layer is snuffing out the sound of the fall. It gives a whole new perspective to the image of a tree falling and progressively bearing its full weight to the ground.
Shush, I'm trying to hear . . . . Before reading other responses I offer the following. If what you mean by sound is the motion of air molecules strking the ear drum of an organic being and that all such eared organic beings were not around the falling tree, then by definition there would be no sound. This does not change the physics of the problem as there would still be significant amounts of vibrating air generted by the tree crashing to the ground that would spread outward from the various points on the surface of the tree trunk. All physical entities, eared or otherwise, within the effective "blast radius" of the falling tree would sense the effect of air vibration in some manner, depending on the physical structure of the entity under consideration. Effective blast radius here is defined within a maximum distance from the tree where any measurable affect of vibrating air on that entity was recorded or recordable, other than the tree itself, such as bark from other trees, leaves, hair, liquids, dirt, gasses etc. If outiside the blast radius (which is different for different substances of course) then no sound.:shrug:
