Corresponding to the title, I open with what is a not as simple a question as it at first may seem.
"If a tree falls in an empty Forest, does it make a sound?"
I have recounted this question then further debated the answer with many friends and family who all straight away answer yes of course it still makes a sound. Away from the belligerence in the quick reaction, it echos what I'm sure many people would see as none other than the obvious answer.
First let me explain that this question, although wasted on my and many subjects, is supposed to make you think and ponder the question, thus exercising the mind.
Many angles can be taken to try and answer this brain ache all of which I will touch on.
Firstly lets look at it using physics and also definition. Personally I thought physics would prove my doubters correct and that it would make a sound as I was looking at it philosophically and touching on quantum mechanics and possibilities. But to my pleasant surprise, physics is also on my side.
The dictionary definition of sound using physics is - In layman's terms if no one was around to hear the vibrations caused by the falling tree thus turning them into sound then they would just remain vibrations in the air very quickly fading.
'the sensation produced by stimulation of the organs of hearing by vibrations transmitted through the air or other medium.'
An interesting way to further explain this is if you were to put a deaf person near the tree. Although they would feel the vibrations and it would cause an effect, it would still not become sound as there auditory system and hearing organs do not function and could not process the vibrations.
The way my mind works my thoughts were more of, well do you really know? No, nobody really knows. It is presumed that the tree would make the "thud" but unless there, no one can ever be certain. Something that is called a 'super state'.
A super state is best described using the thought experiment of Schrodinger’s cat. To quickly describe this, in 1935 Schrodinger (an Austrian Physicist) came up with a thought experiment to try show the absurdities in quantum mechanics. You would place a cat in a large sealed box with some potentially radioactive particles linked up to a machine. This small machine could detect if one of these sub atomic particles decided to become radioactive. If it did (something of which there is a 50/50 chance of happening) then a hammer would break a vile of cyanide and the cat would die. If not then the cat would survive. The point of this is that as no one knows what has happened, the cat is both dead and alive. So it is in a super state. This video goes into more detail Schrodinger’s experiment.
So in conclusion, from every angle looked through the only possible answer in my opinion to the conundrum is that no the tree did not make a noise if nobody was there to hear it or in any respects even know whether the tree had even fallen.