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Can I film the police with no reason?
- Thread starter GingerBeerMan
- Start date
It's an interesting debate.
Perception is a great thing. If I give you a box, and tell you there's a pound coin in there, but you cannot perceive the matter to be a pound coin, is it really something, since you cannot see it?
Anyway back to the senseless banter, please. Police...
In layman's terms, what makes LIGHT the exception to this rule? Surely if it cannot be seen, it cannot be proved to be there?
Bold Seagull
strong and stable with me, or...
Of course colour is a different matter, and like sound it is a perception. Light is electromagnetic radiation (EMR) which travels through space carrying radiant energy. Visible light from the EMR is what we are able to perceive. Without our eyes, green doesn't actually exist, it is simply a wavelength of the EMR.
Colour is basically matter the absorption all the other wavelengths of the EMR. A leaf is green because it has absorbed all other EMR wavelength frequencies of the visible light spectrum other than green which has bounced off. Black is the absorption of all light.
Like sound or smell, without our perception colour doesn't exist.
Colour is basically matter the absorption all the other wavelengths of the EMR. A leaf is green because it has absorbed all other EMR wavelength frequencies of the visible light spectrum other than green which has bounced off. Black is the absorption of all light.
Like sound or smell, without our perception colour doesn't exist.
Because light doesn't need to be perceived, seen or observed to be there, it is emitted and absorbed by charged particles.
Bold Seagull
strong and stable with me, or...
I've sort of answered that, but visible light is actually a small part of Electro Magnetic Radiation which is a form of energy emitted by charged particles. The important part here, is that EMR will travel in a vacuum at precisely the speed of light. It is a universal constant, it exists regardless of perception.
Our experience of our own visible part of EMR, i.e. what we see, is however what we perceive, hence my post on colour.
Interestingly, leaves and grass on another planet might be purple, because they might use a different part of the light spectrum for photosynthesis.
Bold Seagull
strong and stable with me, or...
We can't of course continue without reference to Schrodinger's Cat....
Kalimantan Gull
Well-known member
hmmmm. dog whistles make sound to the dog, but not to the person. Likewise a tree falling on the forest may be heard by me 1 mile away, but not by you (or vice versa, depending who has the more sensitive ears). Therefore it is argued that whether it is sound or not depends on the receiver. That's not a very satisfactory way to resolve this, and relies on a completely human-centric approach to the universe, whereas sound is surely a physical property of the vibrations themselves. A vibration is a vibration, whether or not it is observed, so therefore a sound is a sound is a sound, whether or not we have the tools to hear it?
Kalimantan Gull
Well-known member
yes, but isn't that a paradox merely designed to show that matter cannot exist in an either/or state?
A sound is the translation of the vibration. A sound is only a sound when heard.
Kalimantan Gull
Well-known member
But doesn't that fall apart when two people are present, and only one can hear it because his ears are better.
"Listen to that amazing sound".. "I can't hear it, therefore it is not a sound and you are talking bollocks".."but I can hear it and it is beautiful".. "There is no sound, therefore you are mad"... and so on
No, it doesn't.
nwgull
Well-known member
I can confirm that it does, I was sat in my office alone earlier and let a post lunch stinker rip. I love the smell of my own farts though.
Kalimantan Gull
Well-known member
Ok, well i disagree, but
I think of the original paradox as 'if a tree falls in the forest but no-one is there to hear it, does it make a vibration that could be translated as sound?' I've always thought the definition of sound meant just that, and the actual translation of the vibration doesn't seem that important to me, because its not physics, just the ability of the observer to perceive.
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So being a translation of vibration. Is noise, sound? Tinnitus sufferers hear noise in their heads but do they hear sounds? Again when we dream we "hear". You could pass it off as just the imagination but could all sound be this. What you hear could be something completely different to me, our interpretation can be the same due to the way we learn from a young age. Its the same as attempting to describe colour to a person blind from birth.
Nope, a quick grab from Wiki says "sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.[1]"
Note it doesn't say "that is then heard" but strong enough. So the tree would create a sound because the oscillation would still be there.
Bold Seagull
strong and stable with me, or...
'composed of frequencies within the range of hearing' - is the important part. Without hearing, the sound does not exist. The tree falls, it makes all the oscillations / vibrations to create sound, they are all present, but they are not sound unless they are perceived.
Conceptually, based on our reality, then yes of course it makes a sound because we can hear, and we know that the creation of the sound waves can and would be heard, or could be recorded on equipment, however step outside what we are able to perceive, and all that tree is doing is making a load of vibrations through air and matter.