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Posted
1 hour ago, altaylar2000 said:

The fact of the matter is that it's just light. Then why don't we see it before it is reflected

You can only see photons that strike your eye. Not before, and not if they go somewhere else.

Posted
1 hour ago, swansont said:

You can only see photons that strike your eye. Not before, and not if they go somewhere else.

Actually, I do not believe in Newtonian anatomy, but if I believed in flying photons, I would ask the same thing: why do we not see them when they fly, but we see when they are reflected

Posted
8 minutes ago, altaylar2000 said:

Actually, I do not believe in Newtonian anatomy, but if I believed in flying photons, I would ask the same thing: why do we not see them when they fly, but we see when they are reflected

I don’t think Newtonian anatomy is a thing, but...

How would you see a photon if it hasn’t interacted with your eye? (If they don’t have to interact with your eye, why does closing your eyelids do anything?)

Posted (edited)
5 minutes ago, swansont said:

I don’t think Newtonian anatomy is a thing, but...

What You described is exactly Newton's theory of vision

5 minutes ago, swansont said:

How would you see a photon if it hasn’t interacted with your eye? (If they don’t have to interact with your eye, why does closing your eyelids do anything?)

I have no idea

_____

What I mean. Let's forget about the question of whether light is particles, we will just talk about light, abstracting from what it is.

If I see a green table, it's because it reflects the green part of the spectrum, roughly speaking. So when I see objects I only see reflected light

Edited by altaylar2000
Posted
15 minutes ago, altaylar2000 said:

Actually, I do not believe in Newtonian anatomy, but if I believed in flying photons, I would ask the same thing: why do we not see them when they fly, but we see when they are reflected

You seem to use some non standard definition of "reflected"?  How would detection of photons require a reflection?

 

Posted
1 minute ago, Ghideon said:

You seem to use some non standard definition of "reflected"?

no, this is the standard. So far, no one has canceled the fact that light is absorbed and reflected, and we believe in Newton or a wave, all the same it all comes down to this

We see the color of objects due to the fact that the object reflects part of the spectrum, and the colors are different because different objects absorb and reflect the full spectrum in different ways

Posted
2 minutes ago, altaylar2000 said:

no, this is the standard. So far, no one has canceled the fact that light is absorbed and reflected, and we believe in Newton or a wave, all the same it all comes down to this

So does that mean that you claim that for an observer in the vacuum of space the sky looks completely black? The sun and stars are only visible if the light is reflected off a mirror?

 

Posted
6 minutes ago, Ghideon said:

So does that mean that you claim that for an observer in the vacuum of space the sky looks completely black? The sun and stars are only visible if the light is reflected off a mirror?

No, it doesn't mean. It has nothing to do with it

Posted
14 hours ago, altaylar2000 said:

The system of notes is based on the fact that a certain frequency is taken, and in the next octave the same frequency, a multiple of two, is considered the same note. However, if we took a different multiplication, the notes would be in different frequencies. This means that objectively the notes are just a convention. Why, then, is it claimed that notes can be heard and distinguished from birth?

Surely the point about octaves is that if you double the frequency you get something that resonates with the fundamental. And if you double it again, the same occurs. So doubling has a real significance, both from the point of view of physics and from the point of view of the hearer. In fact, when you play a certain pitch on any instrument, you also excite a whole series of so-called "overtones" at the same time, which are frequency multiples of 2, 4, 8 etc above the fundamental. 

You also get a sort of resonance at the fifth of the scale. It sounds, well, harmonious. Whereas if you play 2 pitches that are only a tone, or semitone, apart, you get no resonance but a harsh sounding beat frequency as the two pitches go in and out of phase with one another.

So I do not think it is just a matter of convention. Doubling the frequency has a physical significance that the ear recognises.     

Posted
19 minutes ago, altaylar2000 said:

What I mean. Let's forget about the question of whether light is particles, we will just talk about light, abstracting from what it is.

If I see a green table, it's because it reflects the green part of the spectrum, roughly speaking. So when I see objects I only see reflected light

If you see an orange-red neon sign, you are seeing photons directly from the source.

Posted
3 minutes ago, exchemist said:

Surely the point about octaves is that if you double the frequency you get something that resonates with the fundamental. And if you double it again, the same occurs. So doubling has a real significance, both from the point of view of physics and from the point of view of the hearer. In fact, when you play a certain pitch on any instrument, you also excite a whole series of so-called "overtones" at the same time, which are frequency multiples of 2, 4, 8 etc above the fundamental. 

You also get a sort of resonance at the fifth of the scale. It sounds, well, harmonious. Whereas if you play 2 pitches that are only a tone, or semitone, apart, you get no resonance but a harsh sounding beat frequency as the two pitches go in and out of phase with one another.

So I do not think it is just a matter of convention. Doubling the frequency has a physical significance that the ear recognises.  

 

Thanks, this is the first answer on the merits of the question

2 minutes ago, swansont said:

If you see an orange-red neon sign, you are seeing photons directly from the source.

This has already been discussed. If this were so, we would see the light directly in front of us, that is, we would not see anything other than a white background. I believe that the light source reflects reflected light, so we see it.

Posted
27 minutes ago, altaylar2000 said:

What You described is exactly Newton's theory of vision

Which has nothing to do with anatomy 

Posted

The octaves are important- as Exchemist has explained. If two notes are in harmony then the octaves above them will also be in harmony.
The division of the octave into 5, 8 or 12  (or more) is arbitrary and largely cultural.
 

Having said that, there does seem to be something about the pentatonic scale that people all seem to "get".
 

 

Posted
4 minutes ago, altaylar2000 said:

This has already been discussed. If this were so, we would see the light directly in front of us, that is, we would not see anything other than a white background. I believe that the light source reflects reflected light, so we see it.

Oh, come on. Don’t be obtuse.

Nobody has claimed all light comes from direct sources, or all light comes from reflection. 

You can see a direct source in an otherwise dark room.

Posted
33 minutes ago, altaylar2000 said:

this is just reflection from dust and so on

No dust (or “and so on”) in a vacuum system. 

Posted
31 minutes ago, John Cuthber said:

The octaves are important- as Exchemist has explained. If two notes are in harmony then the octaves above them will also be in harmony.
The division of the octave into 5, 8 or 12  (or more) is arbitrary and largely cultural.
 

Having said that, there does seem to be something about the pentatonic scale that people all seem to "get".
 

 

I don't think the intervals of the octave are arbitrary, actually. If you take a fundamental and consider its harmonics (say a vibrating string with one, two, three, four  etc standing waves),  you start to get the other intervals that make up the musical scale. For example a C fundamental will have a 1st harmonic of C at the octave above, but the 3rd harmonic will be G at the octave plus a fifth above, the 4th will again be C but 2 octaves up, and the 5th harmonic will be E, a major third up from that (I think: it is hard to remember exactly how it works).  

So it is not coincidence that the major triad in harmony has the tonic, fifth and major third in it. These pitches are all part of the same family of overtones, from an implied   lower fundamental. From what I recall, most of the notes of the Pythagorean scale were derived in this sort of way.

The pentatonic scale, I think, still has the intervals of the third and the fifth in it, so is not inconsistent with the same physical principles - unsurprisingly.

 

   

Posted
54 minutes ago, altaylar2000 said:

No, it doesn't mean. It has nothing to do with it

Can you elaborate?

 

Regarding the original question; I did a quick search and I am unable to find consensus. Some papers argue that musical ratios such as octaves are connected to physical properties of the human ear, example:  

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0037988

Quote

Since the receptors of the inner ear – the outer hair cells – get feedback from the central nervous system, neural influences might also contribute to cochlear tuning. Whether or not this is the case, the attractive feature of the standing wave model is that it points to musical ratios arising directly from anatomically defined inter-cell lengths, a notion not far from the original plucked string idea formulated by Pythagoras. We are led to conjecture that our perception of music is connected with anatomical and mechanical properties of the inner ear, an organ which appears to operate as a very subtle, highly tuned active acoustic resonator. The Pythagorean statement connecting music with geometry might have real physical meaning, since the results presented here raise the possibility that music might have its roots within the structure of the human ear.

But other papers argue that perceptions of musical octaves are learned:

https://www.quantamagazine.org/perceptions-of-musical-octaves-are-learned-not-wired-in-the-brain-20191030/

Quote

Musical pitch perception is argued to result from nonmusical biological constraints and thus to have similar characteristics across cultures, but its universality remains unclear. We probed pitch representations in residents of the Bolivian Amazon—the Tsimane', who live in relative isolation from Western culture—as well as US musicians and non-musicians. Participants sang back tone sequences presented in different frequency ranges. Sung responses of Amazonian and US participants approximately replicated heard intervals on a logarithmic scale, even for tones outside the singing range. Moreover, Amazonian and US reproductions both deteriorated for high-frequency tones even though they were fully audible. But whereas US participants tended to reproduce notes an integer number of octaves above or below the heard tones, Amazonians did not, ignoring the note “chroma” (C, D, etc.). 

Link to paper: https://www.cell.com/current-biology/fulltext/S0960-9822(19)31036-X

 

Posted
21 minutes ago, Ghideon said:

Can you elaborate?

I don't know where space and mirror have to do with it. Light is reflected by all objects, no mirror is needed, and it spreads in space, space has nothing to do with it

 

Posted
6 minutes ago, altaylar2000 said:

I don't know where space and mirror have to do with it. Light is reflected by all objects, no mirror is needed, and it spreads in space, space has nothing to do with it

I tried to to draw logic conclusions from your descriptions. Let's try this instead: Please describe your personal model of light. What does your model predict better or different than the currently established theories?

Posted
25 minutes ago, Ghideon said:

I tried to to draw logic conclusions from your descriptions. Let's try this instead: Please describe your personal model of light. What does your model predict better or different than the currently established theories?

There are two models of light: wave and particle, there is a hybrid.
But this is invariant to the issue under discussion. I have no personal "constructions" here, what is said about absorption and reflection in any model is the same.

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