"The Nature of Objective Reality" .... (according to me, obviously)

[CapelDodger]

Personally, I find the entire 'is your blue my blue' discussion pointless and silly.

Solipsism. 'Nuff said.

One guy's attitude towards a guy that's had his (the first guy's) sister can be compared to some other guy's yadda yadda ... Solipsism is a sorry alternative to the soap-opera going on all around us.

Blue is what the bluebells in my garden look like, and everybody thinks they're pretty.

 

[Gnu Ordure]

whoops, sorry, I just noticed I forgot to include a link in one of my earlier posts... when I said to ichneumonwasp :

Maybe you could read that one post, and confirm (or not) that I've understood you correctly ?

(And for those of you for whom life is also too short to read the whole 4 pages, this single short post happens to summarize my starting-point concisely).

sorry, I meant to include this :

http://www.internationalskeptics.co...p=2526007&highlight=ichneumonwasp#post2526007

And I'd like you to know that the sub-editor responsible for this lapse has already been identified, charged, tried, and found guilty, and will never work in this town again.

It's the least I could do....



Gnu..

 

[Gnu Ordure]

Once again you make an error. The wave/particle duality of light is not what light is.

I didn't say it was, qayak. Wave/particle duality is an idea about the properties of light, it's not light itself, agreed.

(wiki: "In physics and chemistry, wave-particle duality is a conceptualization that all objects in our universe exhibit properties of both waves and of particles")

Which is why I'm saying that it's incorrect to describe 'blue light' as being a wave of a particular length.

It might just as accurately be described as being a stream of particles.



Whether to perceive light as being either wave or particle depends on the decision of the observer.



Therefore, waves or particles can't be part of the objective definition.





As you say, qayak :

"wave/particle duality of light is not what light is".

So tell me (since you seem to know) ...


... without reference to waves or particles ...


.... what is light, exactly ?



Gnu.

 

[Slimething]

.... what is light, exactly ?

Balsa wood, styrofoam, cork, feathers, dust bunnies, ... That's the best I can do to define light without refering to waves or particles.

 

[qayak]

Whether to perceive light as being either wave or particle depends on the decision of the observer.

Actually it probably depends more on the problem the observer is trying to deal with. Whichever model works better is the one they will use.

Therefore, waves or particles can't be part of the objective definition.

Each observer will see the same thing. The phenomenon is independent of the observer so it is objective. You are getting the model of light mixed up with light itself. You assume that how different observers interpret the information has an affect on the event itself. You and I both observe Young's double slit experiment. You interpret it using the particle theory and I interpret it using the wave theory. It is irrelelvent to the experiment. We both observed the same thing but we are using two different theories to explain it.

As you say, qayak :

"wave/particle duality of light is not what light is".

So tell me (since you seem to know) ...


... without reference to waves or particles ...


.... what is light, exactly ?

A lot better minds than mine have failed at this one. If you were reading the other thread where someone linked Richard Dawkins' talk on somethings in science being "stranger than we can imagine," this is one of those things. We use the wave/particle duality to describe light because we understand waves and particles and they have some features in common with light. However, neither describes all we observe about light so we know neither is correct. Light must be something different yet, but what? Is it too strange for us to even imagine?



Gnu.[/QUOTE]

 

[qayak]

Which is why I'm saying that it's incorrect to describe 'blue light' as being a wave of a particular length.

It might just as accurately be described as being a stream of particles.

It is not incorrect to describe blue light as being light with a certain wavelength, that is a fact. The stream of particles desription does not explain why the light is blue, the wave description does. That is the reason for the two models, each has advantages depending on the circumstance.

 

[drkitten]

Could you lob a citation this direction? This is an area of much interest for me, and I am unaware of this finding.

I couldn't find the direct citation, but here's a way someone managed to do it via (abnormal) retinal stimulation.

Isn't science cool?

 

[Molinaro]

Mental masturbation. All of it. I can't imagine the blisters you must have after such a marathon of verbal wanking.

I'm not even sure where to begin with such silliness. A wavelength is 'objective', as it exists independently of my interpretation of it. A colour is a description of that wavelength. Indeed, there are issues that are raised when we introduce variation in retinal sensitivity and colour blindness, but if you show a chart and say 'this is the colour blue', that same perceived colour will remain defined as blue for all every time I see that wavelength. Hence you won't get '95.6%' or whatever nonsense number you pulled out of nowhere, but you'd get everybody agreeing that that was blue.

(ETA: colour blindness resulting from a reduction in the types of retinal cells means we will confuse wavelengths of light with one another. This is not a subjectivity of the wavelength, but rather a processing problem of light wavelengths. Therefore there are subjective perceptions of colour patterning, but the colour itself as a stimulus is objective enough).

Subjective experience would create disagreement, where my cut off for what I term 'blue' is different to yours, but that's a matter of semantics and not of subjectivity of the nature of colour.

Hell, if you want to define colour as the perception resulting after the photon hits the eye, be my guest. Who cares?

Man, why did I just enter this loony discussion?

Athon

Actualy that is 100% wrong. You can verify it with the following experiment:

Part 1

- In a dark room have 3 spot lights, 1 red, 1 green and 1 blue.
- On a black wall place a 1 foot square colored blue.
- Set the 3 lights to equal intensity and shine them on the square, and you will see it as a blue square.
- Use a photometer to measure the light reflected off the blue square and you will see that it agrees with your assertion that the wavelength of the reflected light is in fact blue.


Part 2

- Vary the intensity of the 3 spot lights until the square no longer looks blue.
- The photometer will agree that the wavelength of the reflected light is no longer blue.

Part 3 (the interesting part!)

- Instead of having just the 1 blue square on the wall, surround it with other squares of the same size, that are different colors, such as yellow, green, red, etc...
- Vary the lights so that the photometer registers something other than blue reflecting off the blue square and low and behold .. it still looks blue!

The absolute wavelength of the light reflecting off an object does not determine the colour you see. Your interpretation of the colour of an object is actualy dependant on the colour of adjacent objects, moreso than the absolute wavelenght of the light reflecting off of it.




And, on another note. I don't see your objection at the end of your post as being what is in question. I may call all blue objects blue, just like someone else will always call those objects blue. However, the experience of seeing blue in my mind may well be indentical to what your mind experiences when seeing yellow. There is no way of knowing if our experiences of a particular colour are the same as someone else's experiences.

 

[Gnu Ordure]

Balsa wood, styrofoam, cork, feathers, dust bunnies, ... That's the best I can do to define light without refering to waves or particles.

Indeed, slimething.

And we're agreed, I hope, that naming the end-result of our vision process (this cork, that feather), does not help us to define the nature of light.

And as qayak says, using waves or particles is inadequate:

However, neither describes all we observe about light so we know neither is correct. Light must be something different yet, but what?

(I don't know, qayak. I was hoping you could tell me....)



We are trying to agree on an absolutely certain objective ("irrespective of observer") definition of 'blue light'.

Molinaro, thank you for contribution, but I'm not sure that it's necessary; I said yesterday :

One thought, though. I'm not trying to state beyond all doubt that all people with normal vision have a standard response to a particular stimulus, so I think that part of the discussion is a bit of a red herring.

Or a reddish herring, anyway.

The point, whatever we each see in response to "light with a wave-length of 465 mn", we see something.. We each have an experience of "465mn-ness".

And for this experience (vision) to happen, it is absloutely necessary for light to enter an eye and then be transformed by the brain into vision.

This experience simply cannot happen without eyes. Without observers.

So the concept of vision (which includes colour) cannot be any part of an objective definition of light, because light is invisible until it enters an eye.


Exactly the same as the tree falling in the forest. When it hits the ground, it creates mechanical vibrations in a medium which emanate from this source. An objective definition of this phenomenom is only concerned with these vibrations, including how they travel and how they interact and bounce off any objects (any object except an ear, that is).

In the absense of observers (no ears+brain), the objective definition of the sound-wave cannot include speculation as to how these vibrations might be experienced, after entering an ear, as hearing.

So, without ears, the forest is silent.


Vibrations (sound-waves) are inaudible until they enter an ear.

Light is invisible until it enters an eye.





Hmm, I'm not sure where this argument is going...

... pause for feedback indicated ...



Light is invisible until it enters an eye.

Is that correct ? Or not ?


Gnu.



PS Editplus - Maybe a better way to put it would be :

"Objects are invisible until light bounces off them into an eye".


That seems to make more sense, doesn't it ? The principle's the same.

 

[Molinaro]

The main point of my post is that what people were saying was wrong. Just because light of 465nm enters my eye and yours does not mean we see the same colour. You have to also consider what else is being seen, at the same time.

 

[Gnu Ordure]

qayak, I don't get it...

first you say:

However, neither (wave nor particle) describes all we observe about light so we know neither is correct.

I agree.

But 20 minutes later, in your next sentence almost, you said :

It is not incorrect to describe blue light as being light with a certain wavelength, that is a fact.

First incorrect, then correct...

I guess what you mean is that the second definition is true only in certain circumstances.

If so, fine, I agree.

But that disqualifies it as an objective definition.

 

[Dancing David]

I didn't say it was, qayak. Wave/particle duality is an idea about the properties of light, it's not light itself, agreed.

(wiki: "In physics and chemistry, wave-particle duality is a conceptualization that all objects in our universe exhibit properties of both waves and of particles")

Which is why I'm saying that it's incorrect to describe 'blue light' as being a wave of a particular length.

It might just as accurately be described as being a stream of particles.

Whoops that is a semantic argument.

The partcicle exhibit a feature reffered to as wavelenth irregardless. the wave partcile duality is a false duality, partciles are waves all the time.

Light appears to exist, it also appears to have a wavelenth by objective standards, it also appears as a smallish particle that is bounded by the Heisenberg Indeterminancy Priciple.

If the consensus of the population is to call a particular wavelenth 'blue' or 'azul', then it is by consesus of the self referencing set of symbols.

However Merc made a very good point. Pure blue may not exist in that there may not be a wavelenth universaly called blue (if I did not misunderstand).

Whether to perceive light as being either wave or particle depends on the decision of the observer.
{/quote]
Arbitary thought construct jammed onto light, it is both a wave form and comes in discrete packets.

Therefore, waves or particles can't be part of the objective definition.

If siotropy applies and all observers report the same findings than it is objective. it is both all the time.

As you say, qayak :

"wave/particle duality of light is not what light is".

So tell me (since you seem to know) ...


... without reference to waves or particles ...


.... what is light, exactly ?



Gnu.

Silly question, silly point, light is both objectively you can measure both quantities or qualities regardless of who the observer/ measurer is.

 

[Dancing David]

qayak, I don't get it...

first you say:



I agree.

But 20 minutes later, in your next sentence almost, you said :



First incorrect, then correct...

I guess what you mean is that the second definition is true only in certain circumstances.

If so, fine, I agree.

But that disqualifies it as an objective definition.

Perhaps you need to stop and think, and read what Merc wrote?

You also need to reread what qayak wrote. Something may not describe all of a thing but describe part of it.

 

[drkitten]

PS Editplus - Maybe a better way to put it would be :

"Objects are invisible until light bounces off them into an eye".

Only in a world without photographs.

That seems to make more sense, doesn't it ? The principle's the same.

Perhaps. It clarifies what you're saying, but it also illustrates a substantial problem.

I can take a picture of an object without my seeing it. Indeed, I've rigged security cameras and such several times. The object interacts with the light, which in turn interacts with the camera. Later, if there is a need, I can pull the videotape and look at the image -- but if the night has been quiet, I will just re-tape over the old image without ever looking at it.

I don't think that you can claim that the image on the videotape is in any way subjective. I don't think you can claim that the object whose photograph I've captured via remote control is in any way subjective. The reality underlying the image is entirely objective -- only my personal experience of the picture is in any way subjective. And the camera clearly serves to separate the objective nature of the object from the subjective nature of my viewing, since I never actually view the object, but only its photograph.

And again, we're in a position where we can divide the world (in this case, very cleanly) into "subjective" and "objective" -- and once again, there's no room for "consensus." The image on the tape is objective, and my experience of what I saw on it is subjective, even if seven or eight or a thousand other people watched that tape at some point.

Otherwise, there's the following problem:

I make the tape on Sunday.
On Monday, I watch the tape and obtain a "subjective" experience of its contents.
On Tuesday, someone else watches the same and obtains their view of its contents. I hold that these are both subjective experiences -- you hold that somehow, the second viewing shifts the reality of the subjective impression into "consensus reality."

But how does someone else's experience on Tuesday, an experience that I not only do not share, but may not even be aware of -- it might be separated from me by a distance of several thousand miles! -- how does this other person's experience change mine??

 

[Gnu Ordure]

If siotropy applies....

if what ?



... I told you I was out of my depth...


I'll go and look it up, David, and I'll get back to you if I can make sense of what you're saying.

what is light, exactly ?

Silly question...

I don't see why, David.

Physicists and philosophers have been addressing this exact question for centuries - and we don't seem to have found a certain answer yet... so why do you say it's a silly question ?

As gayak says

A lot better minds than mine have failed at this one.

you then say :

light is both, objectively you can measure both quantities or qualities regardless of who the observer/ measurer is.

... but not at the same time, David, isn't that the point ?

At any moment, you have to choose; one or the other.

And surely, then you also have to specify where the observer is in relation to what is being measured, and particularly how fast the observer is moving.

Because that effects the length of object being measured.

Which in this case, is the length of a light-wave.

Hence the Doppler effect and red-shift, right ?




So the wave-nature of light (or the particle nature) is dependant on the circumstances of the observer.

But I'm interested in the objective nature of light (what it is, irrespective of observers). So models of waves or particles are inadequate.




In other words...



My question is : What was the nature of the universe 4 billion years ago ?

Before life. Before sense-organs.

(I'm assuming no extra-terrestial life exists - if it does, go back another 2 billlion years to before that life evolved).





What did the universe look like 4 billion years ago ?




Now, that's a silly question, David.

At that time, there were no eyes, so the universe couldn't look like anything.

How could it ?

Before the advent of life, the universe was completely dark, (or invisible), inaudible, unsmellable, untasteable, and untouchable.

And so on, for whatever different sense-impressions different life-forms might eventually evolve....

Because all those qualities are a function of life.

And 4 billion years ago, there was no life.



Genesis, Chapter 1, verses 1 and 2 :

"In the beginning, God created the heaven and the earth".

"And the earth was without form, and void; and darkness was upon the face of the deep".



Since I'm not a Christian, I would re-state the first verse as :

"In the beginning, the heaven and the earth started in a Big Bang".

Otherwise, it fits what I'm saying. From the creation of the universe 13 billion years ago until the development of life on this planet 3.5 billion years ago, the universe ("the earth") was 'without form'.


So, describing light 4 billion years ago using models such as wave or particle, or invoking concepts such as 'vision', is invalid, because it assumes observers who can perceive light as waves or particles, and who can experience 'vision'.

In fact, there were no observers at that time.

So what was the nature of light, at that time ?


Gnu.

 

[Wat Tyler]

So, describing light 4 billion years ago using models such as wave or particle, or invoking concepts such as 'vision', is invalid, because it assumes observers who can perceive light as waves or particles, and who can experience 'vision'.

In fact, there were no observers at that time.

So what was the nature of light, at that time ?

Gnu.

The presence (or, indeed, the absence) of 'intelligent' observers possessing eyes and brains to perceive the presence of light has no actual bearing on its objective reality/existence/nature - the presence (or otherwise) of observers only has bearing upon the said observers' subjective perceptions of the phenomenon under discussion.

As others have noted, each of us perceives reality in an entirely subjective manner, and it is not possible to objectively determine whether or not your brain perceives the 'colour' that we have all agreed to call 'blue' in exactly the same way that mine does.

One could take the fact that people have different 'favourite' colours to indicate that we perceive these 'colours' differently, and that e.g. the way in which your sensory apparatus represents the colour that we all call 'yellow' to your mind is, in fact, identical to the way in which my sensory apparatus represents the colour that we all call 'red' to my mind.

But, as noted before, there is absolutely no way of determining whether or not this is the case.

The only way that 'consensus reality' exists is that we all learn to apply the same labels to the same objects/experiences - e.g. 'cat' 'cold', 'blue', etc.

No-one can ever directly experience either anyone else's subjective experience of 'reality', or indeed 'objective reality' itself - all of our perceptions are entirely subjective, and governed by our genetic, cultural, and experiential heritages.

With my apologies to Mr. Donne, each of us is (in terms of perception and experience) an island, unless one is a solipsist, in which case everything and everyone else is merely a figment of his/her fervid mind.

 

[Gnu Ordure]

The presence (or, indeed, the absence) of 'intelligent' observers possessing eyes and brains to perceive the presence of light has no actual bearing on its objective reality/existence/nature - the presence (or otherwise) of observers only has bearing upon the said observers' subjective perceptions of the phenomenon under discussion.

I agree entirely, wat.

And my question remains... in the absense of such observers, what can truthfully be said about the "objective reality/existence/nature" of light ?


All we seem to have is that 'light' is 'electro-magnetic radiation of a certain kind'.


ie a synonym.


Gnu.

 

[Gnu Ordure]

If siotropy applies

sorry, David, I did go and look...

but 'siotropy' means nothing to wiki, and googling it produces a mere 7 hits, none of which clarifies it..

you're going to have to explain what you mean in other terms, I think....

(Edit +

...hang on, I just realized you might have made a typo, and googled 'isotropy' - that seems pertinent... is that what you meant ? I still need to go and read about it though...)

 

[Gnu Ordure]

drK,

I'm not sure what you're trying to say by introducing recording equipment into the equation.

I don't think that you can claim that the image on the videotape is in any way subjective. I don't think you can claim that the object whose photograph I've captured via remote control is in any way subjective

Yes, I can.

The photograph of the reality will be perceived according to the kind of sense-organ that perceives it, just as the reality itself would...

If the sense-organ belongs to another person with normal human vision. it will perceived as you and I see it.

If it belongs to a person with red-green blindness, it will be perceived differently.

If the sense-organ belongs to a dog, it will be perceived in black and white, with some yellow-red diffentiation.

If it belongs to a honey-bee, the compound nature of the eye plus a different colour-vision system produces a very different experience.

The experience of light (or a photograph) depends on the nature of the organ that perceives it.

I call that 'subjective'...




Whereas I'm interested in light prior to perception...


.

 

[drkitten]

Exactly my point.

The photograph of the reality will be perceived according to the kind of sense-organ that perceives it, just as the reality itself would...

[...]


The experience of light (or a photograph) depends on the nature of the organ that perceives it.

I call that 'subjective'...

As well you should. Because the experience of the photograph is indeed subjective, as any experience is.

But the photograph itself is objecive.

The experience of the photograph is not the photograph, any more than a picture of food is the food itself.


The photograph is entirely objective, as is the object photographed, and as is the light that went into making the photogtaph. There is no possibility of subjectivity, since there's no subject to do the observing and experiencing.