Does light really exist?

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Does light really exist?

Postby handmade on June 25th, 2017, 10:19 am 

There is no evidence the sun emits light, there is evidence that substance is needed to produce light, is the only light we see only that of point source? Do things effectively ''glow in the dark'' when there is enough magnitude of EMR present to make it ''glow in the dark''.
Without substance there is no light even when EMR is present. Evidently between the distant stars.
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Re: Does light really exist?

Postby Watson on June 25th, 2017, 12:49 pm 

Light is a form of radiation, and radiation in many wavelengths does exist.
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Re: Does light really exist?

Postby handmade on June 25th, 2017, 1:08 pm 

Watson » June 25th, 2017, 11:49 am wrote:Light is a form of radiation, and radiation in many wavelengths does exist.


As far as the human mind experiment is concerned, observable light is between the wavelengths of 400nm-700nm. Substances provide this, without substances to provide this , it would be effectively dark .


We do not observe light between bodies we only observe the bodies, the perception of daylight is that of the body.

Objectively observable light produced by the substance and radiation reaction. There is no apparent evidence of observable light passing through space?
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Re: Does light really exist?

Postby Watson on June 25th, 2017, 2:19 pm 

Is this a lecture? Don't mind if I just slip out the back.
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Re: Does light really exist?

Postby handmade on June 25th, 2017, 3:22 pm 

Watson » June 25th, 2017, 1:19 pm wrote:Is this a lecture? Don't mind if I just slip out the back.



A lecture? No , a question.

Maybe I should re-phrase the question,

Can observable light exist without a substance that creates a wave-length of 400nm-700nm?
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Re: Does light really exist?

Postby Watson on June 25th, 2017, 4:51 pm 

Yes and No.

Light radiation is created by something. Without something to create it, light doesn't exist. So No.

But light from distant sources is reaching us millions of years after it was produced by the bright object we are now seeing. That bright object may shine differently now, in that local region of the Universe, or it may have stopped shining altogether, but we see it as it was millions of years ago.
So yes, light does exist without the something that initially created it.
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Re: Does light really exist?

Postby handmade on June 25th, 2017, 8:14 pm 

Watson » June 25th, 2017, 3:51 pm wrote:Yes and No.

Light radiation is created by something. Without something to create it, light doesn't exist. So No.

But light from distant sources is reaching us millions of years after it was produced by the bright object we are now seeing. That bright object may shine differently now, in that local region of the Universe, or it may have stopped shining altogether, but we see it as it was millions of years ago.
So yes, light does exist without the something that initially created it.



A yes and no answer can only be incompleteness in the answer, an uncertainty would develop and the premise for argument would begin.



You say the light from distant sources is reaching us, except objectively the distant source is the only light we see as you have already agreed with in your first part of your reply.

In essence the distant source is illuminating in the dark, the space between observer and distance source being relative dark which is evidently provable by observation between the stars and the relative dark back ground of space.

This brings to my attention concerns for the nature of light and the question of lights existence. Observable light is quite clearly dependent to the point source we are observing. We observe no independent light in/of space itself.

I have added a diagram that shows a star and a body, darkness surrounds both bodies, but if you can imagine a glass bottle between the bodies, the nature of darkness is clear and transparent . What we call darkness is not without light, it would be darkness is without substance producing the wavelength 400nm-700nm.

glass.jpg


Now if we was to remove the body and look away from the star, we would observe the below diagram:
l1.jpg



Now what you are looking at in the above diagram is not darkness, it is ''gin'' clear, however there is no substance interacting with radiation that produces observable light and a point source.
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Re: Does light really exist?

Postby Watson on June 26th, 2017, 9:40 am 

If you are not looking at it, you do not see it. That does not mean it it is not there. HMmmmmmmmmmmmmmmmmm......................................................

Seem you want to prove the light does not exist because you do not see it, when you look away from it. Radiation does exist, and if you don't see it now, someone else will see it sometime later.
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Re: Does light really exist?

Postby BurtJordaan on June 26th, 2017, 12:47 pm 

Radiation is only detectable if it interacts with something, be it by transferring energy, momentum or curving spacetime.

So if you define "exists" as being detected, yes, then light does not 'exist' unless interacting. But then it becomes a "what does existence mean?" philosophical argument.
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Re: Does light really exist?

Postby Dave_Oblad on June 26th, 2017, 12:56 pm 

Hi Handmade,

handmade wrote:Without substance there is no light even when EMR is present.

EMR is Light. You have said: "Without a reflective substance, there is no light even when light is present".

Wiki wrote:The effects of EMR upon chemical compounds and biological organisms depend both upon the radiation's power and its frequency. EMR of visible or lower frequencies (i.e., visible light, infrared, microwaves, and radio waves) is called non-ionizing radiation, because its photons do not individually have enough energy to ionize atoms or molecules. The effects of these radiations on chemical systems and living tissue are caused primarily by heating effects from the combined energy transfer of many photons. In contrast, high ultraviolet, X-rays and gamma rays are called ionizing radiation since individual photons of such high frequency have enough energy to ionize molecules or break chemical bonds. These radiations have the ability to cause chemical reactions and damage living cells beyond that resulting from simple heating, and can be a health hazard.

https://en.wikipedia.org/wiki/Electromagnetic_radiation

It sounds like the argument is that EMR (light) is not present if a Reflective Substance isn't present to reflect it. If that is the case then please define a hard shadow.

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Dave :^)
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Re: Does light really exist?

Postby handmade on June 26th, 2017, 1:19 pm 

BurtJordaan » June 26th, 2017, 11:47 am wrote:Radiation is only detectable if it interacts with something, be it by transferring energy, momentum or curving spacetime.

So if you define "exists" as being detected, yes, then light does not 'exist' unless interacting. But then it becomes a "what does existence mean?" philosophical argument.


I do not ''see'' this to be a philosophical argument, we are discussing the physics and talking about a process that is seemingly self explanatory and self evident.

Observable light is without any doubt in my mind the process of interaction of EMR and other substance.

Observable light can not ''exist'' if there is no interaction.

I think the ''key'' to understanding this is firstly discussing ''darkness'', I do not believe there is such a thing as darkness, what we perceive as darkness is actually ''gin clear'' or transparent if you like.

I believe shining a laser in the ''dark'' at a wall shows this. We can see the laser dot on the wall where the laser is reacting with the wall. If we were to add a medium of smoke we can observe the incident ray , but we can not observe a reflecting ray.
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Re: Does light really exist?

Postby handmade on June 26th, 2017, 1:23 pm 

Dave_Oblad » June 26th, 2017, 11:56 am wrote:Hi Handmade,

handmade wrote:Without substance there is no light even when EMR is present.

EMR is Light. You have said: "Without a reflective substance, there is no light even when light is present".

Wiki wrote:The effects of EMR upon chemical compounds and biological organisms depend both upon the radiation's power and its frequency. EMR of visible or lower frequencies (i.e., visible light, infrared, microwaves, and radio waves) is called non-ionizing radiation, because its photons do not individually have enough energy to ionize atoms or molecules. The effects of these radiations on chemical systems and living tissue are caused primarily by heating effects from the combined energy transfer of many photons. In contrast, high ultraviolet, X-rays and gamma rays are called ionizing radiation since individual photons of such high frequency have enough energy to ionize molecules or break chemical bonds. These radiations have the ability to cause chemical reactions and damage living cells beyond that resulting from simple heating, and can be a health hazard.

https://en.wikipedia.org/wiki/Electromagnetic_radiation

It sounds like the argument is that EMR (light) is not present if a Reflective Substance isn't present to reflect it. If that is the case then please define a hard shadow.

Regards,
Dave :^)



EMR is the general term we use , observable light does not exist without interaction. At this time I am discussing observable light, temporal constants of EMR. EMR is always present, but EMR is not observable light.
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Re: Does light really exist?

Postby handmade on June 26th, 2017, 1:26 pm 

Watson » June 26th, 2017, 8:40 am wrote:If you are not looking at it, you do not see it. That does not mean it it is not there. HMmmmmmmmmmmmmmmmmm......................................................

Seem you want to prove the light does not exist because you do not see it, when you look away from it. Radiation does exist, and if you don't see it now, someone else will see it sometime later.



What if I told you , you could be directly looking at an object and still could not see it ?



An object receding away from an observer will incur a visual volume contraction to an eventual zero point dimension.
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Re: Does light really exist?

Postby Watson on June 26th, 2017, 1:58 pm 

BurtJordaan » Mon Jun 26, 2017 11:47 am wrote:Radiation is only detectable if it interacts with something, be it by transferring energy, momentum or curving spacetime.

So if you define "exists" as being detected, yes, then light does not 'exist' unless interacting. But then it becomes a "what does existence mean?" philosophical argument.


Good of you to join us. Admittedly I'm not sure what we are talking about here. Seems the argument is "exists defined as being detected" but that is like saying the wind doesn't exist unless it is detected against a flag or felt on your cheeks.
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Re: Does light really exist?

Postby handmade on June 26th, 2017, 2:21 pm 

Watson » June 26th, 2017, 12:58 pm wrote:
BurtJordaan » Mon Jun 26, 2017 11:47 am wrote:Radiation is only detectable if it interacts with something, be it by transferring energy, momentum or curving spacetime.

So if you define "exists" as being detected, yes, then light does not 'exist' unless interacting. But then it becomes a "what does existence mean?" philosophical argument.


Good of you to join us. Admittedly I'm not sure what we are talking about here.


Let me try to explain without using science. Look at any object in your room, the space between your eye and object is full of air, there is no observable light in this space. What colour is the object you are viewing? Could you measure the object to be in a different position relative to yourself? Could You measure the colour of the object to be in a different relative position to yourself?

Could we conclude that the only observable light we are seeing is in that position relative to yourself?
red dot.jpg


The darkness around the red dot is an ''illusion'' , the darkness is ''gin clear''.
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Re: Does light really exist?

Postby BurtJordaan on June 26th, 2017, 4:00 pm 

Frankly, I still do not know what you are saying. The area around the red dot is full of light (radiation), just not necessarily observable without suitable detectors. AFAIK, there are no places in our universe devoid of radiation.
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Re: Does light really exist?

Postby handmade on June 26th, 2017, 4:25 pm 

BurtJordaan » June 26th, 2017, 3:00 pm wrote:Frankly, I still do not know what you are saying. The area around the red dot is full of light (radiation), just not necessarily observable without suitable detectors. AFAIK, there are no places in our universe devoid of radiation.


The red dot is not surrounded by observable light, yes the red dot is surrounded by radiation, we are talking about the human mind experience, detecting devices do not come into this at this stage.
We can measure the observable light of the red dot to be in its exact position relative to us.

added- I will redefine the red dot to be a laser dot, please prove there is a reflective ray without using a mirror?

The wall is not a reflective surface than can redirect the beam like a reflective surface. The smoke medium shows evidently there is no reflective light from the wall entering your eyes.
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Re: Does light really exist?

Postby Watson on June 26th, 2017, 5:10 pm 

Well I'm frustrated by the nonsense of this, and what the hell is clear gin?

Let me try to explain without using science.

I'm pretty sure that is what you have been doing to this point.
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Re: Does light really exist?

Postby handmade on June 26th, 2017, 7:59 pm 

Watson » June 26th, 2017, 4:10 pm wrote:Well I'm frustrated by the nonsense of this, and what the hell is clear gin?

Let me try to explain without using science.

I'm pretty sure that is what you have been doing to this point.



I really have to explain to an adult what gin clear means? huh...


Have you not ever drunk water and noticed it is see through ?
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Re: Does light really exist?

Postby Watson on June 26th, 2017, 9:46 pm 

If 'clear gin' means clear? Why not just say clear? To say clear gin sort of implies you mean something other than, in addition to, or more than just clear.
Anyway I think I'll leave this to the others to sort out with you.
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Re: Does light really exist?

Postby Dave_Oblad on June 26th, 2017, 10:06 pm 

Hi handmade,

handmade wrote:The wall is not a reflective surface than can redirect the beam like a reflective surface.

A mirror can redirect light with more precision than a rough surface. If the mirror is nearly perfect (I've worked with those before with lasers) then you can not see the red spot on the mirror as 99.99% of the light is bounced at whatever mirror angle. On the other hand, light hitting a non-mirror surface will be dispersed at all possible angles, making it very visible from anywhere you have a clear view of the spot.

Within a room, light bounces all over the place and is called ambient light. I hope you understand the idea behind dispersed light? It is reflected light off all exposed surfaces at all possible angles.

Like everyone else, I don't understand what point you are trying to make. Are you trying to state that light is invisible until it hits an Object and is reflected? That seems like a rather mundane observation given light travels in a straight line until it hits something.

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Dave :^)
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Re: Does light really exist?

Postby handmade on June 26th, 2017, 10:21 pm 

Watson » June 26th, 2017, 8:46 pm wrote:If 'clear gin' means clear? Why not just say clear? To say clear gin sort of implies you mean something other than, in addition to, or more than just clear.
Anyway I think I'll leave this to the others to sort out with you.



I said ''gin'' clear , not clear gin. It is a comparison to remove ambiguity from just saying clear. Quite clearly you are just being a bit awkward.
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Re: Does light really exist?

Postby handmade on June 26th, 2017, 10:26 pm 

Dave_Oblad » June 26th, 2017, 9:06 pm wrote:Hi handmade,

handmade wrote:The wall is not a reflective surface than can redirect the beam like a reflective surface.

A mirror can redirect light with more precision than a rough surface. If the mirror is nearly perfect (I've worked with those before with lasers) then you can not see the red spot on the mirror as 99.99% of the light is bounced at whatever mirror angle. On the other hand, light hitting a non-mirror surface will be dispersed at all possible angles, making it very visible from anywhere you have a clear view of the spot.

Within a room, light bounces all over the place and is called ambient light. I hope you understand the idea behind dispersed light? It is reflected light off all exposed surfaces at all possible angles.

Like everyone else, I don't understand what point you are trying to make. Are you trying to state that light is invisible until it hits an Object and is reflected? That seems like a rather mundane observation given light travels in a straight line until it hits something.

Regards,
Dave :^)


Not quite Dave, I am trying to say that light does not exist, light does not travel through space, observable light is a product of process when EMR interacts with a substance and we observe ''light'' in it's exact geometrical relative position.

So if you are looking at something red, the red you observe is not a picture in your mind, it is the reality outside of your mind and in its exact geometrical position. I believe what we see is live , I do not see any pictures in my head, the picture I observe is outside of my head and a live feed. I do not believe or think that light needs to reflect off an object into our eyes to see that object. I do not believe light reflects off normal surfaces. The evidence suggests otherwise.

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Re: Does light really exist?

Postby BurtJordaan on June 27th, 2017, 1:01 am 

steve,
handmade » 27 Jun 2017, 04:26 wrote:I do not believe or think that light needs to reflect off an object into our eyes to see that object. I do not believe light reflects off normal surfaces. The evidence suggests otherwise.

Huh?

Steve, I think you have just contradicted yourself. It reads that the evidence contradicts what you belief. So what is the point that you are making?
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Re: Does light really exist?

Postby bangstrom on June 27th, 2017, 3:04 am 

handmade » June 26th, 2017, 9:26 pm wrote:
I do not believe or think that light needs to reflect off an object into our eyes to see that object. I do not believe light reflects off normal surfaces. The evidence suggests otherwise.


What are "normal" surfaces and what evidence?

As I understand it, your question is, Does light exist in the space between a signal and receiver? In other words, Does light travel through the space between or is light a direct exchange of energy from one object to another? Is that your question?
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Re: Does light really exist?

Postby handmade on June 27th, 2017, 3:56 am 

BurtJordaan » June 27th, 2017, 12:01 am wrote:steve,
handmade » 27 Jun 2017, 04:26 wrote:I do not believe or think that light needs to reflect off an object into our eyes to see that object. I do not believe light reflects off normal surfaces. The evidence suggests otherwise.

Huh?

Steve, I think you have just contradicted yourself. It reads that the evidence contradicts what you belief. So what is the point that you are making?



Huh? I think you have read it wrongly, ambiguity is a problem by all on science forums, we read things differently at times. I have not contradicted myself, I said the evidence suggests I am correct , not the the evidence proves me incorrect.

Regards

Steve
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Re: Does light really exist?

Postby handmade on June 27th, 2017, 4:01 am 

bangstrom » June 27th, 2017, 2:04 am wrote:
handmade » June 26th, 2017, 9:26 pm wrote:
I do not believe or think that light needs to reflect off an object into our eyes to see that object. I do not believe light reflects off normal surfaces. The evidence suggests otherwise.


What are "normal" surfaces and what evidence?

As I understand it, your question is, Does light exist in the space between a signal and receiver? In other words, Does light travel through the space between or is light a direct exchange of energy from one object to another? Is that your question?



A normal surface is a surface that does not reflect light as opposed to a reflective mirrored surface. The evidence I have already offered, it is a matter of how we interpret the evidence.

My question is does observable light exist without the interaction with a ''substance''?

My answer and previous answers in this thread say no.

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Re: Does light really exist?

Postby bangstrom on June 27th, 2017, 5:30 am 

handmade » June 26th, 2017, 12:23 pm wrote:

EMR is the general term we use , observable light does not exist without interaction. At this time I am discussing observable light, temporal constants of EMR. EMR is always present, but EMR is not observable light.

"Observable" light is a small fraction of the EMR spectrum so you can't separate the two. Light is like one note in the middle of a larger scale of notes. There is essentially nothing special about visible light that should exclude its inrteractions from consideration along with the rest of the EM scale.

You could also ask, Does EMR exist without the interaction with a ''substance''?
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Re: Does light really exist?

Postby bangstrom on June 27th, 2017, 5:53 am 

handmade » June 27th, 2017, 3:01 am wrote:
What are "normal" surfaces and what evidence?

A normal surface is a surface that does not reflect light as opposed to a reflective mirrored surface. The evidence I have already offered, it is a matter of how we interpret the evidence.

I think what you mean is a "normal" surface is one that scatters light like a wall and not one that reflects light in a single direction like a mirror. All surfaces reflect light to some degree.

handmade » June 27th, 2017, 3:01 am wrote:

My question is does observable light exist without the interaction with a ''substance''?

My answer and previous answers in this thread say no.

That helps to clarify things but I think you should include all of EMR along with your definition of "light."
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Re: Does light really exist?

Postby bangstrom on June 27th, 2017, 6:04 am 

Watson » June 25th, 2017, 3:51 pm wrote:Yes and No.

Light radiation is created by something. Without something to create it, light doesn't exist. So No.

But light from distant sources is reaching us millions of years after it was produced by the bright object we are now seeing. That bright object may shine differently now, in that local region of the Universe, or it may have stopped shining altogether, but we see it as it was millions of years ago.
So yes, light does exist without the something that initially created it.

Your statements begin and end with the assumption that that light exists between signal and sink and that our conventional theories of light are correct so you are using the theory in question to explain its correctness.

The question is, Does light exist between signal and sink or is light better understood as a potential quantized state of energy which can only be measured, or said to "exist" when it interacts with another particle? By “exist” I mean is light manifestly present in space-time or could it be that it is not light that is "moving" but only it's potential to become manifest?

Assuming that Special Relativity is correct it can be demonstrated that photons do not experience space or time due to the effects of dilation and contraction. For light, emission and absorption are simultaneous so light has neither time nor space in which to exist or propagate throughout the universe.

Can this mean that photons simply do not "exist"? What if a photon is simply a potential quantized state of energy which can only be measured, or said to "exist" when it interacts with another particle? Is the thing that is actually traveling through space-time merely the photon's calculated probability function? Is it possible that the wavelength of any given photon does not exist and can in no way be measured until it interacts with another particle?

And, is energy conserver if there are millions of years of stellar emissions drifting through space waiting to arrive? It has been said that energy has no holding pattern.
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