Is darkness a non-physical property?

[Pinball1970]

I would say it is not a physical thing to be sure. But it is an example of something non-physical nonetheless. Too bad science doesn't study non-physical things. It might learn something.

Depends what you mean by physical, is the wave function physical?

 

[Magical Realist]

I would say physical is anything that we can measure. So yes...a wave function might be physical.

Quantum Theory's 'Wavefunction' Found to Be Real Physical Entity

The wavefunction is a real physical object after all, say researchers.

www.scientificamerican.com

 

[Pinball1970]

I would say physical is anything that we can measure. So yes...a wave function might be physical.

Quantum Theory's 'Wavefunction' Found to Be Real Physical Entity

The wavefunction is a real physical object after all, say researchers.

www.scientificamerican.com

Or an abstract representation of something physical.

How about Dark Matter? Supersymmetric particles? Gravity waves? Black holes? Population 3 stars? Neutrinos?

 

[Magical Realist]

Or an abstract representation of something physical.

How about Dark Matter? Supersymmetric particles? Gravity waves? Black holes? Population 3 stars? Neutrinos?

Some of those can be measured and so are physical. Others are theoretical and so not physical at all.

 

[(Q)]

I would say it is not a physical thing to be sure. But it is an example of something non-physical nonetheless. Too bad science doesn't study non-physical things. It might learn something.

Perhaps, it's the fact that the non-physical and the non-existent are the same thing.

 

[Magical Realist]

Thoughts and ideas are real but not physical. The laws of physics are real but not physical. Many properties and qualia are too.

 

[(Q)]

Thoughts and ideas are real but not physical. The laws of physics are real but not physical. Many properties and qualia are too.

Thoughts and ideas are the physical manifestations of the neurons in the brain.

 

[Gawdzilla Sama]

Please, oh please, define "non-physical" without involving Space Ghost.

 

[Gawdzilla Sama]

Thoughts and ideas are real but not physical. The laws of physics are real but not physical. Many properties and qualia are too.

Thoughts and ideas are the result of eating tacos. There are a few more steps until we get to the brain.

 

[Pinball1970]

Some of those can be measured and so are physical. Others are theoretical and so not physical at all.

Yes and some may not be real but all have been or are studied as was the aether.
My point is that scientists explore, the physical directly, indirectly, the non physical and non existent, until being ruled out.

I think Dark matter has a few more hands to play yet but that could be a casualty in the next couple of years.

 

[James R]

If it isn't and it's physical, then what's it made of?

Darkness, being an absence of light, is not a "physical thing". It's not a thing at all. It indicates the absence of a thing.

The absence of a thing isn't "made of" anything.

Can it be measured?

Light levels can be measured. If the light level is zero (or low enough), we say it is dark.

Does it occupy space?

The absence of a thing does not occupy space.

What is its velocity?

The absence of a thing has no velocity.

CAN we see darkness?

We can see light. We cannot see the absence of light. We do, however, notice when light is absent (or very dim). In such circumstances, we often say it is dark.

How can a shadow carry information about its object?

It can't. On the other hand, the outline of the shadow - made by light - can.

Bonus question: Is a mirror in a totally dark room reflecting the darkness in front of it or is it showing the darkness inside of it?

The absence of a thing cannot be reflected. The absence of a thing cannot be made visible ("shown").

Follow up question: Is cold a non-physical property?

Cold is usually associated with an absence of warmth.

I don't know what you mean by a "non-physical property". How do you define "physical property" and "non-physical property"? Examples?

An interesting quality of darkness is that it is scale invariant.

The absence of a thing does not have qualities.

IOW, no matter how big you go, to the darkness between stars, or how small you go, to the darkness between photons, the darkness remains the same.

The absence of light remains the same.

This makes it similar to the vacuum, which is also scale invariant.

A vacuum is (typically) an absence (or near absence) of matter.

The absence of a thing has no scale, because it has no properties at all.

Or a fractal..

The vacuum is not a fractal. Nor is darkness. Try googling "fractal".

Up or down. Inside or out. Nothing changes about darkness because there is nothing there to change.

Exactly. The only thing that can be changed about the absence of a thing is to provide the missing thing.

I would say it is not a physical thing to be sure.

If you say so. What's a "physical thing"?

But it is an example of something non-physical nonetheless.

What's a "non-physical thing"? Examples?

Too bad science doesn't study non-physical things. It might learn something.

Maybe. What's a "non-physical thing"? Examples?

 

[Magical Realist]

Darkness, being an absence of light, is not a "physical thing". It's not a thing at all. It indicates the absence of a thing.

The absence of a thing isn't "made of" anything

And yet, because it is the absence of a particular kind of physical thing, it has distinctive qualities we can identify it by. Darkness then as the absence of light is qualitatively different from the vacuum which is the absence of all matter. And both of these are different from absolute zero which is the absence of heat. Not all absences are created equal it seems.

Exactly. The only thing that can be changed about the absence of a thing is to provide the missing thing.

If darkness can be made to disappear with light or reappear with the removal of light, then it must be a real property since it is being caused by a real thing. Yet it is not a physical thing at all since it defines by contrast the very physicality of light. Hence it is a real but non-physical property, just like mind is to matter.

If you say so. What's a "physical thing"?

Anything that can be present in spacetime and/or can be measured.

Maybe. What's a "non-physical thing"? Examples?

Anything not present in spacetime and/or immeasurable. Examples: consciousness, qualia like redness or sweetness or pain, ideas like democracy or quantum theory, properties like darkness, laws of physics, mathematical entities, moral values like truth, aesthetic values like beauty, the future and the past...

 

[TheVat]

I would say physical is anything that we can measure.

You mean like that 5/8 ghost you were showing us a picture of in the other thread?

 

[Magical Realist]

An interesting effect you can observe is if you shine a colored light on an object and project its shadow on a white surface. The color of that shadow will be the complimentary color of the color of the light. Red light for instance produces green shadows. But a shadow is still just darkness, the absence of the red light in this case. So the green color isn't physically "there" like the red light is. It isn't being generated by the wavelength of any light. But we see it anyway. A case of a perceived color being totally generated by the brain.

 

[Gawdzilla Sama]

Darkness is like a vacuum, there's no there there. Still straining at gnats and swallowing camels, aren't you.

 

[gmilam]

An interesting effect you can observe is if you shine a colored light on an object and project its shadow on a white surface. The color of that shadow will be the complimentary color of the color of the light. Red light for instance produces green shadows. But a shadow is still just darkness, the absence of the red light in this case. So the green color isn't physically "there" like the red light is. It isn't being generated by the wavelength of any light. But we see it anyway. A case of a perceived color being totally generated by the brain.

My cousin is color blind. Brown and green look similar to him. I wonder what color he sees in the red light's shadow.

 

[Gawdzilla Sama]

https://dj3im2gm3txew.cloudfront.net/pub/media/wysiwyg/image-folder/glasses/eye/color-blindness-types/_03_Deuteranomaly_900x600.jpg

 

[exchemist]

Darkness, being an absence of light, is not a "physical thing". It's not a thing at all. It indicates the absence of a thing.

The absence of a thing isn't "made of" anything.

Light levels can be measured. If the light level is zero (or low enough), we say it is dark.

The absence of a thing does not occupy space.

The absence of a thing has no velocity.

We can see light. We cannot see the absence of light. We do, however, notice when light is absent (or very dim). In such circumstances, we often say it is dark.

It can't. On the other hand, the outline of the shadow - made by light - can.

The absence of a thing cannot be reflected. The absence of a thing cannot be made visible ("shown").

Cold is usually associated with an absence of warmth.

I don't know what you mean by a "non-physical property". How do you define "physical property" and "non-physical property"? Examples?

The absence of a thing does not have qualities.

The absence of light remains the same.

A vacuum is (typically) an absence (or near absence) of matter.

The absence of a thing has no scale, because it has no properties at all.

The vacuum is not a fractal. Nor is darkness. Try googling "fractal".

Exactly. The only thing that can be changed about the absence of a thing is to provide the missing thing.

If you say so. What's a "physical thing"?

What's a "non-physical thing"? Examples?

Maybe. What's a "non-physical thing"? Examples?

James, in fairness, I don’t think your response here covers my counterexample of electron holes, in solid state physics. Those are mere absences, but are modelled as if they are real entities with specific properties, are they not?

 

[Gawdzilla Sama]

Still in the theory stage, yes?