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User talk:Paine Ellsworth/Light's nature

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Just had a thought about light that I've never read anywhere. The vast majority of light in the Universe is actually invisible and goes unseen by all of us. Think about it. We look up at the stars and, assuming that our vision is unimpaired and not obstructed, we see pinpoints of light. Each light is a star (or planet). Each star emits light and other radiations in all directions; however, the only light we see is the light that comes directly to our eyes. That's worth a repeat: the only light we see are two little rays of light that come directly to our eyes. All the other light emitted by the stars in all other directions is invisible to us!
If I were in New York and you were in California, and we look up at the full Moon one night, we see pretty much the same Moon. It's in a different position in the sky, but it's the same moonlight, right? Wrong. The source light from the Sun takes about 8 minutes to get to the Moon, bounces off the surface of the Moon, and then takes about a second and a half to get to our eyes. The light you see is made up of different rays than the light I see. I can't see the light rays you see, and you can't see the light rays I see. Heck, if you and I were standing together in the middle of the Sahara desert looking up at the full Moon, the same would be true. If you look over at the area between me and the Moon, you cannot see the rays of light from the Moon that I see. That light is invisible to you. So the vast majority of light goes in all other directions and those light rays are invisible to us! Yo, Jimbo! Do you see the light?

A few facts: the Sun is a star, one of billions of stars in our galaxy, the Milky Way. The Sun emits light energy that drenches the Earth, your part of the Earth, everyday. The Earth makes one full turn around the Sun each year, and we know that about the same amount of light hits the Earth in the summer, the winter, in fall and in spring, which leads us to know that the Sun, and in fact all of the stars we can see, emit light in all directions.

And yet, the only light we can actually see is the light that precisely targets our eyes. You cannot see the light that targets my eyes, and I cannot see the light that targets your eyes. Neither of us can see the light that is given off by a star in all directions other than the direction that targets our eyes. It is absolutely astounding to me that the vast majority of light in the Universe is invisible to me!... to us!... to every living creature we know that has eyes to see!

To top it off

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To top things off, we must also remember what "sight" actually is. Light, in the form of photons and waves, travels from its source to our eyes, through our lenses, and is gathered by the special cells on our retinas, the rods and cones. Then the light becomes something else. It becomes impulses that travel from our eyes to our brains. In the brain those impulses are received, compared with what we already know (or don't know), and then they travel back to our eyes (all this happens very quickly, the impulses travel at about 300 feet per second) where the light is actually sensed. So what we "see" is not actually the light itself, what we see is what our brains allow us to see or make us see. What we see is whatever image our brains manufacture based upon the impulses they receive from our eyes. As an aside, this is also true of our other physical senses, taste, touch, smell, and hearing, as well.

Checker shadow illusion

In the image above, the squares marked A and B are the same shade of gray. To prove that, here is another image...

In this second image, the picture on the right has lines that show the consistency of shade between squares A and B. And yet, even fully knowing this, our minds look back at the picture on the left and see A and B as different shades of gray! Our minds refuse to accept that the two squares are exactly the same shade of gray. Is this a flaw? Are our brains flawed and incapable of rendering the truth? That is not known for certain, but the smart ones among us seem to think that it represents some sort of protection mechanism within the brain.

Here is another illusion that impresses me to no end. It's called the Flash lag illusion...

We actually see the moving spot ahead of where it really is. Our minds automatically anticipate for us. In the military we were trained not to anticipate a command, which is one of the hardest things to learn. And now I know why. This is reason not to fear ai-ai-AI. Machines will never be able to anticipate like we can, so we will be able to turn them off, unplug them, before they can hurt us. We will anticipate their every move.

Mighty Mind

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The light we see, then, is interpreted by our brains in the best manner possible to allow us to sense the outer world. It's just not always a faithful interpretation, but it's the best possible interpretation we can muster. Also, it is interesting to note again that even when we know what's right, we might still actually perceive the wrong thing or something a little different. I call that "being human".

Perception, then, is the result of the brain's interpretation of the impulses it receives from what we have sensed. Is that all? What about the lion and the antelope? From the lion's point of view (POV) the antelope would make a good meal for her and her cubs. And from the POV of the antelope, it does not intend to become anybody's meal. So perception is also the result of both the "nature of the beast" and of that beast's willingness to conform to another beast's opinion. Remember... anticipation is not just a human trait, it is an ability held by all living things and is one of the ways that life is different from non-living things.

While peripheral to all this, it is a good time to point out that this also illustrates the human challenge of discerning between good and evil. If the lion chases and catches the antelope, that is a good thing for her and her cubs, but not so good for the antelope. On the other hand, if the antelope gets away, it's good for the antelope but not so good for the lion and her cubs. They might starve to death if they don't find something to eat. The difference between good and not so good isn't always a cinch to discern. Sometimes it is a cinch, sometimes not so much. But we digress.

Perception, at least in part, is the result of the brain's interpretation of the impulses it receives from what has been sensed. Our eyes sense light, which transforms into impulses that our brains receive. We look at a star and we sense a pinpoint of light in the sky. Beyond that, we only know what science has revealed to us. The star is generally a huge sphere of hot gas and plasma, but it's so far away that we can only discern a pinpoint of light. Our Sun is an exception to this, because it is a star that is close enough to us to be more than just a pinpoint of light. The other exception is Betelgeuse, a star which appears as a small red disk in a powerful telescope. Our Sun appears to us as a disc of very bright light in the sky. It is so bright that it would harm our eyes to look at it for more than a fraction of a second.

Would like to give you something to take home with you, something you might cherish. If you're already home, then would like to give you something that hits home with you. It might sound maudlin, but the only thing I can think of is a kind of Love. Not the sort of love you give somebody, not the kind of love somebody gives you, but would like you to feel my deeply felt love for this world, this planet Earth where we live and thrive. That is the only thing I can think of that is worth the time and trouble you take to read this. You are a big part of this world, so thank you beyond words for reading, and for accepting this love!


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