Darkness does not exist by itself as a unique physical entity, but is simply the absence of light. Everything in the knowable universe is light, you yourself are made of light. The visible light spectrum is the segment of the electromagnetic spectrum that the human eye can view. More simply, this range of wavelengths is called visible light. Typically, the human eye can detect wavelengths from 380 to 700 nanometers. We are made of light but our own light is invisible to our human eyes. Human emit infrared light which we cannot see with our own eyes, so we use instruments that can detect infrared light that can see those light waves. Could you imagine if we could visibly see our own light that we emitted, we would never be able to sleep. Every time we closed our eyes, we would just see our own light, we would be driven to insanity and would die out as a species very quickly.
It turns out that roughly 68% of the universe is dark energy. Dark matter makes up about 27%. The rest - everything on Earth, everything ever observed with all of our instruments, all normal matter - adds up to less than 5% of the universe. Dark matter and dark energy aren't darkness, they are called that simply because we have no way (yet) of detecting what that dark matter/energy is. It is not dark, our human senses can't perceive it and we have no instruments as of yet to detect it. Dark matter / energy is the absence of whatever is there that we can't detect.
How dark does space get? If you get away from city lights and look up, the sky between the stars appears very dark indeed. Above the Earth’s atmosphere, outer space dims even further, fading to an inky pitch-black. And yet even there, space isn’t absolutely black. The universe has a suffused feeble glimmer from innumerable distant stars and galaxies.
Scientists Discover Outer Space Isn't Pitch-Black After All.
We quickly covered light in the physical universe and how darkness in just the absence of light, which is impossible since light is everywhere. We will now explore the darkness within, the darkness of the mind.
Complementary to Jung's idea of the persona, which is “what oneself as well as others thinks one is” [CW9 para 221], the “shadow is that hidden, repressed, for the most part inferior and guilt-laden personality whose ultimate ramifications reach back into the realm of our animal ancestors…
Our persona/character/identity is who we think we are, it is our costume for the world. Our shadow is simply the things we hide from ourselves. They appear to be in the dark shadows of our mind because we refuse to look upon them. When we do shadow work and look at the dark places in our mind, we see there never was any darkness or shadows. We have shadows because we lie to ourselves. When you let truth (light) in, no lie (darkness/shadow) can remain. Darkness is simply the absence of light, just as your shadow self (persona/character/identity) is just the absence of your true self.
For a lot of us when we think of hell, we don't really imagine fire that never ends or torturing or suffering. For most of us, we go through enough suffering in this life to really be concerned with an eternity of suffering in fiery hell. For most of us, if we really sit and meditate on what hell is to us and really try to imagine hell, it's usually an eternity of being completely alone and isolated in complete darkness of which there would be no light. If you think that's what hell is and you fear that hell, it is because you are already living in darkness. When you live in the light, there is no darkness, it doesn't exist, the fear of the illusion of darkness vanishes.
Maybe you've heard that black dogs and cats are usually last to be adopted. It's no secret that the darker the human skin the less value you have. "the typical White family has eight times the wealth of the typical Black family and five times the wealth of the typical Hispanic family." We avoid what we fear, we fear what we are. We are a species that are living in darkness (lies) and are terrified of the darkness (lies) that we are living in. Peoples skin color has nothing to do with anything but the fear of darkness (our lies). I Love You and Peace Be With You!