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[–]starkeffect 23 points24 points  (6 children)

Black is the absence of light, so no.

[–]WhiteBlackBlueGreen 1 point2 points  (5 children)

its actually more than it seems. Look at this video:

https://youtu.be/p-OCfiglZRQ?si=egGuATYa1Z1vsYbD

You can make light that is perceived as black, which is why you can have a black screen but its turned on and all of the pixels are technically lit. The video sort of explains deeper

[–][deleted] 1 point2 points  (0 children)

Uh... no.

[–]Massive_shit9374 0 points1 point  (0 children)

That way, yes. Black light is possible but it would give close to no light and you would need about three times as much white lights around it to make it seem black in relativity

[–]tyler1128 0 points1 point  (2 children)

What you perceive as black is always in context of other light. Light cannot be black, black is when all wavelengths of visible light are absorbed by something. Now, imagine a projector in a class. Before it is turned on, you probably will see the screen it projects to as white. Once the projector is on, the parts of the screen not illuminated at all look black or at least dark gray. Vision is not objective, it's relative to what you see.

[–][deleted] 0 points1 point  (1 child)

But wouldn't that mean that there is visible and invisible light? If black is when all visible light is absorbed by something? (This is a serious question)

[–]Catillionaire 0 points1 point  (0 children)

Most light is invisible! Visible light is just a tiny fraction of the light spectrum. Invisible light includes radio waves, infrared, ultraviolet, x-ray, and gamma.

[–][deleted] 12 points13 points  (4 children)

Black light is just a marketing term for UV emitting light bulbs. So, no, “black light" is not a real thing.

ETA: Idiot me for not reading the post all the way though. You are asking about a bulb that does not emit light, because that is what the color black is, the non-reflection of any visible light by a pigment. So basically it would be the same as a bulb that was turned off.

EETA: Perhaps a better example is an interior room with no windows and one light bulb. When the bulb is on you see light emitted by the bulb and reflected off the surfaces in the room. When the bulb is off, you see black, not because there is black colored light being emitted from the bulb, but because there is no visible light in the room, which our brains interpret as black.

[–]Earl_your_friend 1 point2 points  (1 child)

I think he wants to walk into his living room in the middle of the day, hit a switch, and have the room become perfectly dark.

[–][deleted] 0 points1 point  (0 children)

He can. He just has to wall up his windows first then hit the switch to “off”.

[–]micemolkok 0 points1 point  (0 children)

What if there is a flashlight that when put on something, magically absorbs all the color from it, making it look black in color. Can that flashlight be call black light?

[–][deleted] 0 points1 point  (0 children)

I have a lot of scorpions on my property so I frequently walk around with some far UV flashlights. When on they don’t appear to emit any visible light but things fluoresce like crazy. The white paint on my walls looks black (like slate walls). That’s about the closest you will get.

[–]Anonymous-USA 13 points14 points  (1 child)

Black light is a common vernacular for UV bulbs and flashlights (which appear purplish/bluish). It’s not actually black “light” from a physics standpoint. Black is the absence of light and the color black (like Vanta Black) simply absorbs reflected light rather than reflects it, so it appears black.

[–]unafraidrabbit 0 points1 point  (0 children)

Adding to this. The reason black lights work is because some objects can absorb UV light and emit it in the visible spectrum. So when something glows under black light, even with other light sources, it is reflecting the UV light and the visible light as visible light, while the other objects only reflect the visible light.

If you saw the NFT festival where people got burns, they were using disinfecting black lights because they just thought they were better. Regular black lights emit UVC in the 290-400 nanometer wavelength while disinfecting black lights emit UVA in the 100-290 nm wavelength, which is harmful to biological material.

[–]xyzzzzy 7 points8 points  (3 children)

Y'all are disappointing me today. The obvious answer is to create a Kugelblitz bulb. Basically a small black hole. Turn that on and you could definitely make some darkness. Disclaimers: 1) for a 1kg Kugelblitz bulb the event horizon would be very small (nanometers), so not much darkness, 2) to power it you would need to convert the entire energy output of the Sun over about 45 seconds into a space less than a nanometer across, 3) unless you have a way to stabilize it it would rapidly evaporate with the yield of about a 20 kiloton nuke

..."so you're saying it's possible!"

[–]1Z2O3R4O5A6R7K8 1 point2 points  (1 child)

Wait 20 kilotons worth of hawking radiation? From a kugelblitz? I thought that stuff was weak

[–]Tarnarmour 0 points1 point  (0 children)

It gets stronger as the black hole gets smaller, because the radiation emitted has a wavelength on the order of the diameter of the black hole. Large black hole means long wavelength, low energy light. Small black hole means short wavelength high energy light.

[–]Griffith9011 0 points1 point  (0 children)

Hey, that's the umbrella academy word (he says high off his head)

[–]MuForceShoelace 4 points5 points  (1 child)

Not in any real way. But to a human, a movie projector can project black, even when projected onto a white screen. Because human visual stuff is all relative and we can accept the darkest area as black, even if we can see it's unlit white.

[–]DJOMaul 0 points1 point  (0 children)

fuspez

[–]Radiant_Grocery_1583 1 point2 points  (1 child)

Your question was answered below however, your thinking about light shows a healthy level of curiosity. The subject is fascinating and there are a plethora of resources out there to help you learn. Light bulbs do not create "sparks of incandescence", they emit photons of light which are packets of energy created when electrons jump from one energy level to the next at different wavelengths. Our eyes are tuned to see only a few of those wavelengths but the spectrum of light is quite broad. Try "Minute Physics" on YouTube to start. Stay curious!

[–]Moving-Forward9276 1 point2 points  (0 children)

I would think this could be done through trickery. I imagine a pair of glasses or goggles that when hit with a wavelength of light, they polarize to black. This would have the effect of turning on a “light” and creating darkness. I would have no idea how to build such a thing but I’m fairly certain it’s possible.

[–]Phoenix4264 1 point2 points  (0 children)

Generally speaking, no you can't make a light that projects darkness.

The exception to this is if you have a light that will destructively interfere with the existing light. When the two waves add together they cancel each other, leaving you with no light. This isn't a practical option that will allow you to make a flashlight that creates a black spot, but it can be demonstrated.

[–]Excellent_Speech_901 2 points3 points  (5 children)

Yes, I have made this black light. As you see, or no longer see, now that I have turned it on all the light in the room ceases. And when I connect you to it, Generator Man, all light will drained from the world. Muhahaha. Someday I will have the stars!

If the above qualifies as real life then yes. Otherwise, see all the other replies.

[–]Half-Borg 1 point2 points  (3 children)

It's this the real life? Is it just fantasy?

[–][deleted] 0 points1 point  (2 children)

Easy come, easy go. Just send a bolt of lightning…

[–]entitysix 0 points1 point  (1 child)

Black lightning

[–][deleted] 0 points1 point  (0 children)

Bohemian Rhapsody man. Come on. Lol

[–]Bacardi-1974 0 points1 point  (0 children)

There are differences when speaking of the color black which is all the colors mixed like craft-painting in school or home and black as a term for our ignorance, the absence of light.

[–]Funny_Anxiety_9058 0 points1 point  (0 children)

It's lightwaves, the reflection of lightwaves off objects

[–]Afraid_Performer5183 0 points1 point  (0 children)

Not that I did that well in physics 101, but to my understanding, white light is a combination of all the wavelengths of color, and black light has wavelengths combinations. It is a total whack of light waves. That's the term black light doesn't mean it's black, that means it's just hard to see is different. Like physics is a very interesting thing, like optical calcite. And then you get optical calcite that is fluorescent and you've got lots of fun!

[–]Financial-Estimate82 0 points1 point  (0 children)

WAIT I FIGURED IT OUT. BLACK LIGHT IS SHADOWS!! So for a room optimally lit with this type of "black light" would just be a dimly lit room.

[–]Blakut 0 points1 point  (0 children)

i can think of only one way to achieve this:
if the human eye was built in such a way that, when hit by light of a certain wavelength, the rod/cone cells in our eyes stopped working and simply shut down somehow (temporarily). That would look in a way, i suppose, like dark/black light.

[–]Coinless_Clerk00 -4 points-3 points  (1 child)

Decolonialize physics! Black light for diversity!

[–][deleted] 0 points1 point  (0 children)

To be clear… no. Physics does not allow this. White is every color emitted or reflected back into your eyeballs. That is why prisms work the way they do. When you see black, the material is absorbing all the color frequencies and bouncing nothing back into your eyeballs, so it appears black. So if any colored light frequencies bounced back into your eye, you’d see the colors that did not get absorbed. Hence a red shirt absorbs every color of light except the red wavelength which gets bounced back into your eyeball. There’s no such thing as light which is black. It’s impossible.

[–]Former-Chocolate-793 0 points1 point  (0 children)

Black light is common vernacular for uv lights.

[–]MsPaganPoetry 0 points1 point  (0 children)

No. What we call black is just a thing absorbing all the light. Bulbs can't glow black.

[–]BlightPaladin 0 points1 point  (0 children)

Black as a colour in paint is basically all colour pigments mixed together. You cannot find "black" as a part of the visible spectrum of colours available to us humans and you won't get it out of a prism.

You also couldn't really create a "beam" of dark like a flashlight, which is what it sounds like you're asking. You might be able to create some shade by obscuring a light source, but I'm afraid black light, in the form you're describing it, does not exist.

[–]darlingsghoul 0 points1 point  (0 children)

“Black light” is just a marketing term used to describe lights that are really more blue/purple. Since black is the absence of light, it’s impossible for there to be black light. The term “black light”, if true, would be saying “no light light”, which is obviously not possible.

[–]WhiteBlackBlueGreen 0 points1 point  (0 children)

All of these commenters have never seen the action lab video about this. Tldw: we can make light that is perceived as black. I assume you are reading this with dark mode enabled.

If you surround a white light with an even brighter white backlight, you perceive the middle light as black, even though its white.

https://youtu.be/p-OCfiglZRQ?si=egGuATYa1Z1vsYbD

[–]Cosmiccoffeegrinder 0 points1 point  (0 children)

Fuck yeah black light is a thing, my room was full of them. I had all these bad ass poster's that would react to the black lights, then I would get super stoned and get lost listening to Black Sabbath.

[–]selfdestructivenerd 0 points1 point  (0 children)

Hmm, interesting question once you get past the pretext of "common knowledge". What about destructive interference? Photons are waves and particles simultaneously so Im not even sure the principle could apply; However I'm not seeing any attempt at an experiment like that through online searches.

[–]Kinis_Deren 0 points1 point  (0 children)

Purely hypothetical, but dark photons have been suggested as a force carrier in extensions of the standard model. In some respects, dark photons would meet your criteria as a form of "black light" since we'd not be able to observe them directly.

[–]adamdoesmusic 0 points1 point  (0 children)

Get Anish Kapoor to paint a bulb for you. He’s the only one allowed to do it if it’s for an art piece.

[–][deleted] 0 points1 point  (0 children)

Yeah it’s called any object in the universe between zero Kelvin and the temperature at which it starts to glow red.

[–]ZedZero12345 0 points1 point  (0 children)

It's a slang term for the UV light spectrum. It goes from violet to beyond violet in the light spectrum. But it collectively know as Black Light. Remember the spectrum with Roy G. Biv (Red, Orange, Yellow, Green, Blue, Indigo, and Violet)

[–]GlaiveGary 0 points1 point  (0 children)

This isn't an astrophysics question, but...

Can you create a shadow out of thin air, with nothing around it?

So you're not asking about a light, you're asking about a shadow emitter? Something that destroys light? Am i getting that right? No, you cannot create "anti light" like that, that's not a thing.

[–]of_thewoods 0 points1 point  (0 children)

Hue and pigment are different.

When full Red Blue and Green hues are mixed at full they generate white light. Anytime the bulbs are illuminated to produce any color they are emitting light. I think of lighting in musical terms. The only time there is “darkness/black out” in music is in the rests. Real shadow, black/dark, is inherently a space void of light or lacking in light at least compared to lights around it. So if the lights are on, and with in our field of perception, it’ll never be black. I often use the illusion of light and shadow thru the use of warm and cool colors though bc our brains need shadows or they dk wtf is going on. This is fun tho bc I can manipulate that “shadow” and have some control over the audience sensory perception. This is especially fun at hippie shows where folks are even more sensitive from the party favors they have taken.

Source: Am a lighting designer

[–]davehoug 0 points1 point  (0 children)

For a WEIRD thing, 'there is no such thing as brown light' :)

Brown is dim orange surrounded by something brighter. Can not create a brown spotlight.

https://www.youtube.com/watch?v=wh4aWZRtTwU&pp=ygUFYnJvd24%3D

[–][deleted] 0 points1 point  (0 children)

All matter produces light. We can only see a small sliver of that light spectrum called visible light. If you want to call that "black light," then so be it. I think some animals can see "black light," but that's a question for a biologist.

[–][deleted] 0 points1 point  (0 children)

Not what you're looking for, but dark photons have been theorized.