that highdea ^
you're in a room where the floor, ceiling, and walls are all mirrors and then you have a tiny hole at the top for a light to shine into the room. when you turn the light on, it shines from one mirror to the next but since the mirror is replicating the light bulb with the light, when you turned the light off, would the room still be lit? better yet, would the room be getting brighter and brighter because of the light being added to the room from the lightbulb?

Made popular on: 
Mon, 01/02/2012 - 9:21pm


Wed, 08/24/2011 - 11:09pm
Gizmodo Says:

sorry if this is already a highdea, i cant remember if i thought of this before, or if i read this before

Mon, 01/02/2012 - 1:42pm
Ctodenbach Says:

This is the technology they use for street lights!

If you turned the light off, will there be light? No. Not a chance man. That would be pretty rad if there was though. I'd make my whole house like this cuz I'm scared of the dark.

Mon, 01/02/2012 - 2:00pm
Gizmodo Says:

yeah the light energy would just turn into other forms of energy, mostly heat

Tue, 01/03/2012 - 3:58am
bucketgirl Says:

So actually those light "particles" would disperse, but not all of them would end up in our particular universe, and we'd get some leftovers from others where people much like us had got high and had a moment with mirrors, however the previous guy is right that eventually the energy would disperse, in This universe according to it's laws (which, interestingly, hitchiker photons ignore.)

Mon, 01/02/2012 - 10:25pm

You'd have to turn it on and off at the speed of light.

Sun, 09/18/2011 - 12:35am

dude, that's my highdea! wow!

I figure with enough reflection, maybe not in a simple case like six mirrors (4 walls and a ceiling), but in a more extended set of reflections over a larger space, your predictions would be measurably correct!

Sun, 09/18/2011 - 5:51pm
Gizmodo Says:

i think the light would go out tho because it would turn into heat energy

Fri, 10/07/2011 - 11:32am

K your going to have to bear with me on this one. What if the lightbulb itself was like one of those mirrors where you can see through but on the other side it a mirror. Then the light could get through to the room but not back out. And if the mirrors reflect 100 percent of the light then i dont think it would turn off, it just keeps getting reflected back to another mirror. But im pretty sure mirrors cant reflect 100 percent and since the light is bouncing back and forth thousands of times a second (just a guess) then it would loses energy pretty fast if you think about it. So i agree with gizmodo, that it would probably end up turning into heat. Thanks once again for thoroughly blowing my mind.

Tue, 01/03/2012 - 2:05am

Those things don't actually work that way. Instead, a 1 way mirror has a reflective coating on one side but not completely covering it, as if it was sprayed on really finely so it only reflects a portion of the light. Then the non-reflective side is kept dark and the reflective side is kept well lit so the lit side has a strong reflection back creating a mirror illusion (the reflected light will be much stronger than the extremely dim light coming from the non-reflective side) while the dark side sees the portion of the light that isn't reflected. If you light both sides equally, it is essentially a window.

Tue, 01/03/2012 - 4:02am
bucketgirl Says:

There is no purely reflective surface (if there was I'd probably just wanna put it in my mouth) it all has minor imperfections that would eventually dissipate the energy. If we had something that didn't maybe it wouldn't be such a warm winter... It'd be ideal energy.

Mon, 01/02/2012 - 3:40pm

interesting theory but ofc it wouldnt work as you guys have figured out
i wonder what would happen if you shot a super-powerful laser out into space, waited a year so it reached a lightyear, and turned it off
would the entire beam dissipate immediately?
it's unlikely that the light would simply dissipate as soon as the source was turned off
surely if you only held the laser on for a second or two, the original burst of light wouldn't travel the full light year, so how long would the beam last once turned off? how far would the last remnants of light shot from the laser reach?

Mon, 01/02/2012 - 5:21pm

This should have been it's own highdea. Very interesting. Let's do it!

Tue, 01/03/2012 - 12:21am
Gizmodo Says:

it depends what kind of laser. if its a laser that creates a trail...then it would travel until it all turned to heat energy too, but it would take longer.

if its a laser like the laser pointers, they only show when they hit a surface, so they would go out immediately

Tue, 01/03/2012 - 1:38am

by "laser that creates a trail' you mean powerful lasers that you can see the entire beam of?
with weak laser pointers, just because you can't see the trail doesn't mean it's not there :o
the only difference is the power (megawatts) of the laser, the higher the power, the higher the 'lumens' or brightness
i think i agree though, once the source of energy shuts off, the light will simply dissipate into heat energy rather rapidly i imagine
but would it do so from rear to front, or all at once?

Tue, 01/03/2012 - 1:56am

When you turn it on, you are shooting a bunch of protons out in a tight cluster. If you shoot it into space for a second and then turn it off, there is a second of light traveling until it hits something or disperses.
The reason it seems instantaneous is because at the distances we are used to, it happens very quickly.
Here's an example; Look at the stars. The light from those stars come from millions of light years away. That means that the light you are seeing was emitted millions of years ago. In the intervening years since that light left that star and traveled here, that star may well have been destroyed or changed positions, but we see the image of it from the past, regardless of whether or not the source still exists.

Let's assume you have an observer 1 lightyear away looking at the precise spot you are shooting from. Then if you shoot an extremely powerful laser into space for 1 second, assuming it doesn't disperse to the point where it's undetectable first, then one year later, your observer would see a laser light for 1 second before it turns off.

Tue, 01/03/2012 - 5:58am

very good reasoning, that is quite possible
but idk for sure, i think there's a massive leap between lasers and stars dude
a star is exponentially brighter than any laser, not to mention, if the star does go out, it would probably have supernova'd and become massively brighter, so of course the light would continue to reach us for a long time after it has died
also i think ur oversimplifying what light is, light isn't simply a bunch of protons, and the medium in which light propagates is even questionable
i need stephen hawking to explain the answer to me on a quantum mechanical level :/

Tue, 01/03/2012 - 1:20pm

Whoops. I meant to say "photons" instead of "protons". It's amazing how much a stoned typo can change the correctness of a statement.

Sat, 01/07/2012 - 8:03pm
Mon, 01/02/2012 - 9:38pm
ganjgrl420 Says:

This is too complicated and long to understand i forgot what the point of the story was

Mon, 01/02/2012 - 10:06pm

THAT was too long???? Jesus christ it's like 6 lines smh. It'll make sense if you put your eye real real close to your computer and just leave it there for at least an hour or two

Mon, 01/02/2012 - 10:36pm

i did that! look what my eye turned out to be!

Mon, 01/02/2012 - 9:57pm

I've always wondered somethin like that also I wanna kno if you have a square room with mirrors covering the whole room then what would the mirrors look like?

Tue, 01/03/2012 - 6:00am

the mirrors would look like a mirror inside of a mirror inside of a mirror getting infinitely smaller (if there were one mirror on each side of the square room)
if there were multiple mirrors on each side... i think it would be the same thing if each wall had the same size and number of mirrors

Mon, 01/02/2012 - 10:35pm

light of course moves at the speed of light. the fastest speed recorded. faster than the naked eye can see. what would happen is all that light would escape threw that single spot where light comes in. it would escape at the sped of light therefore it would seem to disappear instantly

Tue, 01/03/2012 - 6:01am

yea im not wondering what the cognitive experience would observe
i wonder what would happen on a scientific level

Mon, 01/02/2012 - 11:19pm

according to Indiana jones and the temple of doom and the Mummy yes.

Tue, 01/03/2012 - 2:00am

To be honest, I think this is perfectly possible under extremely ideal conditions. You would need a perfectly reflective and elastic surface so your photons never lose energy. You need to have absolutely no seams so no photon can hit the seam and escape. You need to make sure nothing on the interior can absorb energy. You need to have a way to put light into the container in such a way that it traps it.
If you put the light source, complete with power supply into it (To get rid of seams), guess what? Light can hit your light source and power supply and dissipate.

While nothing in physics TECHNICALLY prevents the photon trap from working, in all practically it is impossible.

Tue, 01/03/2012 - 6:03am

hmm interesting idea, inside of a vacuum light would dissipate much less, but there is no way to make a mirror that wouldn't absorb some energy
maybe if the walls were made of anti-matter... ahah!
if light bounced around in an endless cycle within an anti-gravity vacuum, well we would have a limitless light source..
id rather use a solar powered flashlight though :P

Wed, 01/04/2012 - 6:42am
Highwalker Says: