Can Light Be Stored?

The title says it all, can light be stored, like in a container of some sort?

Also, how much light can you cram into a container?

Not really. That’s an easy to repeat experiment at home. Shine a light into a container and try to seal it in.


Yeah, the answer is “not really.” It can be contained, but that diminishes over time. If nothing else, each time a photon, a “piece of light” interacts with the electrons in the container wall, it’s going to transfer some of its momentum/energy to those electrons, thereby diminishing its frequency (energy). Then there are scattering effects and…yeah, it gets really complicated. It’s why you can’t make a fiber-optic cable of infinite length: there’s always loss to the environment.


Light is both particle (photon) and electromagnetic wave . It gets absorbed by the medium it encounters . An electron from an atom/molecule captures it , goes into a higher energy state , then it goes back to energy state prior to capturing the photon , by releasing back another photon . It’s how we have colors, substances absorb and emit light at different wavelengths.
Ultimately it is nothing but energy , so yes it is stored in a way . When you burn gasoline for example you get the flames , that comes from oxidizing the octane/iso-octane . The molecular bonds break and emit energy under the form of light and heat . The electrons get into higher states of energy by occupying high energy state orbitals/anti-orbitals , but those states are unstable mostly , so they go back to prior low energy states by emitting light(photons) back and forming much stable molecules like CO2 for example and water (a more stable thermodynamic system). Same thing you can say about enriched uranium or plutonium , when it goes critical you create an artificial “sun” , except that there the process is entirely physical and not chemical. So you can say that it has “stored light” , because ultimately light is just a form of energy. To give you another example, see tritium lamps.
Another one that I can think of would be photosynthesis , where light is converted into chemical energy in plants under the form of molecules like glucose and cellulose . If you burn a leaf for example , you break the bonds of those molecules and release heat and light back along side CO2 and water + carbon as ash .

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Light has been stopped! So technically you could say it was contained!


How much light is trapped inside black holes ? Who can say ?!

There are only 2 types of light that can be stored in a can.

Bud and Coors.


Of course! You need construct a gravitational field in such a way to loop the spacetime upon itself where light beam would travel in a closed circle indefinitely. Such fields occur naturally near the event horizon of a black hole.
For further reference see here
As to how much light you can pack there is simple enough to calculate: light, being energy can translate to radiant mass, which then can be used in Schwarzschild solituion to Einstein field equations to determine how much energy (light) you can pack into said volume without it turning into a black hole itself. But that would require complex mathematics which i’m too lazy to do here.


Keystone, busch, miller etc :joy:

Which is why at a point if you pack enough of it it can create a space-time rupture into our know universe , a singularity point … well at least in theory , the mathematical model is there , but the tech is “out of this universe” .

Light can be stored, and is stored all the time on a large scale. It’s part of the process of photosynthesis.

Tree takes in light and, along with water and other things, makes the products it makes including its own mass.

Later, you burn that mass in a fireplace or something else and the light is released in the form of fire.


I can think of some constructions that could hold la photon of ight: for example a photon orbiting on the event horizon of a singularity - I didn’t say easy or stable.

A wave in a circular perfect waveguide would do it, but any losses with attenuate it quite rapidly below detectable levels.

If I was asked to catch a photon and release an identical photon on demand I’d make a use a lasing chamber - you get an identical output to the input. But that’s more analogous to recording a sound by shouting the same thing every time you hear the echo.

Theres a whole philosophical line here around "what does storing a waveform mean? Is a perfect replica the same as the original? Can you determine the difference between two photons? If you can’t then are they different?

Of course if the question is just “can light be stored?” Then a box with a photoelectric panel on it, a battery and a LED takes light in and releases light on demand. With losses of course, but that’s thermodynamics for you.
That’s good enough for “storing daylight so I can use it to read after sunset” type light storing. And sometimes that what you are wanting.

I am afraid you are not correct on your opinion as Photosynthesis is the biological process to convert light into chemical energy. It does not store light then release it!

But if you have a sealed container with a light inside how do you know the light is gone if you don’t look and if you do look the light escapes? :wink:

Anyway, the reason I asked is we were discussing the idea of storing light and then converting it to electricity as needed.

A “Light Battery”. :bulb:

That would not be storing and releasing light on demand as the original light is converted into energy ie: electricity and that energy released into a light producing object!

More reflective wall? I am not a physicist :slight_smile:

The conversion process of electromagnetic energy under the form of light into chemical energy (which ultimately is also electromagnetic energy) in plants is a biochemical one . Yes, it does happen into a biological organism , but it’s not biological , you can say that mitosis for example is a biological process , but light conversion is biochemical there, it’s stored under the form of sugars like glucose and cellulose.
That energy you can then release it by burning fire wood for example (oxidizing said sugars) under the form of light and heat .

There’s also situations when the electron is “happy and stable” in the new higher energy state.

Light or visible light is electromagnetic radiation converted into chemical energy! This chemical energy is stored in carbohydrate molecules within plants not electromagnetic energy as you are mistakingly thinking!

A more reflective wall certainly helps, as that reduces scattering losses. Unfortunately, even a perfectly mirrored wall is still going to have electrons in it that the photons interact with and lose energy to. After a certain number of interactions, any single photon is going to lose all of its energy. Now, how many interactions that takes depends on the temperature of the container wall, the frequency of the light, the bond lengths of the molecules making up the wall, the lengths of the crystalline structure,…I mean this isn’t my field of specialty, I’m just a poor astronomer, but I can say that, yes, we can make some pretty good containers now, but like the containers for just about anything, they’re not perfect and certainly won’t work forever. Relatively speaking light containers are short-lived because the speed of light, hence the number of interactions per second, is so blessed high. :smiley:

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