Can you solve this physics 'thought experiment' involving light and 2-way mirrors?

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Given: Imagine a fist-sized cube made of high quality 2-way mirrors where all reflective surfaces are on the inside (so that light passes easily into the cube).

Question: If a bright external light source is focused on a wall of the cube and maintained indefinitely, what happens to the photon density inside the cube? Would it keep increasing without limit?

My thoughts: The cube is a 'leaky' light trap. Imagine just a single photon passes into the cube. That photon has a certain probability of passing out of the cube every time it meets one of the internal reflective mirror surfaces, but a HIGHER probability of reflecting and remaining in the cube a while longer. Now, for a constant external light source, billions of photons are coming into the cube much faster than the internal photons can leak out, leading to a net increase of photon density. If this is true, something has got to give! Photon density surely can't increase towards infinity?
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I believe you are right in the sense that it is leaky. Knowing that, it can increase towards infinity however never actually give and more and more photons will just leak out. There is a probability that each individual photon will leak out eventually.

I believe that they will bounce around and collide with each other so that heat will be generated but also increasing the chances that they escape because they travel at higher velocities. Depending on the quality, it will only give way to heat and or density.

Of course, since this is an imganiary cube, in theory, it could also get infinitely hot or melt the 2-way mirrors.

If it could be done, that would be a real big explosion.

Thats interesting stuff though :)
 
Good question. Simple answer: in physics there is no limit how high the density of photons can be. Photons are considered to have zero dimensions - to be infinitely small. You could have an infinite amount of energy in a single point. in fact, that is the basis for our idea of the big bang starting as a point: that everything in the universe emerged from a single point.

Astonishing, eh?
 
Good question. Simple answer: in physics there is no limit how high the density of photons can be. Photons are considered to have zero dimensions - to be infinitely small. You could have an infinite amount of energy in a single point. in fact, that is the basis for our idea of the big bang starting as a point: that everything in the universe emerged from a single point.

Astonishing, eh?
 
Good question. Simple answer: in physics there is no limit how high the density of photons can be. Photons are considered to have zero dimensions - to be infinitely small. You could have an infinite amount of energy in a single point. in fact, that is the basis for our idea of the big bang starting as a point: that everything in the universe emerged from a single point.

Astonishing, eh?
 
Good question. Simple answer: in physics there is no limit how high the density of photons can be. Photons are considered to have zero dimensions - to be infinitely small. You could have an infinite amount of energy in a single point. in fact, that is the basis for our idea of the big bang starting as a point: that everything in the universe emerged from a single point.

Astonishing, eh?
 
Good question. Simple answer: in physics there is no limit how high the density of photons can be. Photons are considered to have zero dimensions - to be infinitely small. You could have an infinite amount of energy in a single point. in fact, that is the basis for our idea of the big bang starting as a point: that everything in the universe emerged from a single point.

Astonishing, eh?
 
Good question. Simple answer: in physics there is no limit how high the density of photons can be. Photons are considered to have zero dimensions - to be infinitely small. You could have an infinite amount of energy in a single point. in fact, that is the basis for our idea of the big bang starting as a point: that everything in the universe emerged from a single point.

Astonishing, eh?
 
Good question. Simple answer: in physics there is no limit how high the density of photons can be. Photons are considered to have zero dimensions - to be infinitely small. You could have an infinite amount of energy in a single point. in fact, that is the basis for our idea of the big bang starting as a point: that everything in the universe emerged from a single point.

Astonishing, eh?
 
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