IANA physicist, but I thought I would run my musings on this OP past the teeming masses.
We have a spherical chamber. This chamber is constructed from a material that has two special physical properties:
A) the inside of the chamber reflects light perfectly
B) the outside of the chamber is transparent to light
So it is built out of the stuff they use to make mirror sunglasses. The *really * expensive stuff.
We can postulate that the concentration of light photons inside the chamber will increase with time. From this we can make two inferences:
- Individual photons have momentum. Photons reflecting off the inside of the chamber will exert pressure. That pressure will increase with time.
- A system of photons has mass. The mass of the chamber will increase with time.
So, if you wait long enough, this is what I think will happen to your light battery:
i) The pressure acting on the inside of the sphere will increase until such time it explodes. At this point be careful to look away.
Now if we add a third attribute to the physical properties of our light battery, we can overcome this problem:
C) the chamber is very, very strong
In this case, I think a different destiny might await our battery:
ii) The mass of the sphere will increase until such time it becomes a black hole. At this point be careful not to stand too close.
A bit of a WAG really, we need a physicist’s view!