electromagnetic radiation - What's it like in a sphere mirror?

Possible Duplicate:
What happens to light in a perfect reflective sphere?

I was working on my toy ray tracer when I pondered on this:

Say we build a hollow sphere big enough to fit a person. The internal surface is perfect mirror, with no cracks or holes. We place an invisible observer with an invisible flashlight, just for the sake of argument, inside the sphere. The flashlight is turned on for, say, 1 second. What does the observer continue to see after the flashlight has been turned off, and why?

1. it is pitch black, so he can't see anything.


2. there is just as much light as when the flashlight was on, but it dims and eventually becomes pitch black?


3. it isn't pitch black, and he can see.