Hello, my name is Edward Solomon, after much experimentation and calculation I have failed to make a system that can reflect light in a closed system. Now I am not naive enough to believe I can make a true closed system. There is an absorption and conversion to heat each time light strikes a mirror. Also, as my mirrors are not smoothest mirrors available, not all of the light is reflecting exactly where it should be. My actual goal was to create a system that could concentrate a high density of light by having it reflect in a circular pattern. Let our Light Source be Z, let mirror one be A, let mirror two be B and let mirror 3 be C. My goal is for the light to travel as follows. Z to A to B to C to A to B to C to A. . . with the light striking the same spot of its respective mirror that it had hit before. You would get something that appears like this. Z-----A xxxxxx/\ xxxxx / \ xxxxC---B This would cause a concentration of light whose luminosity that would be equal to L times the original luminosity, where L = limit of the series (A/B)^n where is A/B is the statistical mean percentage of the light reflected when absorption and mirror roughness are factored in. The most obvious problem that arose was that the light source itself, Z, obstructs the light. Thus this system only seems to be achievable if the light source itself is a mirror (and in that case we would only need two mirrors). So Z to A to Z to A to Z to A to Z to A. . . Z---A Let us assume that between the absorption and the imperfect surface of the mirror that we get a statistical mean of 90% reflection of the incoming light per reflection. Thus after one reflection (assuming the light source remains on the entire time) we would have 190% of our original luminosity. After the second reflection (of the source mirror) we would have 271% of the original luminosity. As the series of (9/10)^n converges on 9, after exactly 65 reflections we would have 999.04% of our original luminosity, or nearly ten times as much luminosity of the original light source. Of course this experiment is fictional and not at all possible as the source cannot be a reflective surface, as far as I know. So my question is: Is it possible by using a set mirrors of different shapes (planar/parabolic/hyperbolic/etc) to create a closed system, one that can avoid including the light source to the first mirror, Z to A, in the path of a closed system.