Originally posted by mlprior
Yes, smarty pants....it's a mirror.
OK, I'm not talking about reflecting light, I'm talking about absorbing and then trapping it.
Oh, never mind already!
There are mirror arrays that can trap light but there is no reflecting surface, no matter what kind that is 100% reflective, even the multilayer additive reflection coatings are say 99.9% reflective. So that means that after 1000 such reflection, there will be no more light left but you can trap light for that time/distance, say a series of mirrors to slightly deflect a beam eventually bringing it around to the original mirror, which would have a hole in it for the entering beam but enough area around it to keep the beam going in a daisy chain kind of thing, so if one trip around took (picking a # out of mid air) say, 20 mirrors are arranged to reflect a beam around a circumferance of 10 meters, say, well light goes about 300 million meters per second so one meter takes light about 3 nanoseconds in space, a bit slower in air and a lot slower in water but you get the idea, so in our example, 99.9% reflective mirrors, 20 of them sending light on a series of reflections that ends up being a total of ten meters would lose 20/1000ths of its energy on each trip around the circle (2 percent) So it would lose all of its energy after 50 circular trips, supposing you had a VERY fast way to switch on and off the light beam, so you make a light beam that is 10 meters long, or about 30 nanoseconds of light and let that into the mirror system, the leading edge of the beam would go round the circle just in time to see the tail end of the beam and you would get 50 such trips or a trail of light that would follow its tail so to speak, for about 1500 nanoseconds or 1.5 microseconds for a total beam path of about 1500 meters before it poops out. Now if the beam was very well collimated, say a nice tight laser beam, and the mirrors were in space with no air you could separate the mirrors to give say, 1000 meters circular light path and the beam would last 100 times longer or 150 microseconds, still not a whole lot of time! It takes 1000 microseconds to equal one millisecond so you can see that would be about 0.15 milliseconds, the light would still be dead before you can blink. So the storage part won't fly. Absorbing on the other hand, there are carbon nanotube absorbers now that absorb something like 99.9999% of light hitting such a surface, the blackest black of all times but it would in turn heat up the surface, turn it into infrared energy and re-emit it as heat radiation as well. So the trapping part can be done but what do you do with it after that? Now its heat. Be a great solar heating collector, it absorbs light better than anything else ever. Outside of that application though, not sure what you would do with it. I guess you could use it for those black velvet Elvis paintings you get in Tijuana🙂