4 ms·
One problem with this plan is that mirrors are not perfect and some non-negligible fraction of the incoming light is absorbed and/or scattered away. Even if yo
by randlet 15y ago
One problem with this plan is that mirrors are not perfect and some non-negligible fraction of the incoming light is absorbed and/or scattered away. Even if you could build perfect mirrors, you would still likely need to place the whole setup under vacuum to prevent the light from being scattered by air.
- saraid216 15y agoThe scattering problem is one that confused me, too. At a light-year or several dozen away, there's no way you could find and piece together all the photons that bounced off the moment you're looking for. Am I misunderstanding something?
- thewisedude 15y agoYou are right that regular mirrors absorb or scatter light energy. However, to get 100% reflection it should possible with a setup where the light is getting refracted or bounced off critical angle. http://en.wikipedia.org/wiki/Total_internal_reflection http://en.wikipedia.org/wiki/Total_internal_reflection This is commmonly used in Fibre optics. Its more of an engineering challenge to come up with a setup to view your past than a theoretical one!