Re: Gas Core Nuclear SSTO...
A lot of smart people have looked at gas core reactors, and the idea is not as dumb as it looks. The "light bulb" concept does have cooling issues, but no more than the metal walls of a rocket engine containing materials at a temperature high above the melting point of those metals. The trick is dumping the heat into the propellant, not the walls. Getting a propellant that absorbs the light frequencies to heat the propellant the right way is also tricky.