"Teacherjh" wrote in message
...

So why can't we use high-intensity lights powered by a nuclear reactor
as a source of space propulsion?


They can. But the F is small, so you need a lot of t to reach much of a
v, as
long as you are far enough from a g.

Such systems have only been developed in science fiction however because
we are
not yet doing enough interstellar travel, and people are uncomfortable
with
nuclear reactors in space.

Here is something interesting Jose.

Although light is not conducted like RF, light behaves very much like RF in
a wave guide.