Focusing light with a light sail

[beek]

<Moderator's note: post split off from another thread>

OK I'm new here i have read all the questions and comments. the whole reason i did is because of light energy.
"More photons packed in a smaller area = higher light intensity in that area".
and solar sails work?
so why can't scientists make a solar sail (giving them forward movement) reflect that light to a single spot giving them more "intensity" to produce more energy for more forward movement.
wouldn't that give them the energy they need to reach into space farther and faster?

 

[jbriggs444]

<Moderator's note: post split off from another thread>

OK I'm new here i have read all the questions and comments. the whole reason i did is because of light energy.
"More photons packed in a smaller area = higher light intensity in that area".
and solar sails work?
so why can't scientists make a solar sail (giving them forward movement) reflect that light to a single spot giving them more "intensity" to produce more energy for more forward movement.
wouldn't that give them the energy they need to reach into space farther and faster?

Higher intensity in smaller area. Same total force. Same total power. You can't get something for nothing.

Edit: Plus, if you've reflected the light backward, harvesting forward momentum for your craft, anything you do to that light at the focal region will harvest backward momentum. That's the opposite of what you need.